Quiz About Diseases: Trivia Exam!

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  • 1/20 Questions

    A 40-year-old woman presents at a local health center with complaints of having paroxysmal attacks of chills, fever, and sweating. These attacks last for a day or two and are repeated at intervals. The examination of a stained blood specimen reveals ring-like and crescent-shaped forms within the erythrocytes. What is the most probable causative agent?

    • Dracunculus medinensis
    • Trypanosoma gambiense
    • Plasmodium falciparum
    • Wuchereria bancrofti
    • Schistosoma mansoni
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About This Quiz


What do you know about diseases? A disease is an ailment of the living animal or plant body or one of its parts that weakens normal functions and is typically exhibited by distinguishing signs and symptoms. It means that you have an illness, and it is a harmful deviation from the usual physical or functional state of an organism. This quiz will reveal your knowledge of diseases.

Quiz About Diseases: Trivia Exam! - Quiz

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  • 2. 

    A 12-year-old boy is brought to the hospital with extreme fatigue and lethargy. Physical examination shows pallor. Subsequent investigations show the presence of an abdominal mass. Biopsy reveals a high-grade malignant tumor composed of lymphoid cells. The pathologist notes tumor cells being engulfed by macrophages imparting a “starry-sky appearance” to the biopsy. Which of the following viruses is associated with a patient’s clinical condition?

    • HPV

    • EBV

    • HBV

    • HTLV

    • CMV

    Correct Answer
    A. EBV
    Explanation
    The presence of an abdominal mass and the biopsy findings of a high-grade malignant tumor composed of lymphoid cells with a "starry-sky appearance" suggest a diagnosis of Burkitt lymphoma. Burkitt lymphoma is strongly associated with Epstein-Barr virus (EBV) infection. EBV is a DNA virus that is known to be involved in the pathogenesis of various lymphoproliferative disorders, including Burkitt lymphoma. Therefore, EBV is the most likely virus associated with this patient's clinical condition.

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  • 3. 
    Presented in the following figure is the natural progression of an HIV infection. Which event marks a critical turning point in the pathogenesis of AIDS?   - ProProfs

    Presented in the following figure is the natural progression of an HIV infection. Which event marks a critical turning point in the pathogenesis of AIDS?  

    • Emergence of CCR5-tropic virus strain

    • Emergence of CD8-tropic virus strain

    • Emergence of CD4-tropic virus strain

    • Emergence of CXCR4-tropic virus strain

    • Emergence of macrophage-tropic virus strain

    Correct Answer
    A. Emergence of CXCR4-tropic virus strain
    Explanation
    Binding. The replicative cycle begins when gp120 binds CD4+. Binding of gp120 with CD4+ induces a conformational change in CD4+, allowing CD4+ to recruit a chemokine receptor (co-receptor; CCR5 initially & CXCR4 inlater stages of the infection) in the vicinity of gp120, as well as bringing the viral envelope closer to the cell membrane. The gp120-CD4+-chemokine receptor complex then induces a conformational change in gp120, therefore exposing the fusionpeptide gp41

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  • 4. 

    A 60-year-male patient presents with an alteration in bowel habits. The stool for occult blood is positive. Colonoscopy shows an ulcerating mass in the colon, infiltrating the underlying muscle as well as lymph nodes. The tumor is resected and sent to the pathology laboratory, where its features are reported by the pathologist. Which of the following is the best prognostic indicator of survival in this patient?

    • Tumor stage

    • Degree of histologic differentiation

    • Degree of nuclear atypia

    • Nuclear-to-cytoplasmic ratio

    • Tumor necrosis

    Correct Answer
    A. Tumor stage
    Explanation
    The best prognostic indicator of survival in this patient is the tumor stage. Tumor stage refers to the extent of the cancer and whether it has spread to nearby lymph nodes or other parts of the body. It provides important information about the aggressiveness of the cancer and helps determine the appropriate treatment options. A higher tumor stage is generally associated with a poorer prognosis and lower survival rates. Therefore, knowing the tumor stage is crucial for predicting the patient's outcome and guiding their management.

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  • 5. 
    A 30-year-old man presented with a history of fatigue, dizziness, and persistent diarrhea. Upon questioning, it was found that he frequented a restaurant that specialized in raw seafood. He looked pale and laboratory investigations revealed the following: Characteristic parasite ova were found in the stool. What is the most probable etiologic agent?     - ProProfs

    A 30-year-old man presented with a history of fatigue, dizziness, and persistent diarrhea. Upon questioning, it was found that he frequented a restaurant that specialized in raw seafood. He looked pale and laboratory investigations revealed the following: Characteristic parasite ova were found in the stool. What is the most probable etiologic agent?    

    • Fasciola hepática

    • Diphyllobothrium latum

    • Blastocystis hominis

    • Clonorchis sinensis

    • Enteromonas intestinalis

    Correct Answer
    A. Diphyllobothrium latum
    Explanation
    The most probable etiologic agent in this case is Diphyllobothrium latum. This is because the patient presented with symptoms of fatigue, dizziness, and persistent diarrhea, which are commonly associated with Diphyllobothrium latum infection. Additionally, the fact that characteristic parasite ova were found in the stool further supports this diagnosis. Diphyllobothrium latum is a tapeworm that is commonly acquired through the consumption of raw or undercooked fish, making it likely that the patient contracted the infection from the restaurant that specialized in raw seafood.

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  • 6. 

    A 25-year-old pregnant woman with coronary artery stenosis was admitted to the care unit for placement of a coronary stent. Acute anticoagulation therapy was required and an appropriate drug was given (drugA).  After several days, the patient developed severe drug-induced thrombocytopenia and drugA was withdrawn. As parenteral anticoagulation therapy was still required, a second drug (drugB) was given which was a direct thrombin inhibitor which did not induce the formation of antiplatelet antibodies.  Which of the following paired drugs is most likely to be the chosen therapy?

    • Heparin and Lepirudin

    • W arfarin and aminocaproic acid

    • Alteplase and clopidogrel

    • Abciximab and thrombin

    • Warfarin and protamine sulphate

    Correct Answer
    A. Heparin and Lepirudin
    Explanation
    The correct answer is Heparin and Lepirudin. Heparin is a commonly used anticoagulant that can be used during pregnancy. However, in this case, the patient developed drug-induced thrombocytopenia, which is a known side effect of heparin. Therefore, heparin was withdrawn and Lepirudin, a direct thrombin inhibitor, was given as an alternative anticoagulant. Lepirudin does not induce the formation of antiplatelet antibodies, making it a suitable choice for this patient.

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  • 7. 

    A virus that encodes transforming proteins and a transmission comparable to HIV  is endemic in southern Japan, the Caribbean, and among African Americans in the southeastern United States. What are the transforming proteins of this virus and which cells or tissues are infected?

    • Tax and HBZ/ T cells

    • E6 and E7/ mucosal epithelia

    • LMP-1 and EBNA/ B cells

    • vIL-6/ B Cells

    • VSRC/ Avian embryo fibroblast

    Correct Answer
    A. Tax and HBZ/ T cells
    Explanation
    Human T-Leukemia viruses (HTLV) HTLV-1, -2 and -5 are associated with leukemias and lymphomas. HTLV-1 has been established as the causative agent of Human Adult Acute T-cell lymphocytic leukemia (ATLL) as well as a nervous system degenerative disorder: Tropical spastic paraparesis (HAM/TSP). HTLV-1 was isolated in 1980 from the cells of a patient with a cutaneous T-cell lymphoma. Transmission occurs primarily by sexual contact and by exchange of contaminated blood, e.g., in transfusions and intravenous drug use. Clusters of HTLV-associated disease are found in certain geographic areas (southern Japan, Melanesia, the Caribbean, Central and South America, and parts of Africa). Although less than 1% of people worldwide have HTLV-1 antibody, more than 10% of the population in endemic areas are seropositive, and antibody may be found in 50% of relatives of virus-positive leukemia patients. HTLV-viruses have a marked affinity for mature T cells with the viral promoter-enhancer sequences in the long terminal repeat may be responsive to signals associated with the activation and proliferation of T cells. The provirus is found in all leukemic cells of ATLL cases. HTLV-1 has no viral oncogene. Two special genes (in addition to the standard retroviral genes gag, pol, and env) called tax and hbz play a role in oncogenesis by regulating mRNA transcription and translation through transactivation. Transcriptional regulator protein tax causes activation of cellular interleukin-2 IL-2 (T- cell growth factor) and its receptor IL-2R. Stimulation of viral mRNA synthesis, and induction of NF-kB, leads to T cell growth increasing the likelihood that the cells will become malignant. ATLL is poorly responsive to therapy. The 5-year survival rate for patients with this cancer is < 5%.

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  • 8. 
    A 55-year-old male presents with weight loss and anorexia. Physical examination reveals left supra-clavicular lymphadenopathy. The physician suspects cancer and performs a lymph node biopsy. The biopsy is shown in the image below. Which of the following is the most likely primary tumor? - ProProfs

    A 55-year-old male presents with weight loss and anorexia. Physical examination reveals left supra-clavicular lymphadenopathy. The physician suspects cancer and performs a lymph node biopsy. The biopsy is shown in the image below. Which of the following is the most likely primary tumor?

    • Signet ring carcinoma of stomach

    • Squamous cell carcinoma of esophagus

    • Transitional cell carcinoma

    • Renal cell carcinoma

    • Malignant lymphoma

    Correct Answer
    A. Signet ring carcinoma of stomach
    Explanation
    The image shows a lymph node biopsy with signet ring cells. Signet ring cells are characteristic of signet ring carcinoma, which is most commonly found in the stomach. This is supported by the patient's presenting symptoms of weight loss and anorexia, as well as the presence of left supra-clavicular lymphadenopathy. Squamous cell carcinoma of the esophagus, transitional cell carcinoma, renal cell carcinoma, and malignant lymphoma are less likely to present with these specific findings.

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  • 9. 
    A 17-year-old male presents to his family physician with sore throat, fever, and tender cervical lymphadenopathy for over 3 days. Laboratory investigations show lymphocytic leukocytosis. Peripheral blood smear is shown below.  Test for heterophile antibodies is positive. Based on the information provided, which of the following potential complication is your most likely concern?   - ProProfs

    A 17-year-old male presents to his family physician with sore throat, fever, and tender cervical lymphadenopathy for over 3 days. Laboratory investigations show lymphocytic leukocytosis. Peripheral blood smear is shown below.  Test for heterophile antibodies is positive. Based on the information provided, which of the following potential complication is your most likely concern?  

    • Aplastic anemia

    • Blast crisis

    • Renal failure

    • Acute leukemia

    • Splenic rupture

    Correct Answer
    A. Splenic rupture
    Explanation
    The most likely concern in this case is splenic rupture. The patient's symptoms of sore throat, fever, and lymphadenopathy, along with the positive test for heterophile antibodies, are consistent with infectious mononucleosis. Splenic rupture is a potential complication of infectious mononucleosis, especially in young males. This can occur due to enlargement and inflammation of the spleen, which can lead to its rupture and cause severe abdominal pain and potentially life-threatening bleeding. Prompt diagnosis and management are important to prevent this complication.

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  • 10. 

    A 60-year-old male, a chronic smoker, presents with cough and hemoptysis. Physical examination shows hyperpigmentation of the skin, multiple bruises, and hypertension. Laboratory tests show high blood sugar levels. A chest x-ray reveals an irregular mass in the right lung field. Lung biopsy shows small cells with round to oval, deeply staining nuclei, rather a scant cytoplasm, and many mitoses. Electron microscopy shows neuro-secretory granules. Immunologic stains on light microscopy are positive for synaptophysin and S-100. Based on the information provided, which of the following substances produced by the lung tumor that is most likely responsible for the patient’s signs and symptoms?

    • ADH

    • ACTH

    • Serotonin

    • Erythropoietin

    • Calcium

    Correct Answer
    A. ACTH
    Explanation
    The patient's signs and symptoms, including hyperpigmentation of the skin, multiple bruises, hypertension, and high blood sugar levels, are consistent with Cushing's syndrome. This syndrome is caused by excessive production of cortisol, which is regulated by ACTH. The lung tumor in this patient is most likely a small cell lung carcinoma, which can produce ACTH and lead to Cushing's syndrome.

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  • 11. 
    A 22-year-old man has blood oozing from his nose and mouth. Physical examination shows petechiae and ecchymosis distributed over most of his body. There are generalized lymphadenopathy and hepato-splenomegaly. Laboratory studies show a moderately severe normocytic anemia, thrombocytopenia, and a WBC count of 32,000/mm3. The d-dimer blood test is increased and both the prothrombin and partial thromboplastin times are increased. The photograph shows the peripheral blood smear. What chromosome translocation is most likely to be present in this patient? - ProProfs

    A 22-year-old man has blood oozing from his nose and mouth. Physical examination shows petechiae and ecchymosis distributed over most of his body. There are generalized lymphadenopathy and hepato-splenomegaly. Laboratory studies show a moderately severe normocytic anemia, thrombocytopenia, and a WBC count of 32,000/mm3. The d-dimer blood test is increased and both the prothrombin and partial thromboplastin times are increased. The photograph shows the peripheral blood smear. What chromosome translocation is most likely to be present in this patient?

    • t(14;18)

    • T(9;22)

    • T(8;14)

    • T(11;14)

    • T(15;17)

    Correct Answer
    A. T(15;17)
    Explanation
    NOTICE THE "AURER RODS"
    Acute promyelocytic leukemia is a subtype of acute myelogenous leukemia (AML), a cancer of the blood and bone marrow. It is also known as acute progranulocytic leukemia; APL; AML with t(15;17)(q22;q12), PML-RARA and variants; FAB subtype M3 and M3 variant. In APL, there is an abnormal accumulation of immature granulocytes called promyelocytes. The disease is characterized by a chromosomal translocation involving the retinoic acid receptor alpha (RARα or RARA) gene and is unique from other forms of AML in its responsiveness to all trans retinoic acid (ATRA) therapy.

    Follicular lymphoma is the most common of the indolent non-Hodgkin's lymphomas, and the second-most-common form of non-Hodgkin's lymphomas overall.
    A translocation between chromosome 14 and 18 results in the overexpression of the bcl-2 gene. As the bcl-2 protein is normally involved in preventing apoptosis, cells with an overexpression of this protein are basically immortal. The bcl-2 gene is normally found on chromosome 18, & the translocation moves the gene near to the site of the immunoglobulin heavy chain enhancer element on chromosome 14.

    T(8;14) =Burkitts
    T(9;22) = CML

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  • 12. 

    A 46-year-old male doctor suffers a needle stick injury while conducting medical mission work in Western Africa.  Upon returning to the United States, the man is screened for communicable diseases and is found to be infected with HIV-2.  He is started on an appropriate HAART regimen.  Which of the following drugs would most likely be part of his HAART regimen?

    • Efavirenz

    • Tenofovir

    • Enfuvirtide

    • Maraviroc

    • Nevirapine

    Correct Answer
    A. Tenofovir
    Explanation
    ENTRY INHIBITORS:
    Enfuvirtide
    Only for HIV-1
    MOA: binds to Gp-41 of viral envelope and prevents conformation ∆ req. for fusion --> inhibits viral fusion
    AE --> Eosinophilia
    Maraviroc
    Viral: R5 HIV-1 (CCR5-tropic HIV-1)
    MOA: binds specifically to CCR5
    Uses: R5 HIV-1 infection (req. to be screen for R5)
    NNRTI’s:
    Allosteric (non-competitive) inhibition of RT
    Do not require phosphorylation to become active
    Met. by cyt. P-450
    Only effective in HIV-1

    Delaviridine
    Protein bound
    Contraindicated: pregnancy and p-450 drug
    Efavirenz
    Adverse: ↑ [cholesterol]
    Contraindicated: Prego (esp. 1st trim.)
    Nevirapine
    Used for prevention of transmission of HIV from mom to newborn (single-dose administration!)

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  • 13. 

    A 20-year-old man presents to the physician with pharyngitis, fever and lymphadenopathy indicative of an infection with a pathogen that produces heterophile antibodies. Which of the following is the most likely site of latency after the acute stage, and what type of viral products will be found?

    • T cell/ proteins

    • Oropharyngeal epithelial cells/proteins

    • Neurons/ proteins

    • B cells/ proteins

    • Neurons/ transcripts

    Correct Answer
    A. B cells/ proteins
    Explanation
    Infectious mononucleosis occurs with infection by the Epstein–Barr virus.
    The infection is spread via saliva, and has an incubation period of four to seven weeks. Symptoms usually persist for two to three weeks, but fatigue is often more prolonged.
    The length of time that an individual remains contagious is unclear, but may be the highest during the first six weeks following infection. Some studies indicate that a person can spread the infection for many months after symptoms are completely gone, with one particular study indicating as long as 18 months.
    The virus replicates first within epithelial cells in the pharynx (which causes pharyngitis, or sore throat), and later primarily within B cells (which are invaded via their CD21). The host immune response involves cytotoxic (CD8-positive) T cells against infected B lymphocytes, resulting in enlarged, atypical lymphocytes (Downey cells).

    When the infection is acute (recent onset, instead of chronic), HETEROPHILE ANTIBODIES are produced.
    Similar symptoms can be caused by cytomegalovirus, adenovirus, and Toxoplasma gondii, but will result in a NEGATIVE HETEROPHILE ANTIBODY TEST

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  • 14. 

    A 63-year-old woman was admitted to the hospital with a moderate acute rejection of her transplanted heart, which she received four months earlier.  Upon admission muromonab, CD3 was added to her immunosuppressant regimen.  Ten days later her rejection symptoms abated.  What is the immediate action of muromonab CD3 which counteracted rejection of the transplant?

    • Reduction in antigen-presenting cell numbers

    • Prevention of the synthesis of IL-1

    • Binding to antibodies which are attacking the transplant

    • Depletion of the available pool of activated T-cells

    • Binding to and inactivation of TNF-alpha

    Correct Answer
    A. Depletion of the available pool of activated T-cells
    Explanation
    Muromonab-CD3 is an immunosuppressant drug given to reduce acute rejection in patients with organ transplants. It is a monoclonal antibody targeted at the CD3 receptor, a membrane protein on the surface of T cells
    As it is of Mouse origing think of "migh-T-mouse"

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  • 15. 
    A 50-year-old woman comes to your office complaining of difficulty breathing and swallowing.  Physical examination reveals a thin woman who appears younger than her stated age with tachypnea and tachycardia.  Her anti-nuclear antibody staining pattern is shown. Which anti-nuclear antibody would most likely be positive in this patient? - ProProfs

    A 50-year-old woman comes to your office complaining of difficulty breathing and swallowing.  Physical examination reveals a thin woman who appears younger than her stated age with tachypnea and tachycardia.  Her anti-nuclear antibody staining pattern is shown. Which anti-nuclear antibody would most likely be positive in this patient?

    • Antibodies against double stranded DNA

    • Antibodies against DNA topoisomerase I

    • Antibodies against ribonucleoproteins

    • Antibodies against histones

    • Antibodies against centromeric proteins

    Correct Answer
    A. Antibodies against DNA topoisomerase I
  • 16. 

    Which one of the major classes of anti-malignant drugs kills cells whether they are in the G0 phase or progressing through the cell cycle?

    • Alkylating agents

    • Antimetabolites

    • Vinca alkaloids

    • Taxanes

    • Epidophyllotoxins

    Correct Answer
    A. Alkylating agents
    Explanation
    An alkylating antineoplastic agent is an alkylating agent used in cancer treatment that attaches an alkyl group (CnH2n+1) to DNA.[1] The alkyl group is attached to the guanine base of DNA, at the number 7 nitrogen atom of the purine ring. Since cancer cells, in general, proliferate faster and with less error-correcting than healthy cells, cancer cells are more sensitive to DNA damage — such as being alkylated. Alkylating agents are used to treat several cancers. However, they are also toxic to normal cells (cytotoxic), leading to damage, in particular in cells that divide frequently, as those in the gastrointestinal tract, bone marrow, testicles and ovaries, which can cause loss of fertility. Most of the alkylating agents are also carcinogenic. Hyperthermia is especially effective at enhancing the effects of alkylating agents. The following three groups are almost always considered "classical". Nitrogen mustards[7] Cyclophosphamide Mechlorethamine or mustine (HN2) (trade name Mustardgen) Uramustine or uracil mustard Melphalan Chlorambucil Ifosfamide Nitrosoureas Carmustine Lomustine Streptozocin Alkyl sulfonates Busulfan Thiotepa and its analogs are usually considered classical but can be considered nonclassical.

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  • 17. 

    A 20-year-old man presented to the hospital with complaints of chronic diarrhea, with mucus and blood present in the stool. Sigmoidoscopy revealed pseudo polyps and flask-shaped ulcers in the colon. A CT scan of the liver and the lung showed abscesses. What is the most probable diagnosis?

    • Amoebiasis

    • Hydatid disease

    • Giardiasis

    • Taeniasis

    • Cyclosporiasis

    Correct Answer
    A. Amoebiasis
    Explanation
    The most probable diagnosis in this case is amoebiasis. The patient's symptoms of chronic diarrhea, mucus, and blood in the stool, along with sigmoidoscopy findings of pseudo polyps and flask-shaped ulcers in the colon, are consistent with amoebic colitis. The presence of abscesses in the liver and lung on CT scan further supports the diagnosis, as amoebiasis can cause extra-intestinal manifestations such as liver and lung abscesses. Hydatid disease, giardiasis, taeniasis, and cyclosporiasis do not typically present with the same combination of symptoms and findings seen in this patient.

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  • 18. 
    The figure shows the metabolism of the anti-hypertensive drug debrisoquine to the inactive metabolite 4OH-debrisoquine in 258 unrelated British volunteers. Which statement about this experiment is false? - ProProfs

    The figure shows the metabolism of the anti-hypertensive drug debrisoquine to the inactive metabolite 4OH-debrisoquine in 258 unrelated British volunteers. Which statement about this experiment is false?

    • Patients in group A would get the lowest reduction of blood pressure from a given dose.

    • Patients in group C would be most at risk of getting an overdose

    • The drug is converted by a cytochrome P450.

    • The distribution is tri-modal

    • Patients in the left of the diagram metabolize the drug only very slowly.

    Correct Answer
    A. Patients in the left of the diagram metabolize the drug only very slowly.
    Explanation
    The statement "Patients in the left of the diagram metabolize the drug only very slowly" is false. The figure shows a tri-modal distribution, indicating that there are three distinct groups of patients with different rates of drug metabolism. Therefore, the patients in the left of the diagram do not metabolize the drug only very slowly, as there are other groups with even slower metabolism.

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  • 19. 

    A 31-year-old-man who recently returned from a visit to South America presents to the emergency department complaining of malaise, muscle pains, severe headaches, and fever. Two days earlier he had an abrupt onset of coldness and chills followed by high fever and headache, with nausea and vomiting.  A laboratory test showed erythrocytes highly parasitized by a protozoan identified as P.falciparum.  Which of the following drugs would be most appropriate for treating this patient?

    • Quinidine gluconate

    • Chloroquine

    • Primaquine phosphate

    • Mefloquine

    • Pyrimethamine

    Correct Answer
    A. Quinidine gluconate
    Explanation
    Quinidine gluconate would be the most appropriate drug for treating this patient because the symptoms and laboratory findings are consistent with a diagnosis of severe malaria caused by Plasmodium falciparum. Quinidine is an effective antimalarial drug that is commonly used for severe cases of malaria. It works by killing the malaria parasites in the blood and helping to control the symptoms of the infection. Other antimalarial drugs like chloroquine, primaquine phosphate, mefloquine, and pyrimethamine may be used for treating less severe cases or for prophylaxis, but for severe cases caused by P. falciparum, quinidine gluconate is the treatment of choice.

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  • 20. 

    An 18-month old with a history of recurrent bacterial and viral infections, failure to thrive, developmental delay, and tremors is submitted to your care. On exam, you notice a lack of peripheral lymphoid tissue. Blood analysis reveals lymphopenia with normal B cell count and normal immunoglobulin levels. The patient is most likely suffering from a deficiency in which enzyme?

    • Hypoxanthine guanine phosphoribosyl transferase (HGPRT)

    • Adenine phosphoribosyl transferase (APRT)

    • Adenosine desaminase (ADA)

    • Adenosine kinase

    • Purine nucleoside phosphorylase

    Correct Answer
    A. Purine nucleoside phosphorylase
    Explanation
    PNP-deficiency is a rare autosomal recessive metabolic disorder that results in severe combined immunodeficiency. PNP-deficiency is extremely rare. Only 33 patients with the disorder in the United States have been documented. In the United Kingdom, only one child has been diagnosed with this disorder For this reason, it will probably be on the STEP. The disorder is caused by a mutation of the purine nucleoside phosphorylase (PNP) gene, located at chromosome 14q13.1.[3][4] PNP is a key enzyme in the purine salvage pathway, and is required for purine degradation. Specifically, it catalyzes the conversion of inosine and guanosine to hypoxanthine. A deficiency of it leads to build up of elevated deoxy-GTP (dGTP) levels resulting in T-cell toxicity and deficiency.[4][5] In contrast to adenosine deaminase deficiency (another deficiency of purine metabolism), there is minimal disruption to B cells.[6] PNP deficiency is inherited in an autosomal recessive manner.[1] This means the defective gene responsible for the disorder is located on an autosome (chromosome 14 is an autosome), and two copies of the defective gene (one inherited from each parent) are required in order to be born with the disorder. The parents of an individual with an autosomal recessive disorder both carry one copy of the defective gene, but usually do not experience any signs or symptoms of the disorder.

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Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.

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  • Mar 20, 2023
    Quiz Edited by
    ProProfs Editorial Team
  • Jun 14, 2012
    Quiz Created by
    Chachelly

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