USMLE : ICM And Pathology Questions! Trivia Quiz

1. A 53-year-old caucasian male comes in with a 2-week history of severe headaches mostly occurring during the night. The patient is pacing while he is talking. During the history taking, he states that the symptoms of pain surround 1 eye and last for 30 to 90 minutes in duration. He also states that there is ipsilateral lacrimation, conjunctival injection, and nasal congestion during the attacks. The patient states that he's had these headaches 2 or more times in a day over a period of several weeks. He cannot point to any one thing that causes them. On examination, the patient has features of partial Horner's syndrome. His vital signs are temperature: 97.0 °F, heart rate: 80/mir, respiration: 16/min, and blood pressure: 126/80mmHg. Question: The client's headache is a:

Common migraine

Classic migraine

Cluster Headache

Stress headache

Chronic daily Headache

Cluster headaches come in groups and may be separated by months or years between attacks. There are 2 types: episodic and chronic. The patient is often a middle-aged man. Cluster headaches are characterized by unilateral excruciating pain (stabbing sensation) often occurring in the ocular, frontal, or temporal areas. These headaches generally last for a period of 15 minutes to 3 hours, recurring at the same time of day. They typically occur during the night. Pain often radiates to the upper teeth, jaw, and neck. The pain is normally accompanied by one or more of the following: ipsilateral conjunctival injection or lacrinnation, ipsilateral nasal congestion or rhinorrhea, ipsilateral eyelid edema, ipsilateral forehead and facial sweating, ipsilateral miosis or ptosis, and a sense of restlessness or agitation. Restlessness is one of the characteristic features of cluster headaches noted in patients. with behaviors such as pacing or rocking the head and trunk with head in hands. Other symptoms of cluster headache include facial flushing or pallor, tenderness on palpation of the ipsilateral carotid artery, bradycardia, and tenderness of the scalp and facial areas. The absence of aura, nausea, or vomiting helps in distinguishing cluster headaches from migraines.
The treatment of choice for acute cluster headaches include the administration of oxygen (7 L per minute for 15 minutes) or sumatriptan, or a combination of both. Other therapeutic measures include intranasal dihydroergotamine, intranasal capsaicin, or intranasal lidocaine. Prednisone and verapamil are often used in prophylaxis.
COMMON MIGRAINE is an intermittent syndrome characterized by hemi-cranial pulsatile cephalic discomfort, including nausea, vomiting, photophobia, anorexia, and phonophobia.
CLASSIC MIGRAINE typically presents with an aura. It also includes features of nausea, vomiting, photophobia, anorexia, phonophobia, and a sense of just wanting to hide in a quiet dark room.
Stress/tension headaches are a generalized type of headache precipitated by stress. They are not one sided. They do not involve photophobia, nausea, vomiting, aura, or phonophobia.
CHRONIC DAILY HEADACHES occur on a daily basis and are often disabling. This type of headache may be challenging to diagnose and treat. Medication overuse, or drug rebound headache, is the most treatable form of refractory daily headache.
A 10-year-old female presents with severe headache and ataxia. Neuroracliologic imaging reveals a cystic tumor in

Explanation

Cluster headaches come in groups and may be separated by months or years between attacks. There are 2 types: episodic and chronic. The patient is often a middle-aged man. Cluster headaches are characterized by unilateral excruciating pain (stabbing sensation) often occurring in the ocular, frontal, or temporal areas. These headaches generally last for a period of 15 minutes to 3 hours, recurring at the same time of day. They typically occur during the night. Pain often radiates to the upper teeth, jaw, and neck. The pain is normally accompanied by one or more of the following: ipsilateral conjunctival injection or lacrinnation, ipsilateral nasal congestion or rhinorrhea, ipsilateral eyelid edema, ipsilateral forehead and facial sweating, ipsilateral miosis or ptosis, and a sense of restlessness or agitation. Restlessness is one of the characteristic features of cluster headaches noted in patients. with behaviors such as pacing or rocking the head and trunk with head in hands. Other symptoms of cluster headache include facial flushing or pallor, tenderness on palpation of the ipsilateral carotid artery, bradycardia, and tenderness of the scalp and facial areas. The absence of aura, nausea, or vomiting helps in distinguishing cluster headaches from migraines.
The treatment of choice for acute cluster headaches include the administration of oxygen (7 L per minute for 15 minutes) or sumatriptan, or a combination of both. Other therapeutic measures include intranasal dihydroergotamine, intranasal capsaicin, or intranasal lidocaine. Prednisone and verapamil are often used in prophylaxis.
COMMON MIGRAINE is an intermittent syndrome characterized by hemi-cranial pulsatile cephalic discomfort, including nausea, vomiting, photophobia, anorexia, and phonophobia.
CLASSIC MIGRAINE typically presents with an aura. It also includes features of nausea, vomiting, photophobia, anorexia, phonophobia, and a sense of just wanting to hide in a quiet dark room.
Stress/tension headaches are a generalized type of headache precipitated by stress. They are not one sided. They do not involve photophobia, nausea, vomiting, aura, or phonophobia.
CHRONIC DAILY HEADACHES occur on a daily basis and are often disabling. This type of headache may be challenging to diagnose and treat. Medication overuse, or drug rebound headache, is the most treatable form of refractory daily headache.
A 10-year-old female presents with severe headache and ataxia. Neuroracliologic imaging reveals a cystic tumor in

2. A 67-year-old woman who has been in very good health is brought to her physician's office by her husband. He states that over the course of the last 5 years, she has had difficulty recognizing her grandchildren; he must do all the planning for their daily activities; she forgets that she has things cooking on the stove; and at night he sometimes finds her wandering through the house with an "absent" look on her face. She is beginning to demonstrate difficulty in recalling the names of common objects, and her speech is limited to simple 2- or 3-word sentences. Question: What is the most likely diagnosis?

Alzheimer's disease

Amnestic disorder

Pseudodementia

Substance-Induced persisting dementia

Vascular dementia

This woman is suffering from dementia of the Alzheimer's type. A gradual onset of symptoms, general pervasive memory deficit, difficulties with language, and inability to plan, leading to severe impairment of daily functioning are all characteristic of dementia of the Alzheinner's type.
Amnestic disorder is limited to memory problems, and this woman is demonstrating cognitive dysfunction, such as alterations in language and the loss of the ability to plan.
Pseudodennentia is incorrect since it is a major depressive disorder rather than a dennenting condition. There is no evidence for a depressive syndrome in this patient's presentation.
The diagnosis of substance-induced persisting dementia requires evidence of a history of substance abuse. However, it is the second most likely diagnosis and should be carefully explored with the husband and other close relatives and friends.
Vascular dementia is generally characterized by a step-wise deterioration, not the gradual presentation of this case.

Explanation

This woman is suffering from dementia of the Alzheimer's type. A gradual onset of symptoms, general pervasive memory deficit, difficulties with language, and inability to plan, leading to severe impairment of daily functioning are all characteristic of dementia of the Alzheinner's type.
Amnestic disorder is limited to memory problems, and this woman is demonstrating cognitive dysfunction, such as alterations in language and the loss of the ability to plan.
Pseudodennentia is incorrect since it is a major depressive disorder rather than a dennenting condition. There is no evidence for a depressive syndrome in this patient's presentation.
The diagnosis of substance-induced persisting dementia requires evidence of a history of substance abuse. However, it is the second most likely diagnosis and should be carefully explored with the husband and other close relatives and friends.
Vascular dementia is generally characterized by a step-wise deterioration, not the gradual presentation of this case.

3. A 55-year-old male has had emotional changes consisting of sexual disinhibition and emotional apathy. He later has difficulty with expressing himself and doing his usual routine. The Magnetic Resonance Imaging (MR') reveals atrophy of the frontal and temporal lobes, along with swollen neurons in the temporal and frontal areas of the brain, and intraneuronal argentophilic inclusion bodies in these same areas. What type of dementia is this patient exhibiting?

Alzheimer disease

Dementia due to Parkinson's disease

Dementia due to Huntington's disease

Dementia due to Pick's disease

Dementia due to HIV disease

Dementia due to Pick's disease is a progressive neurodegenerative disease affecting the frontal and temporal lobes, which is characterized by frontal lobe involvement in which the patient may have emotional apathy or lability and disinhibition. The temporal lobe affectation is demonstrated by his problems with language and carrying out executive tasks. The symptoms usually appear between the ages of 50 to 60 years old. Usually the person exhibits some emotional disturbances in the beginning, and then years later, progresses into having problems with language and executive functioning. The cause of the disease is unknown. It can be diagnosed by the finding of intraneuronal argentophillc inclusions (Pick bodies) and swollen neurons (Pick cells) in the frontal and temporal areas of the brain. Functional neuroinnaging such as Positron Emisson Tomography (PET) show hypometaboiisnn in these regions before the atrophy occurs and becomes apparent on the MRI.
Dementia due to Alzheimer disease is another progressive neurodegenerative disease that, in contrast to the above, produces brain lesions. This type of dementia is seen in 55% of the cases of dementia. It occurs with more frequency in populations of increasing age. It is rarely seen in those younger than 50 years old. There seems to be a genetic predisposition especially seen on chromosomes 14, 19, and 21. Other factors may also be involved such as abnormal amyloid precursor protein metabolism, cholinergic neuronal dysfunction, and abnormal neuronal membrane phospholipid metabolism. In Alzheimer disease, the most affected areas are the mediotennporal lobes. There are deposits of tau protein in the neurons, which is associated with cellular microtubules in the neurofibrillary tangles. They are outside the neuron deposits of amyloid or aluminosilicate in the neocortex and hippocampus. The symptoms begin with mood and memory changes and then continue with delirium, delusions, and behavioral disturbances. They later cause gait disturbances, pathologic reflexes, and incontinence. Imaging would show diffuse frontotemporal atrophy, widened cortical sulci, and enlarged cerebral ventricles.
Dementia due to Parkinson's disease
is another progressive neurodegenerative disease in which the loss of doparninergic neurons in the substantia nigra causes symptoms such as progressive tremor, postural instability, and bradykinesia. The dementia is seen particularly in slow movements and clIfficulty carrying out executive functions. It is seen in 1 in 1,000 people and dementia is seen in 20% of the cases. Dementia is usually seen in people with an advanced stage of the disease. It should not be confused with the depression that may accompany the disease.
Dementia due to Huntington's disease
is another progressive neurodegenerative disease affecting neurons, but this time the GABA-ergic neurons cause choreoathetosis and dementia. It usually manifests by the age of 40. In the beginning, the person has personality changes and movement disturbances, then later they have slow thinking and problems with doing daily chores. Psychotic features are also common. This disease is associated with an autosomal dominant gene on chromosome 4. Neuroinnaging shows atrophy of the caudate nucleus with ventricular enlargement, or boxcar ventricles.
Dementia due to HIV disease
is caused by the destruction of the brain by the HIV virus. Diffuse multifocal destruction of brain structures occurs, which may lead to dementia in 30% of people with AIDS. Problems walking, hyperreflexia, increased tone and oculomotor deficits, and frontal release signs show motor dysfunction due to brain damage. CNS tumors and opportunistic CNS infections can also cause dementia and need to be ruled out.

Explanation

Dementia due to Pick's disease is a progressive neurodegenerative disease affecting the frontal and temporal lobes, which is characterized by frontal lobe involvement in which the patient may have emotional apathy or lability and disinhibition. The temporal lobe affectation is demonstrated by his problems with language and carrying out executive tasks. The symptoms usually appear between the ages of 50 to 60 years old. Usually the person exhibits some emotional disturbances in the beginning, and then years later, progresses into having problems with language and executive functioning. The cause of the disease is unknown. It can be diagnosed by the finding of intraneuronal argentophillc inclusions (Pick bodies) and swollen neurons (Pick cells) in the frontal and temporal areas of the brain. Functional neuroinnaging such as Positron Emisson Tomography (PET) show hypometaboiisnn in these regions before the atrophy occurs and becomes apparent on the MRI.
Dementia due to Alzheimer disease is another progressive neurodegenerative disease that, in contrast to the above, produces brain lesions. This type of dementia is seen in 55% of the cases of dementia. It occurs with more frequency in populations of increasing age. It is rarely seen in those younger than 50 years old. There seems to be a genetic predisposition especially seen on chromosomes 14, 19, and 21. Other factors may also be involved such as abnormal amyloid precursor protein metabolism, cholinergic neuronal dysfunction, and abnormal neuronal membrane phospholipid metabolism. In Alzheimer disease, the most affected areas are the mediotennporal lobes. There are deposits of tau protein in the neurons, which is associated with cellular microtubules in the neurofibrillary tangles. They are outside the neuron deposits of amyloid or aluminosilicate in the neocortex and hippocampus. The symptoms begin with mood and memory changes and then continue with delirium, delusions, and behavioral disturbances. They later cause gait disturbances, pathologic reflexes, and incontinence. Imaging would show diffuse frontotemporal atrophy, widened cortical sulci, and enlarged cerebral ventricles.
Dementia due to Parkinson's disease
is another progressive neurodegenerative disease in which the loss of doparninergic neurons in the substantia nigra causes symptoms such as progressive tremor, postural instability, and bradykinesia. The dementia is seen particularly in slow movements and clIfficulty carrying out executive functions. It is seen in 1 in 1,000 people and dementia is seen in 20% of the cases. Dementia is usually seen in people with an advanced stage of the disease. It should not be confused with the depression that may accompany the disease.
Dementia due to Huntington's disease
is another progressive neurodegenerative disease affecting neurons, but this time the GABA-ergic neurons cause choreoathetosis and dementia. It usually manifests by the age of 40. In the beginning, the person has personality changes and movement disturbances, then later they have slow thinking and problems with doing daily chores. Psychotic features are also common. This disease is associated with an autosomal dominant gene on chromosome 4. Neuroinnaging shows atrophy of the caudate nucleus with ventricular enlargement, or boxcar ventricles.
Dementia due to HIV disease
is caused by the destruction of the brain by the HIV virus. Diffuse multifocal destruction of brain structures occurs, which may lead to dementia in 30% of people with AIDS. Problems walking, hyperreflexia, increased tone and oculomotor deficits, and frontal release signs show motor dysfunction due to brain damage. CNS tumors and opportunistic CNS infections can also cause dementia and need to be ruled out.

4. A 32-year-old white female comes into your office. In taking a history she relates feeling well up until six months ago, when she started to feel tired all of the time and her hair and skin are dry. She goes on to say that her mother says her face looks puffy all of the time. She complains of vague aches, pairs, and complains of being cold all of the time and of not being able to concentrate. She also notes that she has been eating more because she feels a lack of energy. She states she has gained thirty pounds over the last year. Her medical history is significant for having a hysterectomy nine months ago. She is a G6 P5 SAB1. She also notes that she has been under a lot of stress since her husband has lost his job and has not found another one. Her vital signs are Temperature 97 oral - Pulses is 70 radial - respirations are 12 - blood pressure is 129/75. What is your working diagnosis?

Hypothyroidism

Hyperparathyroidism

Diabetes Mellitus I

Diabetes Mellitus ll

Cushing Disease

There are 2 types of hypothyroid, primary and congenital. Secondary hypothyroidism will affect all body systems. The onset is usually over months or years. The lower level of TH (thyroid hormone) is produced by the thyroid gland. Causes of secondary hypothyroidism can include insufficient stimulation of the normal gland, causing TSH (thyroid stimulating hormone) deficiency. There can also be a peripheral resistance to TH.
Clinical manifestations of hypothyroidism can include: confusion, syncope, slowed speech and thinking, memory loss, lethargy, headaches, hearing loss, night blindness, slow, clumsy movements, enlarged pituitary thyrotropes, decreased libido, dyspnea, myxedematous changes in respiratory muscles leading to hypoventilation and carbon dioxide retention, water retention, weight gain, slow movement, dry, flaky skin, dry, brittle, hair, and nnyxedema among other symptoms.
Treatment is based on clinical symptoms, and a decrease in serum T4 and free T4 nearly always is present. TSH concentration increases from loss of negative feedback from thyroid hormone. Hormone replacement therapy is the treatment of choice for hypothyroidism. It is available as a synthetic hormone (levothyroxine or liothyronine).
Hyperparathyroidism is a greater than normal secretion of parathyroid hormone (PTH). The reasons for primary hyperparathyroiclism are classified as either primary or secondary. Primary is a greater than normal secretion of PTH by one or more of the parathyroid glands. The normal feedback mechanisms, such as elevated serum levels of ionized calcium, fail to inhibit PTH secretion by the parathyroid gland. Secondary hyperparathyroidisnn occurs when there is an increase in PTH due to a chronic disease state, including chronic renal failure.
Clinical manifestations are excessive osteoclastic and osteocytic activity, resulting in bone resorption. Outward signs are pathologic fractures, kyphosis of the dorsal spine, and compression fractures of the vertebral bodies. Other symptoms are a greater than 6-month history of hypercalcennia, including kidney stones, hypophosphatemia, hyperchloremia, and increased urinary calcium levels. Treatment includes lowering of severely elevated calcium levels, increasing urinary calcium excretion with diuretics, and long-term management of hypercalcemia by use of drugs that decrease resorptIon of calcium from bone.
Groups of disease with glucose intolerance in common are often called Diabetes Mellitus. There are 2 recognized forms: one that affects obese individuals and another, which is found mainly among the young. The diagnosis of diabetes is based on one of the following: 1- fasting plasma glucose level > 126 mg/dL, 2- glucose value in the 2 hour sample (2hPG) of the standard oral glucose tolerance test (OGTT) of > 200 nng/dL, 3- a plasma glucose level >200 mg/dL anytime during the day, often with the classics symptoms of polydipsia, polyphagia, and polyuria. In Type I, the beta-cells fail, or the cause is idiopathic. In Type II, cells become insulin resistant with Inadequate insulin secretion. Symptoms of Type I are polydipsia, polyuria, polyphagia, weight loss, and fatigue, among others. Symptoms of Type II are often nonspecific. The individual is often over 30, over weight, dyslipidennic, hyperinsulinemic, and hypertensive. The onset tends to be slow and insidious. Other symptoms can include fatigue, pruritus, recurrent Infections, visual changes, or paresthesias.
Treatment for Type I includes control of blood sugars through frequent blood sugar checks and adjusting insulin, diet, and exercise to keep the blood sugars between 70 and 120. Treatment for Type II begins with weight loss, dietary management, and if need be, either oral or insulin medication. In Type II, exercise, in addition to the establishment and maintenance of nutritional therapy, can bring the disease under control.
Cushing Syndrome or Cushing Disease refers to chronic hypercortisolism (excessive levels of circulating cortisol). The usual cause is ectopic ACTH-secretIng tumors, or adrenal-secreting tumors. Signs and symptoms are thinning of scalp hair, faclal flush, moon face, purple striae on the abdomen, truncal obesity, thin extremities, easy bruising, and increased body and facial hair. Treatment is specific for the cause of hypercorticoadrenalism and includes medication, radiation, and surgery.

Explanation

There are 2 types of hypothyroid, primary and congenital. Secondary hypothyroidism will affect all body systems. The onset is usually over months or years. The lower level of TH (thyroid hormone) is produced by the thyroid gland. Causes of secondary hypothyroidism can include insufficient stimulation of the normal gland, causing TSH (thyroid stimulating hormone) deficiency. There can also be a peripheral resistance to TH.
Clinical manifestations of hypothyroidism can include: confusion, syncope, slowed speech and thinking, memory loss, lethargy, headaches, hearing loss, night blindness, slow, clumsy movements, enlarged pituitary thyrotropes, decreased libido, dyspnea, myxedematous changes in respiratory muscles leading to hypoventilation and carbon dioxide retention, water retention, weight gain, slow movement, dry, flaky skin, dry, brittle, hair, and nnyxedema among other symptoms.
Treatment is based on clinical symptoms, and a decrease in serum T4 and free T4 nearly always is present. TSH concentration increases from loss of negative feedback from thyroid hormone. Hormone replacement therapy is the treatment of choice for hypothyroidism. It is available as a synthetic hormone (levothyroxine or liothyronine).
Hyperparathyroidism is a greater than normal secretion of parathyroid hormone (PTH). The reasons for primary hyperparathyroiclism are classified as either primary or secondary. Primary is a greater than normal secretion of PTH by one or more of the parathyroid glands. The normal feedback mechanisms, such as elevated serum levels of ionized calcium, fail to inhibit PTH secretion by the parathyroid gland. Secondary hyperparathyroidisnn occurs when there is an increase in PTH due to a chronic disease state, including chronic renal failure.
Clinical manifestations are excessive osteoclastic and osteocytic activity, resulting in bone resorption. Outward signs are pathologic fractures, kyphosis of the dorsal spine, and compression fractures of the vertebral bodies. Other symptoms are a greater than 6-month history of hypercalcennia, including kidney stones, hypophosphatemia, hyperchloremia, and increased urinary calcium levels. Treatment includes lowering of severely elevated calcium levels, increasing urinary calcium excretion with diuretics, and long-term management of hypercalcemia by use of drugs that decrease resorptIon of calcium from bone.
Groups of disease with glucose intolerance in common are often called Diabetes Mellitus. There are 2 recognized forms: one that affects obese individuals and another, which is found mainly among the young. The diagnosis of diabetes is based on one of the following: 1- fasting plasma glucose level > 126 mg/dL, 2- glucose value in the 2 hour sample (2hPG) of the standard oral glucose tolerance test (OGTT) of > 200 nng/dL, 3- a plasma glucose level >200 mg/dL anytime during the day, often with the classics symptoms of polydipsia, polyphagia, and polyuria. In Type I, the beta-cells fail, or the cause is idiopathic. In Type II, cells become insulin resistant with Inadequate insulin secretion. Symptoms of Type I are polydipsia, polyuria, polyphagia, weight loss, and fatigue, among others. Symptoms of Type II are often nonspecific. The individual is often over 30, over weight, dyslipidennic, hyperinsulinemic, and hypertensive. The onset tends to be slow and insidious. Other symptoms can include fatigue, pruritus, recurrent Infections, visual changes, or paresthesias.
Treatment for Type I includes control of blood sugars through frequent blood sugar checks and adjusting insulin, diet, and exercise to keep the blood sugars between 70 and 120. Treatment for Type II begins with weight loss, dietary management, and if need be, either oral or insulin medication. In Type II, exercise, in addition to the establishment and maintenance of nutritional therapy, can bring the disease under control.
Cushing Syndrome or Cushing Disease refers to chronic hypercortisolism (excessive levels of circulating cortisol). The usual cause is ectopic ACTH-secretIng tumors, or adrenal-secreting tumors. Signs and symptoms are thinning of scalp hair, faclal flush, moon face, purple striae on the abdomen, truncal obesity, thin extremities, easy bruising, and increased body and facial hair. Treatment is specific for the cause of hypercorticoadrenalism and includes medication, radiation, and surgery.

5. A 40-year-old woman comes to your office presenting with anxiety, difficulty sleeping, rapid heartbeat, and tremor in her hands. You note the presence of bulging eyes and suspect Graves disease. You confirm that she has this disease by determining the blood levels of:

Thyroid stimulating hormone

Thyroid peroxidase

Protein-bound iodine

Thyroglobulin

Thyrotropin-releasing hormone

Graves' disease is a type of hyperthyroidism caused by a generalized over-activity of the entire thyroid gland. The patient appears hot and flushed and the thyroid gland enlarges in this condition. It Is believed that Graves' disease is an autoimnnune disorder. Antibodies are produced against certain proteins on the surface of thyroid cells, stimulating those cells to overproduce thyroid hormones. In this condition antibodies are produced against the thyrotropin receptor, thyroglobulin, thyroid peroxidase, and sodium-iodide symporter. The crculating auto- antibodies continuously stimulate the thyroid gland via the thyrotropin receptor. Associated suppression of the pituitary thyrotropin level is due to increased production of thyroid hormones. The onset of the disease is gradual and the symptoms may be mistaken for nervousness due to a stressful life situation. Weight loss occurs followed by other symptoms such as trembling, muscle weakness of the upper arms and thighs, and insomnia. The pituitary gland releases Thyroid Stimulating Hormone (TSH) in response to insufficient levels of thyroid hormone. Communication between the pituitary gland and the thyroid gland through TSH levels controls the levels of thyroid hormone in the blood. If the levels of thyroid hormone are low then the levels of TSH will rise. The measurement of TSH in the blood is taken as a measure of thyroid function. In Graves' disease there is a suppressed level of thyrotropin along with elevated levels of free T4 or T3 hormone levels. The new generation (III generation) assay of TSH is very sensitive and has revolutionized diagnosis of Graves' disease by providing accurate measurements of very low TSH levels. Suppression of TSH is an early and highly sensitive marker of thyrotoxicosis. Estimation of thyroid peroxidase, protein-bound iodine, thyroglobulin, and thyrotropin-releasing hormone are not as reliable as TSH assay.

Explanation

Graves' disease is a type of hyperthyroidism caused by a generalized over-activity of the entire thyroid gland. The patient appears hot and flushed and the thyroid gland enlarges in this condition. It Is believed that Graves' disease is an autoimnnune disorder. Antibodies are produced against certain proteins on the surface of thyroid cells, stimulating those cells to overproduce thyroid hormones. In this condition antibodies are produced against the thyrotropin receptor, thyroglobulin, thyroid peroxidase, and sodium-iodide symporter. The crculating auto- antibodies continuously stimulate the thyroid gland via the thyrotropin receptor. Associated suppression of the pituitary thyrotropin level is due to increased production of thyroid hormones. The onset of the disease is gradual and the symptoms may be mistaken for nervousness due to a stressful life situation. Weight loss occurs followed by other symptoms such as trembling, muscle weakness of the upper arms and thighs, and insomnia. The pituitary gland releases Thyroid Stimulating Hormone (TSH) in response to insufficient levels of thyroid hormone. Communication between the pituitary gland and the thyroid gland through TSH levels controls the levels of thyroid hormone in the blood. If the levels of thyroid hormone are low then the levels of TSH will rise. The measurement of TSH in the blood is taken as a measure of thyroid function. In Graves' disease there is a suppressed level of thyrotropin along with elevated levels of free T4 or T3 hormone levels. The new generation (III generation) assay of TSH is very sensitive and has revolutionized diagnosis of Graves' disease by providing accurate measurements of very low TSH levels. Suppression of TSH is an early and highly sensitive marker of thyrotoxicosis. Estimation of thyroid peroxidase, protein-bound iodine, thyroglobulin, and thyrotropin-releasing hormone are not as reliable as TSH assay.

6. A 65-year-old woman has a long-standing dementing disorder characterized by deterioration in personality, neglect of personal hygiene, impaired judgment, and uninhibited behavior. MRI demonstrates severe cortical atrophy limited to the frontal lobes and anterior two thirds of the temporal lobes, while the remaining cortex is preserved. No evidence of recent or remote infarcts is found. Question: What diagnosis is most consistent with these pathologic and clinical features?

Alzheimers dz

Creutzfeldt-Jacob dz

Dementia with Lewy bodies

Frontotemporal dementia

Vascular demntia

Picks

Not all dementing disorders manifest with the same clinical features. Although there is considerable overlap in clinical symptomatology among different types of dennentias, making clinical diagnosis somewhat problematic, there are classic presentations that allow identification of a specific form of dementia with a high degree of confidence. In this case, the patient has symptoms due to frontal lobe damage, e.g., disinhibition, impaired judgment, and personality changes. Furthermore, MRI demonstrates a specific pattern of cortical atrophy, restricted to the frontal lobes and anterior portion of the temporal lobes. This combination points toward a group of dementias called frontotemporal dementia, the most frequent form of which is Pick disease. Other forms of frontotemporal dementia are very infrequent. Remember: frontal symptoms in conjunction with frontotennporal atrophy = frontotemporal dementia/Pick disease.
Alzheimer's disease is the most frequent form of dementia in industrialized countries. Although symptoms due to frontal damage may be present in Alzheimer's disease, they are usually associated with a more generalized impairment of higher neurologic functions, e.g., language, memory, and learned movements. In addition, cortical atrophy in Alzheimer's disease is widespread and not limited to the frontal and anterior temporal lobes.
Creutzfeldt-Jacob disease represents the prototype of prion diseases. Cortical atrophy is not a prominent feature of Creutzfeldt-Jacob disease, which manifests with personality changes, memory loss, and seizures, leading to death after a rapid clinical course (a few months to 1 year).
Dementia with Lewy bodies, also known as diffuse Lewy body disease, is one of the most common forms of dementia in Western countries, possibly more common than vascular dementia. It is characterized by widespread formation of Lewy bodies in the substantia nIgra, limbic cortex, and subcortical nuclei, such as the basal nucleus of Meynert. Extrapyrannidal symptoms similar to Parkinson's disease manifest in this form of dementia as a result of degeneration of dopamlnergic pathways.
Vascular dementia is an umbrella term encompassing dementing conditions that arise from pathology of large or small cerebral vessels. It manifests with memory loss associated with focal neurologic symptoms depending on the location of damage. MRI would identify old or recent infarcts, as well as white matter disease. Conditions associated with vascular dementia include the following: multi-infarct dementia, which is caused by multiple, scattered brain infarcts secondary to atherosclerosis of large arteries of the circle of Willis and/or carotid arteries; Binswanger disease, which involves rarefaction of cerebral white matter and is caused by hypertension-related arteriolosclerosis; lacunar infarcts, which consist of small (

Explanation

Not all dementing disorders manifest with the same clinical features. Although there is considerable overlap in clinical symptomatology among different types of dennentias, making clinical diagnosis somewhat problematic, there are classic presentations that allow identification of a specific form of dementia with a high degree of confidence. In this case, the patient has symptoms due to frontal lobe damage, e.g., disinhibition, impaired judgment, and personality changes. Furthermore, MRI demonstrates a specific pattern of cortical atrophy, restricted to the frontal lobes and anterior portion of the temporal lobes. This combination points toward a group of dementias called frontotemporal dementia, the most frequent form of which is Pick disease. Other forms of frontotemporal dementia are very infrequent. Remember: frontal symptoms in conjunction with frontotennporal atrophy = frontotemporal dementia/Pick disease.
Alzheimer's disease is the most frequent form of dementia in industrialized countries. Although symptoms due to frontal damage may be present in Alzheimer's disease, they are usually associated with a more generalized impairment of higher neurologic functions, e.g., language, memory, and learned movements. In addition, cortical atrophy in Alzheimer's disease is widespread and not limited to the frontal and anterior temporal lobes.
Creutzfeldt-Jacob disease represents the prototype of prion diseases. Cortical atrophy is not a prominent feature of Creutzfeldt-Jacob disease, which manifests with personality changes, memory loss, and seizures, leading to death after a rapid clinical course (a few months to 1 year).
Dementia with Lewy bodies, also known as diffuse Lewy body disease, is one of the most common forms of dementia in Western countries, possibly more common than vascular dementia. It is characterized by widespread formation of Lewy bodies in the substantia nIgra, limbic cortex, and subcortical nuclei, such as the basal nucleus of Meynert. Extrapyrannidal symptoms similar to Parkinson's disease manifest in this form of dementia as a result of degeneration of dopamlnergic pathways.
Vascular dementia is an umbrella term encompassing dementing conditions that arise from pathology of large or small cerebral vessels. It manifests with memory loss associated with focal neurologic symptoms depending on the location of damage. MRI would identify old or recent infarcts, as well as white matter disease. Conditions associated with vascular dementia include the following: multi-infarct dementia, which is caused by multiple, scattered brain infarcts secondary to atherosclerosis of large arteries of the circle of Willis and/or carotid arteries; Binswanger disease, which involves rarefaction of cerebral white matter and is caused by hypertension-related arteriolosclerosis; lacunar infarcts, which consist of small (

7. A 36-y/o man complains of excessive thirst for the past few days. He consumes 3 to 4 liters of water per day but is still thirsty. He has also been passing urine very frequently. He has been started on lithium for bipolar disorder a few months back. Blood glucose is normal. Urine specific gravity and osmolality are 1.002 and 180 mOsm/kg, respectively. There is no increase in urine osmolality with exogenous antidiuretic hormone (ADH) administration. What is the probable diagnosis?

Idiopathic central diabetes insipidus

Familial central diabetes irsipidus

Acquired central diabetes insipidus

Hereditary nephrogenic diabetes insipid us

Acquired nephrogenic diabetes insipidus

The correct answer is acquired nephrogenic diabetes insipidus. Diabetes insipidus (DI) is a condition of excessive thirst and urination. It may be neurogenic (central) or nephrogenic.
Nephrogenic diabetes insipidus is caused by a resistance to the antidiuretic hormone (ADH) in the kidney. It may be hereditary, which is rare, or acquired. Acquired nephrogenic DI may be caused by lithium toxicity, chronic renal disease, hypercalcemia, etc.
Central DI is characterized by decreased ADH secretion, resulting in the persons' decreased ability to concentrate urine. Causes include tumors of the pituitary, head trauma, and neurosurgery. It may also be idiopathic or familial. Idiopathic central DI is believed to be an autoirnmune condition with destruction of cells in the hypothalamus. Familial central DI is rare.
ADH administration causes an increase in urine osmolality in central DI but not in nephrogenic DI.
A history of lithium use makes acquired nephrogenIc DI more likely than hereditary nephrogenic DI in this patient.

Explanation

The correct answer is acquired nephrogenic diabetes insipidus. Diabetes insipidus (DI) is a condition of excessive thirst and urination. It may be neurogenic (central) or nephrogenic.
Nephrogenic diabetes insipidus is caused by a resistance to the antidiuretic hormone (ADH) in the kidney. It may be hereditary, which is rare, or acquired. Acquired nephrogenic DI may be caused by lithium toxicity, chronic renal disease, hypercalcemia, etc.
Central DI is characterized by decreased ADH secretion, resulting in the persons' decreased ability to concentrate urine. Causes include tumors of the pituitary, head trauma, and neurosurgery. It may also be idiopathic or familial. Idiopathic central DI is believed to be an autoirnmune condition with destruction of cells in the hypothalamus. Familial central DI is rare.
ADH administration causes an increase in urine osmolality in central DI but not in nephrogenic DI.
A history of lithium use makes acquired nephrogenIc DI more likely than hereditary nephrogenic DI in this patient.

8. A 65-year-old Caucasian man has a 40-pack-year history of cigarette smoking. He is found to have a spot on his lung after a chest X-ray. A biopsy confirms that he has small cell carcinoma of the lung, and he is admitted to the hospital. Over the course of the next few days, he develops lethargy and confusion and then proceeds to have a seizure. His urine output remains normal. Laboratory tests are performed or his blood and his urine. The results are as follows:

TEST	RESULTS	REFERENCE RANGE i
glucose (fasting)	72 mg/dL	65-110 mg/dL
sodium	121 mEq/L	135-145 mEq/L
potassium	4.0 nnEq/L	3.5-5.0 mEq/L
BUN	11.2 mg/dL	10-20 mg/dL
urine dipstick blood	negative	negative
urine dipstick glucose	negative	negative
urine dipstick ketones	negative	negative
urine dipstick protein	negative 1.055	negative
urine specific gravity	negative 1.055	1.001 - 1.035

Question: Water restriction is started and his symptoms improve. What is the most likely diagnosis?

SIADH

Diabetes Mellitus

Diabetes Insipidus

Psychogenic polydipsia

Oliguria

Serum hypo-osmolality and serum hyponatremia can be seen with the syndrome of inappropriate ADH secretion (SIADH). The specific gravity of his urine is elevated. The urine is hyperosmotic, which is also consistent with SIADH. This condition can be treated by water restriction. Small cell carcinoma of the lung is a common disease associated with SIADH.
Serum osmolality can be estimated by:
2(NA + K) + urea/2.8 + glucose/18
Note: Sometimes the potassium is ignored in this equation.
The estimate of his serum osnnolality is 250-258 nnOsm/kg. His serum osmolality is low; the normal range is 270- 290 nnOsm/kg. He is hyponatremic, which is the cause of his hypo-osmolality.
Glucose would be found in the urine of a patient with uncontrolled diabetes mellitus. Blood glucose level would be elevated.
Polyuria and polydipsia are associated with diabetes insipidus. The urine would have a low specific gravity and his blood would have an elevated osmolality.
A patient with psychogenic polydipsia also would drink large amounts of water and have a large urine output. Oliguria is defined as scanty urine output.

Explanation

Serum hypo-osmolality and serum hyponatremia can be seen with the syndrome of inappropriate ADH secretion (SIADH). The specific gravity of his urine is elevated. The urine is hyperosmotic, which is also consistent with SIADH. This condition can be treated by water restriction. Small cell carcinoma of the lung is a common disease associated with SIADH.
Serum osmolality can be estimated by:
2(NA + K) + urea/2.8 + glucose/18
Note: Sometimes the potassium is ignored in this equation.
The estimate of his serum osnnolality is 250-258 nnOsm/kg. His serum osmolality is low; the normal range is 270- 290 nnOsm/kg. He is hyponatremic, which is the cause of his hypo-osmolality.
Glucose would be found in the urine of a patient with uncontrolled diabetes mellitus. Blood glucose level would be elevated.
Polyuria and polydipsia are associated with diabetes insipidus. The urine would have a low specific gravity and his blood would have an elevated osmolality.
A patient with psychogenic polydipsia also would drink large amounts of water and have a large urine output. Oliguria is defined as scanty urine output.

9. A 33-year-old female visits a physician complaining of weight loss in spite of a hearty appetite. At first glance the physician notices her large eyes. She gives a history of increased anxiety over the last few months associated with palpitations and diaphoresis. During the examination, the physician notes tachycardia, hypertension, sweaty palms, and trembling outstretched hands. There is a diffuse swelling in the neck with a bruit heard on auscultation. What is the most likely diagnosis?

Hashimoto's thyroiditis

Hypothyroidism

Parathyroid adenoma

Lateral aberrant thyroid

Graves disease

Hyperthyroidism

Graves disease is an idiopathic autoinnmune disorder associated with HLA-38 and HLA-DR3. It is characterized by hyperthyroidism and a diffuse swelling of the thyroid (which moves with deglutition); hence, It also called diffuse toxic goiter.
Hashimoto's thyroiditis and hypothyroidism are associated with lowered levels of thyroxine and its related symptoms, whereas this patient is showing signs of hyperthyroidism. The features that distinguish graves disease from other causes of hyperthyroidism are given below.
Lateral aberrant thyroid is a unique presentation of carcinoma thyroid wherein the lymph node metastasis is detected before the primary.
Commonest clinical features of Hyperthyroidism are: GIT:
• Wt. Loss
• Fatigue
• Anorexia
CARDIORESPIRATORY:
• Dyspnea on exertion
• Palpitations
CNS:
• Emotional lability
• Tumor
• Hyper-reflexa
DERMATOLOGICAL:
• Palnnar erythema
• Alopecia
• Increased sweating
REPRODUCTIVE:
• Amenorrhea / oligomenorrhea
• Infertility
• Impotence
• Decreased libido
OTHER:
• Heat intolerance
• Hyper defecation
• Apathy
Clinical features specific to Graves Disease:
OCULAR:
• Lid lag
• Excess lacrimation
• Chemosis
• Exophthalrnos
• Corneal ulceration
• Diplopia and ophthalmoplegia
• Papilledenna
• Decrease visual acuity
DERMATOLOGICAL:
• Vitiligo
• Clubbing
• Pretibial myxedema
OTHER:
• Lymphadenopathy
• Diffuse goitre with bruit

Explanation

Graves disease is an idiopathic autoinnmune disorder associated with HLA-38 and HLA-DR3. It is characterized by hyperthyroidism and a diffuse swelling of the thyroid (which moves with deglutition); hence, It also called diffuse toxic goiter.
Hashimoto's thyroiditis and hypothyroidism are associated with lowered levels of thyroxine and its related symptoms, whereas this patient is showing signs of hyperthyroidism. The features that distinguish graves disease from other causes of hyperthyroidism are given below.
Lateral aberrant thyroid is a unique presentation of carcinoma thyroid wherein the lymph node metastasis is detected before the primary.
Commonest clinical features of Hyperthyroidism are: GIT:
• Wt. Loss
• Fatigue
• Anorexia
CARDIORESPIRATORY:
• Dyspnea on exertion
• Palpitations
CNS:
• Emotional lability
• Tumor
• Hyper-reflexa
DERMATOLOGICAL:
• Palnnar erythema
• Alopecia
• Increased sweating
REPRODUCTIVE:
• Amenorrhea / oligomenorrhea
• Infertility
• Impotence
• Decreased libido
OTHER:
• Heat intolerance
• Hyper defecation
• Apathy
Clinical features specific to Graves Disease:
OCULAR:
• Lid lag
• Excess lacrimation
• Chemosis
• Exophthalrnos
• Corneal ulceration
• Diplopia and ophthalmoplegia
• Papilledenna
• Decrease visual acuity
DERMATOLOGICAL:
• Vitiligo
• Clubbing
• Pretibial myxedema
OTHER:
• Lymphadenopathy
• Diffuse goitre with bruit

10. A 40-year-old Caucasian woman presents to your office with difficulty swallowing and hoarseness. On further questioning, she acknowedges a history of therapeutic radiation to her neck as a child. On physical examination, you detect a solitary thyroid nodule. A thyroid biopsy is done, and the results indicate a malignancy. The pathologist comments on the presence of psammoma bodies. He also comments on the presence of distinctive ground glass nuclei resembling "Orphan Annie eyes." Which of the following is most likely?

Thyroid adenoma

Follicular Carcinoma

Anaplastic carcinoma

Medullary carcinoma

Papillary carcinoma

The history of neck radiation during her childhood puts this patient at an increased risk for the development of thyroid cancer.
Papillary carcinoma is the most frequently occurring malignancy of the thyroid gland. On histologic examination, psarnmorna bodies and ground glass nuclei ("Orphan Annie eyes") can be seen with papillary thyroid carcinoma. Papillary carcinoma has the best prognosis of the thyroid malignancies.
Thyroid adenoma is a benign tumor; it is not a malignancy of the thyroid.
Follicular carcinoma is the second most frequently occurring thyroid malignancy. On histologic examination, follicles or rudimentary follicles can be seen with follicular carcinoma.
Anaplastic carcinoma occurs much less frequently than papillary carcinoma or follicular carcinoma. On histologic examination, anaplastic carcinoma is undifferentiated. Of the thyroid malignancies, anaplastic carcinoma has the poorest prognosis.
Medullary carcinoma occurs much less frequently than papillary carcinoma or follicular carcinoma. Medullary carcinomas originate from the parafollicular C cells. On histologic examination, medullary carcinoma would demonstrate small round cells.

Explanation

The history of neck radiation during her childhood puts this patient at an increased risk for the development of thyroid cancer.
Papillary carcinoma is the most frequently occurring malignancy of the thyroid gland. On histologic examination, psarnmorna bodies and ground glass nuclei ("Orphan Annie eyes") can be seen with papillary thyroid carcinoma. Papillary carcinoma has the best prognosis of the thyroid malignancies.
Thyroid adenoma is a benign tumor; it is not a malignancy of the thyroid.
Follicular carcinoma is the second most frequently occurring thyroid malignancy. On histologic examination, follicles or rudimentary follicles can be seen with follicular carcinoma.
Anaplastic carcinoma occurs much less frequently than papillary carcinoma or follicular carcinoma. On histologic examination, anaplastic carcinoma is undifferentiated. Of the thyroid malignancies, anaplastic carcinoma has the poorest prognosis.
Medullary carcinoma occurs much less frequently than papillary carcinoma or follicular carcinoma. Medullary carcinomas originate from the parafollicular C cells. On histologic examination, medullary carcinoma would demonstrate small round cells.

11. An 8-year-old male presents with projectile vomiting, severe headache and ataxia. CSF examination shows small cells with hyperchromatic nucleus microscopically. CT scan reveals a 4-cm mass in the cerebellar vermis. The excised mass shows an intensely cellular tumor comprised of small cells with scanty cytoplasm and ill-defined borders. Mitoses are readily observed. The nuclei are hyperchronnatic and have an irregular membrane with an angular to ovoid shape. What is the most likely diagnosis?

Medulloblastoma

Neuroblastoma

Cerebellar Astrocytoma

Ependymoma

Oligodendroglioma

MEDULLOBLASTOMA is the most frequently encountered intracranial neuroectoclermal tumor in children. Microscopically, medulloblastoma reveals a primitive small-celled malignant tumor forming Homer-Wright rosettes. The nuclei are closely packed, hyperchromatic, relatively uniform and round, oval, or carrot shaped. Dissemination through the CSF is a common complication. The tumor is highly malignant. However, the tumor is very radiosensitive. With total excision and radiation, the 5-year survival rate is as high as 75%.
NEUROBLASTOMA is one of the common solid tumors of childhood and can arise from adrenals or extra-adrenal sites. Cerebellar neuroblastomas are rare, and they arise in the early part of the first decade and show a highly aggressive clinical behavior. The majority are supratentorial, massive, and multicystic. Histologically, they are highly cellular, showing cells that are small with hyperchromatic nuclei and are arranged in solid sheets. A slightly fibrillated matrix traversed by delicate neurites is characteristic. They are negative for GFAP and do not stain with PTAH indicating the absence of glial component. Characteristic Homer-Wright rosettes with tumor cells at the periphery and young nerve fibrils at the center may be present.
CEREBELLAR ASTROCYTOMA predominantly occurs in children. They are characterized by a biphasic pattern. There are bipolar fibrillated and elongated cells packed in bundles with perivascular arrangements and there are stellate cells with short processes with a lacy pattern and show microcystic changes. Also seen are Rosenthal fibers, granular hyaline deposits, and eosinophilic intracytoplasmic bodies. These tumors grow slowly and have a benign course.
OLIGODENDROGLIOMAS constitute about 5 to 15% of gliomas and are most common in the fourth and fifth decades. The lesions are found in cerebral hemispheres, with a predilection for the white matter. Grossly, they are well- circumscribed, gelatinous, often with cyst formation, areas of hemorrhage and calcification. Microscopically, they are characterized by round cells with a small darkly staining nucleus, clear cytoplasm, and clearly defined cell membrane. In general, they have a better prognosis than astrocytomas.
EPENDYMOMAS most often arise next to the ependyma lined ventricular system. They commonly occur near the 4th ventricle in the first 2 decades and in spinal cord in adults. Microscopically, they are characterized by ependymal rosettes, which are duct-like structures with a round or elongated central lumen around which columnar cells are arranged concentrically with basal nuclei.

Explanation

MEDULLOBLASTOMA is the most frequently encountered intracranial neuroectoclermal tumor in children. Microscopically, medulloblastoma reveals a primitive small-celled malignant tumor forming Homer-Wright rosettes. The nuclei are closely packed, hyperchromatic, relatively uniform and round, oval, or carrot shaped. Dissemination through the CSF is a common complication. The tumor is highly malignant. However, the tumor is very radiosensitive. With total excision and radiation, the 5-year survival rate is as high as 75%.
NEUROBLASTOMA is one of the common solid tumors of childhood and can arise from adrenals or extra-adrenal sites. Cerebellar neuroblastomas are rare, and they arise in the early part of the first decade and show a highly aggressive clinical behavior. The majority are supratentorial, massive, and multicystic. Histologically, they are highly cellular, showing cells that are small with hyperchromatic nuclei and are arranged in solid sheets. A slightly fibrillated matrix traversed by delicate neurites is characteristic. They are negative for GFAP and do not stain with PTAH indicating the absence of glial component. Characteristic Homer-Wright rosettes with tumor cells at the periphery and young nerve fibrils at the center may be present.
CEREBELLAR ASTROCYTOMA predominantly occurs in children. They are characterized by a biphasic pattern. There are bipolar fibrillated and elongated cells packed in bundles with perivascular arrangements and there are stellate cells with short processes with a lacy pattern and show microcystic changes. Also seen are Rosenthal fibers, granular hyaline deposits, and eosinophilic intracytoplasmic bodies. These tumors grow slowly and have a benign course.
OLIGODENDROGLIOMAS constitute about 5 to 15% of gliomas and are most common in the fourth and fifth decades. The lesions are found in cerebral hemispheres, with a predilection for the white matter. Grossly, they are well- circumscribed, gelatinous, often with cyst formation, areas of hemorrhage and calcification. Microscopically, they are characterized by round cells with a small darkly staining nucleus, clear cytoplasm, and clearly defined cell membrane. In general, they have a better prognosis than astrocytomas.
EPENDYMOMAS most often arise next to the ependyma lined ventricular system. They commonly occur near the 4th ventricle in the first 2 decades and in spinal cord in adults. Microscopically, they are characterized by ependymal rosettes, which are duct-like structures with a round or elongated central lumen around which columnar cells are arranged concentrically with basal nuclei.

12. A 10-year-old female presents with severe headache and ataxia. Neuroradiologic imaging reveals a cystic tumor in the cerebellum. Microscopically, the excised tumor shows a biphasc pattern. There are bipolar fibrillated and elongated cells packed in bundles with perivascular arrangements. There are stellate cells with short processes with a lacy pattern and areas showing microcystic changes. Also seen are Rosenthal fibers, granular hyaline deposits, and eosinophilic intracytoplasmic bodies. What is the most Likely diagnosis?

Medulloblastoma

Neuroblastoma

Cerebellar Astrocytoma

Ependymoma

Oligodendroglioma

MEDULLOBLASTOMA is the most frequently encountered intracranial neuroectodermal tumor in children. Microscopically, medulloblastoma reveals a primitive small-celled malignant tumor forming Homer-Wright rosettes. The nuclei are closely packed, hyperchromatic, relatively uniform and round, oval, or carrot shaped. Dissemination through the CSF is a common complication. The tumor is highly malignant. However, the tumor is very radiosensitive. With total excision and radiation, the 5-year survival rate is as high as 75%.
NEUROBLASTOMA is one of the common solid tumors of childhood and can arise from adrenals or extra-adrenal sites. Cerebellar neuroblastomas are rare, and they arise in the early part of the first decade and show a highly aggressive clinical behavior. The majority are supratentorial, massive, and multicystic. Histologically, they are highly cellular, showing cells that are small with hyperchromatic nuclei and are arranged in solid sheets. A slightly fibrillated matrix traversed by delicate neurites is characteristic. They are negative for GFAP and do not stain with PTAH indicating the absence of glial component. Characteristic Homer-Wright rosettes with tumor cells at the periphery and young nerve fibrils at the center may be present.
CEREBELLAR ASTROCYTOMA predominantly occurs in children. They are characterized by a biphasic pattern. There are bipolar fibrillated and elongated cells packed in bundles with perivascular arrangements and there are stellate cells with short processes with a lacy pattern and show microcystic changes. Also seen are Rosenthal fibers, granular hyaline deposits, and eosinophilic intracytoplasmic bodies. These tumors grow slowly and have a benign course.
OLIGODENDROGLIOMAS constitute about 5 to 15% of gliomas and are most common in the fourth and fifth decades. The lesions are found in cerebral hemispheres, with a predilection for the white matter. Grossly, they are well- circumscribed, gelatinous, often with cyst formation, areas of hemorrhage and calcification. Microscopically, they are characterized by round cells with a small darkly staining nucleus, clear cytoplasm, and clearly defined cell membrane. In general, they have a better prognosis than astrocytomas.
EPENDYMOMAS most often arise next to the ependyma lined ventricular system. They commonly occur near the 4th ventricle in the first 2 decades and in spinal cord in adults. Microscopically, they are characterized by ependymal rosettes, which are duct-like structures with a round or elongated central lumen around which columnar cells are arranged concentrically with basal nuclei.

Explanation

MEDULLOBLASTOMA is the most frequently encountered intracranial neuroectodermal tumor in children. Microscopically, medulloblastoma reveals a primitive small-celled malignant tumor forming Homer-Wright rosettes. The nuclei are closely packed, hyperchromatic, relatively uniform and round, oval, or carrot shaped. Dissemination through the CSF is a common complication. The tumor is highly malignant. However, the tumor is very radiosensitive. With total excision and radiation, the 5-year survival rate is as high as 75%.
NEUROBLASTOMA is one of the common solid tumors of childhood and can arise from adrenals or extra-adrenal sites. Cerebellar neuroblastomas are rare, and they arise in the early part of the first decade and show a highly aggressive clinical behavior. The majority are supratentorial, massive, and multicystic. Histologically, they are highly cellular, showing cells that are small with hyperchromatic nuclei and are arranged in solid sheets. A slightly fibrillated matrix traversed by delicate neurites is characteristic. They are negative for GFAP and do not stain with PTAH indicating the absence of glial component. Characteristic Homer-Wright rosettes with tumor cells at the periphery and young nerve fibrils at the center may be present.
CEREBELLAR ASTROCYTOMA predominantly occurs in children. They are characterized by a biphasic pattern. There are bipolar fibrillated and elongated cells packed in bundles with perivascular arrangements and there are stellate cells with short processes with a lacy pattern and show microcystic changes. Also seen are Rosenthal fibers, granular hyaline deposits, and eosinophilic intracytoplasmic bodies. These tumors grow slowly and have a benign course.
OLIGODENDROGLIOMAS constitute about 5 to 15% of gliomas and are most common in the fourth and fifth decades. The lesions are found in cerebral hemispheres, with a predilection for the white matter. Grossly, they are well- circumscribed, gelatinous, often with cyst formation, areas of hemorrhage and calcification. Microscopically, they are characterized by round cells with a small darkly staining nucleus, clear cytoplasm, and clearly defined cell membrane. In general, they have a better prognosis than astrocytomas.
EPENDYMOMAS most often arise next to the ependyma lined ventricular system. They commonly occur near the 4th ventricle in the first 2 decades and in spinal cord in adults. Microscopically, they are characterized by ependymal rosettes, which are duct-like structures with a round or elongated central lumen around which columnar cells are arranged concentrically with basal nuclei.

13. A 72-year-old retired nurse with type II diabetes and arthritis, was brought in to see her physician by her two daughters. Although unconcerned herself, her daughters were worried that something may be wrong with her. They informed the doctor that she hadn it been herself for the past 6 months or so. They described their mothers personality as changing drastically. For example, she now laughed inappropriately and seemed utterly unconcerned with things that had previously interested her. After a normal physical examination, her physician referred her to a neurologist. Upon examination, the neurologist detected nothing unusual. All cranial nerves seemed intact and functional. Based on the patiertis symptoms, the neurologist suspected a tumor. An MRI-scan was ordered, which revealed an abnormal intracranial mass. If this tumor was found to be noninvasive and easily susceptible to complete surgical resection, it is MOST likely which of the following types of tumors?

Glioma

Astrocytoma

Meningionna

Pinealoma

Acoustic neuronna

Meningiomas are generally benign, encapsulated tumors that once diagnosed, can be completely removed surgically, although meningiomas in the area of the brainstem may be more difficult to remove. Meningiomas typically compress the underlying cerebral cortex, leading to cortical dysfunction of that particular area. In this case, our patient likely suffered from a frontal lobe meningioma. Astrocytonnas (gliomas) are very invasive and are not typically susceptible to surgical resection. Acoustic neuroma and pinealonnas are more difficult to remove surgically and the surgery is not without its consequences. For instance, removal of an acoustic neuroma typically causes facial paralysis and deafness.

Explanation

Meningiomas are generally benign, encapsulated tumors that once diagnosed, can be completely removed surgically, although meningiomas in the area of the brainstem may be more difficult to remove. Meningiomas typically compress the underlying cerebral cortex, leading to cortical dysfunction of that particular area. In this case, our patient likely suffered from a frontal lobe meningioma. Astrocytonnas (gliomas) are very invasive and are not typically susceptible to surgical resection. Acoustic neuroma and pinealonnas are more difficult to remove surgically and the surgery is not without its consequences. For instance, removal of an acoustic neuroma typically causes facial paralysis and deafness.

14. A 54-year-old white male presents with gradual onset of mild dementia, ataxic gait, and startle myoclonus. An MRI scan is normal, and an examination of his cerebrospinal fluid reveals no abnormalities, but the patient's EEG is remarkable for recurrent bursts of high -voltage slow waves. Over the next 6 months, the patient's dementia rapidly worsens, accompanied by general hypertonicity and profound dysarthria. The patient dies shortly thereafter. What is the most likely neuropathological finding on autopsy?

Cerebellar hyperplasia

Diffuse spongiform change

Multiple lacunar infarcts

Negri bodies

Neurofibrillary tangles

(B) The rapidly progressive dementia in this case is characteristic of Creutzfeldt-Jakob disease (CJD). The dementia is usually accompanied by motor dysfunction and abnormal EEG activity, as described in the question stem. The pathological hallmark of this disease is spongiforrn change in the gray matter. Death usually occurs within 6-12 months of disease onset.
At autopsy, the cerebellum in CJD appears atrophic, not hyperplastic.
Multiple lacunar infarcts are seen with vascular dementia, and patients typically present with focal neurological signs. Additionally, vascular dementia typically presents with a more gradual decline in cognitive function, measured in years rather than months.
Negri bodies are pathognornic for rabies, which does not cause dementia.
Neurofibrillary tangles are often seen in patients with Alzheimer's disease. Alzheimer's disease primarily affects the higher order association cortex; motor dysfunction is not generally observed. Additionally, in Alzheimer's disease, there is a more gradual decline in cognitive function, measured in years rather than months.

Explanation

(B) The rapidly progressive dementia in this case is characteristic of Creutzfeldt-Jakob disease (CJD). The dementia is usually accompanied by motor dysfunction and abnormal EEG activity, as described in the question stem. The pathological hallmark of this disease is spongiforrn change in the gray matter. Death usually occurs within 6-12 months of disease onset.
At autopsy, the cerebellum in CJD appears atrophic, not hyperplastic.
Multiple lacunar infarcts are seen with vascular dementia, and patients typically present with focal neurological signs. Additionally, vascular dementia typically presents with a more gradual decline in cognitive function, measured in years rather than months.
Negri bodies are pathognornic for rabies, which does not cause dementia.
Neurofibrillary tangles are often seen in patients with Alzheimer's disease. Alzheimer's disease primarily affects the higher order association cortex; motor dysfunction is not generally observed. Additionally, in Alzheimer's disease, there is a more gradual decline in cognitive function, measured in years rather than months.

15. A 12-year-old male is investigated for severe headache and is found to have an intraventricular mass by CT scan. The mass is well demarcated with pushing borders. Microscopically, the excised mass shows cells with nuclei showing open chromatin with an inconspicuous nucleus and, well-defined cytoplasm with tapering processes. These cells are arranged in rosette like rests and around the vessels forming pseudorosettes. Also seen are epithelial lined tubules. The delicate processes are positive with PTAH staining and are positive for GFAP. What is the most likely diagnosis in this case?

Medullobalstoma

Neuroblastoma

Cerebellar astrocytoma

Ependymoma

Oligodendroglioma

MEDULLOBLASTOMA is the most frequently encountered intracranial neuroectoclermal tumor in children. Microscopically, medulloblastoma reveals a primitive small-celled malignant tumor forming Homer-Wright rosettes. The nuclei are closely packed, hyperchromatic, relatively uniform and round, oval, or carrot shaped. Dissemination through the CSF is a common complication. The tumor is highly malignant. However, the tumor is very radiosensitive. With total excision and radiation, the 5-year survival rate is as high as 75%.
NEUROBLASTOMA is one of the common solid tumors of childhood and can arise from adrenals or extra-adrenal sites. Cerebellar neuroblastomas are rare, and they arise in the early part of the first decade and show a highly aggressive clinical behavior. The majority are supratentorial, massive, and multicystic. Histologically, they are highly cellular, showing cells that are small with hyperchromatic nuclei and are arranged in solid sheets. A slightly fibrillated matrix traversed by delicate neurites is characteristic. They are negative for GFAP and do not stain with PTAH indicating the absence of glial component. Characteristic Homer-Wright rosettes with tumor cells at the periphery and young nerve fibrils at the center may be present.
CEREBELLAR ASTROCYTOMA predominantly occurs in children. They are characterized by a biphasic pattern. There are bipolar fibrillated and elongated cells packed in bundles with perivascular arrangements and there are stellate cells with short processes with a lacy pattern and show microcystic changes. Also seen are Rosenthal fibers, granular hyaline deposits, and eosinophilic intracytoplasmic bodies. These tumors grow slowly and have a benign course.
OLIGODENDROGLIONNAS constitute about 5 to 15% of gliomas and are most common in the fourth and fifth decades. The lesions are found in cerebral hemispheres, with a predilection for the white matter. Grossly, they are well- circumscribed, gelatinous, often with cyst formation, areas of hemorrhage and calcification. Microscopically, they are characterized by round cells with a small darkly staining nucleus, clear cytoplasm, and clearly defined cell membrane. In general, they have a better prognosis than astrocytomas.
EPENDYNNONNAS most often arise next to the ependyma lined ventricular system. They commonly occur near the 4th ventricle in the first 2 decades and in spinal cord in adults. Microscopically, they are characterized by ependymal rosettes, which are duct-like structures with a round or elongated central lumen around which columnar cells are arranged concentrically with basal nuclei.

Explanation

MEDULLOBLASTOMA is the most frequently encountered intracranial neuroectoclermal tumor in children. Microscopically, medulloblastoma reveals a primitive small-celled malignant tumor forming Homer-Wright rosettes. The nuclei are closely packed, hyperchromatic, relatively uniform and round, oval, or carrot shaped. Dissemination through the CSF is a common complication. The tumor is highly malignant. However, the tumor is very radiosensitive. With total excision and radiation, the 5-year survival rate is as high as 75%.
NEUROBLASTOMA is one of the common solid tumors of childhood and can arise from adrenals or extra-adrenal sites. Cerebellar neuroblastomas are rare, and they arise in the early part of the first decade and show a highly aggressive clinical behavior. The majority are supratentorial, massive, and multicystic. Histologically, they are highly cellular, showing cells that are small with hyperchromatic nuclei and are arranged in solid sheets. A slightly fibrillated matrix traversed by delicate neurites is characteristic. They are negative for GFAP and do not stain with PTAH indicating the absence of glial component. Characteristic Homer-Wright rosettes with tumor cells at the periphery and young nerve fibrils at the center may be present.
CEREBELLAR ASTROCYTOMA predominantly occurs in children. They are characterized by a biphasic pattern. There are bipolar fibrillated and elongated cells packed in bundles with perivascular arrangements and there are stellate cells with short processes with a lacy pattern and show microcystic changes. Also seen are Rosenthal fibers, granular hyaline deposits, and eosinophilic intracytoplasmic bodies. These tumors grow slowly and have a benign course.
OLIGODENDROGLIONNAS constitute about 5 to 15% of gliomas and are most common in the fourth and fifth decades. The lesions are found in cerebral hemispheres, with a predilection for the white matter. Grossly, they are well- circumscribed, gelatinous, often with cyst formation, areas of hemorrhage and calcification. Microscopically, they are characterized by round cells with a small darkly staining nucleus, clear cytoplasm, and clearly defined cell membrane. In general, they have a better prognosis than astrocytomas.
EPENDYNNONNAS most often arise next to the ependyma lined ventricular system. They commonly occur near the 4th ventricle in the first 2 decades and in spinal cord in adults. Microscopically, they are characterized by ependymal rosettes, which are duct-like structures with a round or elongated central lumen around which columnar cells are arranged concentrically with basal nuclei.

16. A 25-year-old white female at 20 weeks gestation with her first pregnancy presents to the physician for a routine visit without any complaints. The patient has no known co- morbidities and denies significant family medical problems. The patient has been compliant with all of her prenatal obstetrical appointments. The patient's vitals are as follows: pulse 68, respirations 12, blood pressure 102/68, and temperature is 98.6°F. A screening ultrasound examination of her infant is performed at this time and demonstrates an infant with hypoplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle, and enlargement of the posterior fossa. Question: What is the most likely diagnosis?

Chiari II Malformation

Alobar Holoprosencephaly

Dandy Walker Malformation

Hydranencephaly

Aqueductal Stenosis

Dandy-Walker Malformation is characterized by agenesis or hypoplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle, and enlargement of the posterior fossa. Over 700/0 of these patients have associated hydrocephalus, which usually develops postnatally.
Chiari II Malformation is a complex congenital malformation of the brain, nearly always associated with a nnyelomeningocele, that is characterized by downward displacement of the medulla, fourth ventricle, and cerebellum into the cervical spinal canal. Elongation of the pons and fourth ventricle due to a relatively small posterior fossa are also commonly seen.
Alobar holoprosencephaly is the most severe form of the holoprosencephalic defects, which reflect abnormal &vision of the embryonic forebrain. This form of holoprosencephaly consists of a single brain ventricle (monoventricle) without any formation of an interhemispheric fissure (i.e., fused cerebral hemispheres). The falx cerebri, corpus callosum, septum pellucidum, and fornix are absent, and the thalami are fused.
Hydrancephaly is a rare brain malformation in which there is near total absence of cerebral hemispheres and cerebral cortex. It is felt to result from an intra-uterine insult involving the internal carotid arteries bilaterally, and it is associated with a poor prognosis.
Aqueductal stenosis is the most common cause of congenital non-communicating, obstructive hydrocephalus in the newborn. Thinning and stretching of the cortical mantle may be seen as a result of ventricular dilation, which helps to differentiate this condition from hydrancephaly, a condition that lacks a cortical mantle or supratentorial brain formation.

Explanation

Dandy-Walker Malformation is characterized by agenesis or hypoplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle, and enlargement of the posterior fossa. Over 700/0 of these patients have associated hydrocephalus, which usually develops postnatally.
Chiari II Malformation is a complex congenital malformation of the brain, nearly always associated with a nnyelomeningocele, that is characterized by downward displacement of the medulla, fourth ventricle, and cerebellum into the cervical spinal canal. Elongation of the pons and fourth ventricle due to a relatively small posterior fossa are also commonly seen.
Alobar holoprosencephaly is the most severe form of the holoprosencephalic defects, which reflect abnormal &vision of the embryonic forebrain. This form of holoprosencephaly consists of a single brain ventricle (monoventricle) without any formation of an interhemispheric fissure (i.e., fused cerebral hemispheres). The falx cerebri, corpus callosum, septum pellucidum, and fornix are absent, and the thalami are fused.
Hydrancephaly is a rare brain malformation in which there is near total absence of cerebral hemispheres and cerebral cortex. It is felt to result from an intra-uterine insult involving the internal carotid arteries bilaterally, and it is associated with a poor prognosis.
Aqueductal stenosis is the most common cause of congenital non-communicating, obstructive hydrocephalus in the newborn. Thinning and stretching of the cortical mantle may be seen as a result of ventricular dilation, which helps to differentiate this condition from hydrancephaly, a condition that lacks a cortical mantle or supratentorial brain formation.

17. A 32-year-old mother of two children has 6-month history of annenorrhea, galactorrhea, and loss of libido. Her history is otherwise unremarkable and her b-hCG titer is undectable. The MOST likely cause of her symptoms is which of the following?

Adenoma of acidophils

Infarct in the pars nervosa

Head trauma

Adenoma of basophils

Adenoma of chromophobes

This woman has symptoms of hyperprolactinemia, caused by an adenoma of the lactotroph (an aciclophil). Lactotrophs (mammotrophs) have large, acidophilic granules, a few RER cisternae, and a Goigi apparatus near the nucleus. Lactotrophs are usually found as single cells in the adenohypophysis. In males and nonpregnant females, they are small round or polygonal cells. In lactating females, these cells become much more prominent, due to an expansion of the RER and Golgi apparatus. About 30% of all diagnosed pituitary adenomas are prolactinornas. Physiological hyperprolactinemia occurs during pregnancy, but this has been ruled out by the low B-hCG titer. Head trauma could possibly lead to abnormalities in pituitary function, but this possibility is ruled out by the lack of a history of head trauma.

Explanation

This woman has symptoms of hyperprolactinemia, caused by an adenoma of the lactotroph (an aciclophil). Lactotrophs (mammotrophs) have large, acidophilic granules, a few RER cisternae, and a Goigi apparatus near the nucleus. Lactotrophs are usually found as single cells in the adenohypophysis. In males and nonpregnant females, they are small round or polygonal cells. In lactating females, these cells become much more prominent, due to an expansion of the RER and Golgi apparatus. About 30% of all diagnosed pituitary adenomas are prolactinornas. Physiological hyperprolactinemia occurs during pregnancy, but this has been ruled out by the low B-hCG titer. Head trauma could possibly lead to abnormalities in pituitary function, but this possibility is ruled out by the lack of a history of head trauma.

18. A 42-year-old woman has a 2-month history of palpitations, tremors, and insomnia. During this time, she lost 5 pounds and noticed increased nervousness. On physical exam, she has a pulse of 125 bpm, blood pressure of 130/95 mmHg, and tremors. Her right thyroid lobe is enlarged with a 2 cm nodule. Laboratory evaluation shows free T4 of 2.7 ng/dL (normal range 0.7-1.6 ng/dL), free T3 of 601 pg/ml (normal 240-420 pg/ml), and undetectable TSH of <0.01 mIU/ml (0.5-4.5 mIU/ml). A radioiodine scan of the thyroid shows a focal area of intense uptake in the right lobe with suppression of the rest of the gland. What is the most likely diagnosis?

Hashimoto thyroiditis

Graves disease

Toxic multinodular goiter

Solitary toxic adenoma

Thyrotoxicosis factitia

The clinical presentation and laboratory evaluation of this patient suggest the diagnosis of hyperthyroidism secondary to solitary toxic adenoma, which is confirmed by a restricted area of iodine uptake in the right thyroid lobe with suppression of the rest of the gland.
Solitary toxic adenomas
are autonomic nodules that produce thyroid hormone independently of TSH control. They usually evolve from a single cell with a somatic mutation that confers autonomy (TSH-Independence), and as cells multiply, larger amounts of thyroid hormone are produced until hyperthyroidism becomes clinically evident. The diagnosis is suspected when a single nodule is palpable in an otherwise normal thyroid gland in a patient with hyperthyroidism. Diagnosis is confirmed by the finding of a focal area of iodine uptake with varying degrees of suppression of the
rest of the gland. Treatment is directed towards normalization of thyroid hormones by radioiodine treatment, or less frequently, by surgery.
Graves disease
is an autoimmune disorder in which excessive amounts of thyroid hormone are produced due to a constant activation of the TSH receptor in the thyroid cells by stimulating antibodies. Patients present with signs and symptoms of hyperthyroidism (nervousness, irritability, weight loss, tremor, palpitations) and increased diffuse iodine uptake by the gland on radioiodine scanning. Antithyroid antibodies are positive in most patients. Amongst the 3 therapeutic options available to treat Graves disease (antithyroid drugs, radiolodine, surgery), radioiodine is the most preferred in the United States.
Hashimoto thyroiditis
is an autoimmune disease in which diffuse infiltration of lymphocytes is observed in the thyroid, along with some areas of fibrosis. Patients present with varying degrees of hypothyroidism. With time, fibrosis becomes more extensive and the gland becomes atrophic. Occasionally, patients with Hashimoto thyroiditis present with hyperthyroidism in the beginning of the process, when extensive cell damage releases large amounts of thyroid hormone in the circulation. The diagnosis is suggested by a decreased, irregular uptake on radioiodine scan, elevated TSH levels, and positive thyroid antibodies. Replacement with levothyroxine is the treatment for hypothyroidism.
Toxic multinodular goiter
is a condition that affects mostly individuals above 50 years of age, and is a result of areas of autonomy developing in a rnultinodular goiter. Patients present with varying degrees of hyperthyroidism (subclinical and overt) and on radioiodine scan, the thyroid gland is increased in size, with areas of focal increased uptake. The treatment of choice is radioiodine, although surgery is also performed in cases of large, retrosternal goiters.
Thyrotoxicosis factitia
is a condition seen after ingestion of large amounts of thyroid hormone, mainly in psychiatric patients and in individuals who ingest weight loss preparations containing thyroid hormone. Signs and symptoms are similar to those found in patients with endogenous hyperthyroidism. TSH levels are undetectable and free T4 and T3 are elevated. There is absence of radiolodine uptake on scanning and thyroglobulin levels are low, suggesting suppressed endogenous production of thyroid hormones. Severely symptomatic patients may be treated with beta-blockers while the excessive amount of hormones is cleared from the body.

Explanation

The clinical presentation and laboratory evaluation of this patient suggest the diagnosis of hyperthyroidism secondary to solitary toxic adenoma, which is confirmed by a restricted area of iodine uptake in the right thyroid lobe with suppression of the rest of the gland.
Solitary toxic adenomas
are autonomic nodules that produce thyroid hormone independently of TSH control. They usually evolve from a single cell with a somatic mutation that confers autonomy (TSH-Independence), and as cells multiply, larger amounts of thyroid hormone are produced until hyperthyroidism becomes clinically evident. The diagnosis is suspected when a single nodule is palpable in an otherwise normal thyroid gland in a patient with hyperthyroidism. Diagnosis is confirmed by the finding of a focal area of iodine uptake with varying degrees of suppression of the
rest of the gland. Treatment is directed towards normalization of thyroid hormones by radioiodine treatment, or less frequently, by surgery.
Graves disease
is an autoimmune disorder in which excessive amounts of thyroid hormone are produced due to a constant activation of the TSH receptor in the thyroid cells by stimulating antibodies. Patients present with signs and symptoms of hyperthyroidism (nervousness, irritability, weight loss, tremor, palpitations) and increased diffuse iodine uptake by the gland on radioiodine scanning. Antithyroid antibodies are positive in most patients. Amongst the 3 therapeutic options available to treat Graves disease (antithyroid drugs, radiolodine, surgery), radioiodine is the most preferred in the United States.
Hashimoto thyroiditis
is an autoimmune disease in which diffuse infiltration of lymphocytes is observed in the thyroid, along with some areas of fibrosis. Patients present with varying degrees of hypothyroidism. With time, fibrosis becomes more extensive and the gland becomes atrophic. Occasionally, patients with Hashimoto thyroiditis present with hyperthyroidism in the beginning of the process, when extensive cell damage releases large amounts of thyroid hormone in the circulation. The diagnosis is suggested by a decreased, irregular uptake on radioiodine scan, elevated TSH levels, and positive thyroid antibodies. Replacement with levothyroxine is the treatment for hypothyroidism.
Toxic multinodular goiter
is a condition that affects mostly individuals above 50 years of age, and is a result of areas of autonomy developing in a rnultinodular goiter. Patients present with varying degrees of hyperthyroidism (subclinical and overt) and on radioiodine scan, the thyroid gland is increased in size, with areas of focal increased uptake. The treatment of choice is radioiodine, although surgery is also performed in cases of large, retrosternal goiters.
Thyrotoxicosis factitia
is a condition seen after ingestion of large amounts of thyroid hormone, mainly in psychiatric patients and in individuals who ingest weight loss preparations containing thyroid hormone. Signs and symptoms are similar to those found in patients with endogenous hyperthyroidism. TSH levels are undetectable and free T4 and T3 are elevated. There is absence of radiolodine uptake on scanning and thyroglobulin levels are low, suggesting suppressed endogenous production of thyroid hormones. Severely symptomatic patients may be treated with beta-blockers while the excessive amount of hormones is cleared from the body.

19. A 30-year-old woman sees her doctor because of depression. Upon questioning for the medical history, she denies any significant past medical history or surgeries. On physical examination, she is found to be obese. Her weight is localized to her trunk; her arms and legs are relatively normal. Her abdomen has prominent purple striae. Her face is very round and covered with acne. Her blood pressure is found to be 164/102 mmHg. Her laboratory results are as follows:

TEST	RESULTS	"REFERENCE "RANGE
BUN	14 mg/dL	7 - 18 mg/dL
Calcium	9.6 mg/dL	8.4-10.2 mg/dL
Potassium	4.1 mEq/L	3.5-5.0 mEq/L
Sodium	139 mEq/L	135-145 mEq/L

Further work-up is done and she is found to have a pituitary adenoma. Which of the following is most likely?

Addison's Disease

Conn's Syndrome

Cushing syndrome

Cushing's disease

Nelson's syndrome

This patient has a pituitary adenoma that is secreting ACTH. Cushing's disease refers to excessive secretion of ACTH by the pituitary. A pituitary adenoma is the most common cause for pituitary hypersecretion of ACTH. The increase in ACTH secretion results in hyperplasia of the adrenal cortex and a subsequent increase in glucocorticoid release. Characteristics of glucocorticoid excess include depression, truncal obesity, purple striae, round face (moon fades), and hypertension.
A distinction exists between Cushing's disease and Cushing's syndrome. Cushing's disease refers specifically to excessive secretion of ACTH by the pituitary. In Cushing's disease, the excessive ACTH secretion by the pituitary results in an increase in glucocorticoid release by the adrenal glands. Cushing's syndrome refers to the effects of excessive glucocorticoids, other than due to pituitary cause. Thus, Cushing's syndrome is due to excessive glucocorticoids. There will be hypertension with both Cushing's disease and Cushing's syndrome.
Addison's disease is primary adrenal insufficiency. The most common cause of Addison's disease is autoinnmunity. Tuberculosis is another cause of Addison's disease. The symptoms seen with Addison's disease include weight loss, lethargy, hyperpigmentation, nausea, and vomiting. Hypotension can be seen. Hyponatremia and hyperkalemia can be seen because of the lack of mineralocorticoicls. When there is decreased stimulation of the adrenal cortex due to a decrease in ACTH, it is called secondary adrenal insufficiency.
Conn's syndrome is due to excessive mineralocorticoids. Conn's syndrome is usually due to an adenoma that is secreting the aldosterone. Conn's syndrome results in hypernatrennia and hypokalennia. There is an associated hydrogen loss as well. There will be hypertension.
Nelson's syndrome is seen in patients who have bilateral adrenalectomy for Cushingrs disease. There is the subsequent development or progression of an ACTH secreting pituitary tumor.

Explanation

This patient has a pituitary adenoma that is secreting ACTH. Cushing's disease refers to excessive secretion of ACTH by the pituitary. A pituitary adenoma is the most common cause for pituitary hypersecretion of ACTH. The increase in ACTH secretion results in hyperplasia of the adrenal cortex and a subsequent increase in glucocorticoid release. Characteristics of glucocorticoid excess include depression, truncal obesity, purple striae, round face (moon fades), and hypertension.
A distinction exists between Cushing's disease and Cushing's syndrome. Cushing's disease refers specifically to excessive secretion of ACTH by the pituitary. In Cushing's disease, the excessive ACTH secretion by the pituitary results in an increase in glucocorticoid release by the adrenal glands. Cushing's syndrome refers to the effects of excessive glucocorticoids, other than due to pituitary cause. Thus, Cushing's syndrome is due to excessive glucocorticoids. There will be hypertension with both Cushing's disease and Cushing's syndrome.
Addison's disease is primary adrenal insufficiency. The most common cause of Addison's disease is autoinnmunity. Tuberculosis is another cause of Addison's disease. The symptoms seen with Addison's disease include weight loss, lethargy, hyperpigmentation, nausea, and vomiting. Hypotension can be seen. Hyponatremia and hyperkalemia can be seen because of the lack of mineralocorticoicls. When there is decreased stimulation of the adrenal cortex due to a decrease in ACTH, it is called secondary adrenal insufficiency.
Conn's syndrome is due to excessive mineralocorticoids. Conn's syndrome is usually due to an adenoma that is secreting the aldosterone. Conn's syndrome results in hypernatrennia and hypokalennia. There is an associated hydrogen loss as well. There will be hypertension.
Nelson's syndrome is seen in patients who have bilateral adrenalectomy for Cushingrs disease. There is the subsequent development or progression of an ACTH secreting pituitary tumor.

20. A 39-year-old, nulliparous, gravida 0 was referred for subfertility treatment and assisted conception. After appropriate investigations and counseling, she underwent in vitro fertilization. Following protocol regimens, 7 oocytes were recovered, of which 3 were fertilized normally. Transcervical embryo transfer was carried out on the third day following oocyte recovery. The blastomeres were normal: equal in size and shape with no fragmentation. A pregnancy test was carried out on a urine sample on day 17 and was positive. On 25^thday of gestation embryo died. Only one endocrine gland was found in embryo. What endocrine organ was most likely found?

Pineal gland

Thyroid gland

Parathyroid gland

Adrenal gland

Pancreas

The thyroid gland is the first of the body's endocrine glands to develop; it develops on approximately the 24th day of gestation. The gland originates as a proliferation of endodermal epithelial cells on the median surface of the developing pharyngeal floor.
Parathyroid glands begin differentiating at gestational weeks 5-6.
Pineal gland develops in week 10. It appears as a diverticulunn in the diencephalic roof of the third ventricle. However, melatonin cycle is not present on birth; it starts between 49 to 55 post-conception weeks.
The adrenal glands begin development during the fifth gestational week.
The pancreas begins development during the fifth week from dorsal and ventral outgrowths of endoderm that are a part of future duodenum.

Explanation

The thyroid gland is the first of the body's endocrine glands to develop; it develops on approximately the 24th day of gestation. The gland originates as a proliferation of endodermal epithelial cells on the median surface of the developing pharyngeal floor.
Parathyroid glands begin differentiating at gestational weeks 5-6.
Pineal gland develops in week 10. It appears as a diverticulunn in the diencephalic roof of the third ventricle. However, melatonin cycle is not present on birth; it starts between 49 to 55 post-conception weeks.
The adrenal glands begin development during the fifth gestational week.
The pancreas begins development during the fifth week from dorsal and ventral outgrowths of endoderm that are a part of future duodenum.

21. A 60-year-old male is concerned because he recently noticed a significant decrease in muscle mass and increase in his waist size, despite the fact that he changed neither his diet nor his life style. Both physical examination and laboratory results (including fasting glucose, TSH, and T4) are within normal limits. Question: What could explain those changes?

Growth hormone deficiency

Diabetes mellitus type II

Hypothyroidism

Paraneoplastic syndrome

Hypothalamus-pituitary-thyroid disturbance

A part of aging-related changes is a decrease in the secretion of the growth hormone. It causes a decrease in the muscle mass and an increase in the storage of fat.
Increasing age can be related to the development of Type II diabetes, but would be reflected in his laboratory results.
A decrease in the secretion of the thyroid hormones, which would lead to a decrease in the metabolic rate, should be demonstrated both by clinical presentation and laboratory values.
Paraneoplastic syndrome can take many forms, but is unlikely in a patient with normal physical and laboratory findings.
Although aging can be associated with an altered hypothalamus-pituitary-thyroid function, this is not the case in a patient with normal physical examination and laboratory results.

Explanation

A part of aging-related changes is a decrease in the secretion of the growth hormone. It causes a decrease in the muscle mass and an increase in the storage of fat.
Increasing age can be related to the development of Type II diabetes, but would be reflected in his laboratory results.
A decrease in the secretion of the thyroid hormones, which would lead to a decrease in the metabolic rate, should be demonstrated both by clinical presentation and laboratory values.
Paraneoplastic syndrome can take many forms, but is unlikely in a patient with normal physical and laboratory findings.
Although aging can be associated with an altered hypothalamus-pituitary-thyroid function, this is not the case in a patient with normal physical examination and laboratory results.

22. A 49-year-old patient is evaluated for suicidal ideation after he is found laying on train tracks by police. The man is disheveled and malodorous and states that he has "reached the end" and would rather die. He admits to depressed mood, anhedonia, poor energy, and appetite; he feels miserable and regrets what he has done with his life and wants to put an end to it. He states he has felt this way since age 26, after he was discharged from the military. The man indicates that his life was "great" until he increased his drinking, which caused a divorce at age 30. He has had 2 arrests for driving under the influence. He was in jail for 6 months after he had an accident while drunk that resulted in public property damage. He remembers that he initially felt sick in jail, with sweating, vomiting, shaking, and he experienced a seizure. He then improved after a few days and felt better during the rest of his imprisonment without any depression. Question: What criteria most strongly suggests alcohol abuse?

Desire to cut down

Recurrent drunk driving

Seizure after withdrawal

Suicidal ideation

Tolerance

The DSM criteria for alcohol abuse are recurrent use resulting in failure to fulfill obligations, recurrent use in hazardous situations, recurrent legal problems related to use, and continued use despite negative consequences. It is also important to note that the patient has never met the criteria for dependence.
A persistent desire or unsuccessful efforts to cut down is also a symptom of dependence.
Seizures are a symptom of severe withdrawal in chronic alcoholics. When the patient develops withdrawal symptoms and tolerance, requiring larger amount to achieve the desired effect, he or she has met the criteria for dependence.
Suicidal ideation in this patient is a consequence of his depression, which in turn, is secondary to alcohol use. Continued use of a substance despite knowledge of persistent or recurrent physical or psychological problems is also a criterion for dependence.
Tolerance is defined as the need to increase substance use to achieve the desired effect, or as diminished effect with continuous use of the same amount. Tolerance is a major criterion of dependence.

Explanation

The DSM criteria for alcohol abuse are recurrent use resulting in failure to fulfill obligations, recurrent use in hazardous situations, recurrent legal problems related to use, and continued use despite negative consequences. It is also important to note that the patient has never met the criteria for dependence.
A persistent desire or unsuccessful efforts to cut down is also a symptom of dependence.
Seizures are a symptom of severe withdrawal in chronic alcoholics. When the patient develops withdrawal symptoms and tolerance, requiring larger amount to achieve the desired effect, he or she has met the criteria for dependence.
Suicidal ideation in this patient is a consequence of his depression, which in turn, is secondary to alcohol use. Continued use of a substance despite knowledge of persistent or recurrent physical or psychological problems is also a criterion for dependence.
Tolerance is defined as the need to increase substance use to achieve the desired effect, or as diminished effect with continuous use of the same amount. Tolerance is a major criterion of dependence.

23. A 65-year-old otherwise healthy male reports that his feet are cold to the touch and his skin often gets a purplish color. Recently his hands become more sensitive to pain as the temperature decreases. Physical examination is within normal limits for the age. His laboratory tests, including TSH and T4, are within normal limits Question: What might be the cause of the intolerance to cold in this patient?

Hypothyroidism

Reduced end-organ response

Paraneoprastic syndrome

Hypothalamus-pituitary changes

Systemic vasculitis

Aging decreases the metabolism of thyroxine and its conversion to triiodothyronine. However, clinically significant alterations of thyroid hormone levels do not occur. Changes in the end-organ response to thyroid hormones are the cause of your patient's clinical presentation.
A decrease in the secretion of the thyroid hormones, which will lead to a decrease in metabolic rate, should be demonstrated in thyroid hormone levels in the blood. However, those levels are normal in your patient.
Paraneoplastic syndrome can take many forms, but is unlikely in a patient with normal physical and laboratory findings.
Although aging can be associated with an altered TSH secretion, this is not the case in your patient. There are no signs of disturbed hypothalamus-hypophysis (thyroid) axis function.
Vasculitis will more likely present with ischemia or multiple organ involvement.

Explanation

Aging decreases the metabolism of thyroxine and its conversion to triiodothyronine. However, clinically significant alterations of thyroid hormone levels do not occur. Changes in the end-organ response to thyroid hormones are the cause of your patient's clinical presentation.
A decrease in the secretion of the thyroid hormones, which will lead to a decrease in metabolic rate, should be demonstrated in thyroid hormone levels in the blood. However, those levels are normal in your patient.
Paraneoplastic syndrome can take many forms, but is unlikely in a patient with normal physical and laboratory findings.
Although aging can be associated with an altered TSH secretion, this is not the case in your patient. There are no signs of disturbed hypothalamus-hypophysis (thyroid) axis function.
Vasculitis will more likely present with ischemia or multiple organ involvement.

24. A 64-year-old African American woman presents with complaints of shortness of breath and dry cough. These symptoms, per the patient's statement, had an insidious onset and have been present for the past few weeks. Her physical examination is unremarkable. Her pulse, BP and temperature are as follows: 80/min, 130/90 mm Hg and 98.9°F. The patient's lab results and lung biopsy are as follows

Question: The next step in the patient's management entails:

Nothing, the disease has a self-limited course and will regress spontaneously

Performing acid-fast and silver stains on the biopsy

Treat the patient with antifungal drugs

Treat the patient with anti-tuberculous drugs

Treat the patient with steroids and immunosuppressive drugs

The candidate in this case presents with respiratory symptoms. The clinician requested a chest X-ray to evaluate the patient's lung and mediastinum. The plain X-ray showed the presence of a midline hilar that obviously abuts the bronchi, therefore explaining the irritating dry cough. As for any mass lesion, a biopsy was done. The histologic section shown in the image shows hilar lymph node tissue with multiple granulomas composed of epithelioid histiocytes with occasional giant cells. The increased serum calcium is frequently encountered in granulomatous disease predominantly sarcoidosis.
The next step in the patient's management should entail evaluating the biopsy for mycobacteria and fungi. These organisms are also associated with granulonnatous disease in the lymph nodes and can present with the same symptoms such as the current patient. The acid-fast stain is performed on tissue sections to detect Mycobacterium tuberculosis, which is the etiologic agent of tuberculosis. The silver stain such as Gomori's methenannine silver is frequently used in the lab to detect fungal organisms in tissue sections.
The rationale behind performing these stains on the tissue sections is to rule out the possibility of an infectious granulomatous disease before treating with steroids, which is the therapy of choice in sarcaidosis. However steroids are contraindicated in infectious granulomatous diseases since it mil make the organisms flourish by suppressing the host's immune system. Once the etiology of the granulonnatous disease is unveiled, the treatment with the respective therapeutic regimen can be initiated but not before that. Although some cases of sarcoidosis regress spontaneously, once the disease becomes symptomatic it should be treated. In addition, there are no criteria to aid in identifying the cases that will regress spontaneously versus those that will progress.

Explanation

The candidate in this case presents with respiratory symptoms. The clinician requested a chest X-ray to evaluate the patient's lung and mediastinum. The plain X-ray showed the presence of a midline hilar that obviously abuts the bronchi, therefore explaining the irritating dry cough. As for any mass lesion, a biopsy was done. The histologic section shown in the image shows hilar lymph node tissue with multiple granulomas composed of epithelioid histiocytes with occasional giant cells. The increased serum calcium is frequently encountered in granulomatous disease predominantly sarcoidosis.
The next step in the patient's management should entail evaluating the biopsy for mycobacteria and fungi. These organisms are also associated with granulonnatous disease in the lymph nodes and can present with the same symptoms such as the current patient. The acid-fast stain is performed on tissue sections to detect Mycobacterium tuberculosis, which is the etiologic agent of tuberculosis. The silver stain such as Gomori's methenannine silver is frequently used in the lab to detect fungal organisms in tissue sections.
The rationale behind performing these stains on the tissue sections is to rule out the possibility of an infectious granulomatous disease before treating with steroids, which is the therapy of choice in sarcaidosis. However steroids are contraindicated in infectious granulomatous diseases since it mil make the organisms flourish by suppressing the host's immune system. Once the etiology of the granulonnatous disease is unveiled, the treatment with the respective therapeutic regimen can be initiated but not before that. Although some cases of sarcoidosis regress spontaneously, once the disease becomes symptomatic it should be treated. In addition, there are no criteria to aid in identifying the cases that will regress spontaneously versus those that will progress.

25. A 15-year-old boy has suffered head trauma in a motor vehicle accident. His Glasgow coma scale (GCS) score is 7. Cranial CT scan shows multiple depressed fractures and intraparenchymal bleed. He has signs of raised intracranial pressure, manifesting as bradycarclia, hypertension, and irregular respiration. Question: What is the initial therapeutic intervention of choice for reducing the intracranial pressure in the above patient?

I.V mannitol

I.V. Furosemide

I.V. Dexamethasone

Hyperventilation

Hypothermia

As the patient has had severe head trauma and has a GCS score of 7 with irregular respirations. The initial therapeutic intervention of choice for reducing the intracranial pressure requires mechanical ventilation. Hypercarbia causes cerebral vasodilatation with increased cerebral blood flow, leading to increased intracranial pressure. Hyperventilation in order to maintain PaCO2 30-35 mmHg is helpful, as it reduces cerebral blood flow through cerebral vasoconstriction, thus reducing intracranial pressure. It is important to monitor the blood gases to ensure adequate oxygenation. PaCO2 of less than 25 mmHg should be avoided, as it may cause cerebral ischemia. Keeping the patient's head in rnidline and elevated 30 degrees allows optimal venous drainage and is further helpful in reducing intracranial pressure.
Intravenous mannitol 20% is an osmotic diuretic and promotes a shift of fluid from the intracellular to the intravascular compartment. In brain injury, irreversible cytotoxic edema occurs due to direct cell injury. Mannitol is less beneficial in the presence of severe disruption of blood brain barrier, as it may enter the central nervous system and draw fluid into the brain, causing exacerbation of cerebral edema. It can produce renal failure and hemolysis, as it creates a very hyperosmolar state. Other side effects include hypovolernia, hypotension, and electrolyte imbalance.
Furosemide is a strong diuretic and can be combined with osmotic diuretics for management of cerebral edema. It is a safer, but less effective, alternative.
Intravenous dexamethasone is not indicated when there is diffuse cerebral injury. It is of benefit when the edema is localized around an intracranial mass, e.g., an abscess or tumor. Corticosteroids have an anti- inflammatory and membrane-stabilizing effect and may be helpful in the management of vasogenic edema associated with mass lesions. Vasogenic edema results when increased permeability of the capillary endothelial cells permits fluid to escape into the extracellular space, but neurones are not primarily injured.
Hypothermia decreases cerebral metabolism and may reduce cerebral blood flow and intracranial pressure. Hypothermia can be achieved by using whole body cooling to a goal core temperature of 32-34 degree Celsius. Mild to moderate cooling has shown a small but significant decrease in mortality and neurological morbidity and an increased risk of pneumonia. Rewarnning should be accomplished in less than 24 hours. However, trials of hypothermia in children with traumatic brain injury showed no improvement in neurological outcome and mortality rates. Rather, mortality was increased in controlled hypothermia group.

Explanation

As the patient has had severe head trauma and has a GCS score of 7 with irregular respirations. The initial therapeutic intervention of choice for reducing the intracranial pressure requires mechanical ventilation. Hypercarbia causes cerebral vasodilatation with increased cerebral blood flow, leading to increased intracranial pressure. Hyperventilation in order to maintain PaCO2 30-35 mmHg is helpful, as it reduces cerebral blood flow through cerebral vasoconstriction, thus reducing intracranial pressure. It is important to monitor the blood gases to ensure adequate oxygenation. PaCO2 of less than 25 mmHg should be avoided, as it may cause cerebral ischemia. Keeping the patient's head in rnidline and elevated 30 degrees allows optimal venous drainage and is further helpful in reducing intracranial pressure.
Intravenous mannitol 20% is an osmotic diuretic and promotes a shift of fluid from the intracellular to the intravascular compartment. In brain injury, irreversible cytotoxic edema occurs due to direct cell injury. Mannitol is less beneficial in the presence of severe disruption of blood brain barrier, as it may enter the central nervous system and draw fluid into the brain, causing exacerbation of cerebral edema. It can produce renal failure and hemolysis, as it creates a very hyperosmolar state. Other side effects include hypovolernia, hypotension, and electrolyte imbalance.
Furosemide is a strong diuretic and can be combined with osmotic diuretics for management of cerebral edema. It is a safer, but less effective, alternative.
Intravenous dexamethasone is not indicated when there is diffuse cerebral injury. It is of benefit when the edema is localized around an intracranial mass, e.g., an abscess or tumor. Corticosteroids have an anti- inflammatory and membrane-stabilizing effect and may be helpful in the management of vasogenic edema associated with mass lesions. Vasogenic edema results when increased permeability of the capillary endothelial cells permits fluid to escape into the extracellular space, but neurones are not primarily injured.
Hypothermia decreases cerebral metabolism and may reduce cerebral blood flow and intracranial pressure. Hypothermia can be achieved by using whole body cooling to a goal core temperature of 32-34 degree Celsius. Mild to moderate cooling has shown a small but significant decrease in mortality and neurological morbidity and an increased risk of pneumonia. Rewarnning should be accomplished in less than 24 hours. However, trials of hypothermia in children with traumatic brain injury showed no improvement in neurological outcome and mortality rates. Rather, mortality was increased in controlled hypothermia group.