Oral Pathology - Immunity

Immunodeficiency involves a decreased number or activity of lymphoid cells, leading to a weakened immune system. This condition can be congenital or acquired, and it makes individuals more susceptible to infections and diseases. Unlike autoimmunity, which is an overactive immune response against the body's own cells, immunodeficiency is characterized by a compromised immune system. Hypersensitivity refers to an exaggerated immune response, while immunization is the process of inducing immunity against a specific pathogen through vaccination.

During an anaphylactic type of hypersensitivity reaction, plasma cells produce an antibody called IgE. IgE antibodies are involved in allergic reactions and bind to specific receptors on mast cells and basophils. When the allergen reenters the body, it binds to the IgE antibodies on these cells, triggering the release of histamine and other chemicals that cause inflammation and allergic symptoms. This explanation highlights the role of IgE antibodies in the immune response during anaphylactic hypersensitivity reactions.

T cells are a type of lymphocyte that mature in the thymus. They are responsible for producing lymphokines, which are signaling molecules that help regulate the immune response. T cells can both increase and suppress the humoral immune response, depending on the specific situation. B cells, plasma cells, and macrophages are also important components of the immune system, but they do not have the same role as T cells in terms of maturing in the thymus and producing lymphokines.

Immunization with a vaccine works by producing active acquired immunity. This means that the vaccine stimulates the immune system to produce an immune response, including the production of antibodies, against a specific antigen. This helps the body recognize and fight off the antigen if it is encountered in the future, providing protection against the disease it causes.

The correct answer is "titer" because it refers to the measurement of a specific antibody level in the blood. Titer is a quantitative measurement that determines the concentration of antibodies present in a sample. It is commonly used in diagnostic tests to assess the immune response to a particular infection or vaccination. Titer levels can indicate the strength of an immune response and help in determining the effectiveness of treatments or vaccines.

Opportunistic infections occur when normally harmless microorganisms in the body, such as the normal oral flora, cause disease in individuals with weakened immune systems or other predisposing factors. These infections take advantage of the weakened immune system to cause illness. Therefore, when normal oral flora can cause disease, it is classified as an opportunistic infection.

Lupus erythematosus is a pathologic condition that occurs more frequently in females. A blood test is important for diagnosis, indicating its significance in identifying the condition. In addition to oral lesions that are ulcerated, lupus erythematosus also presents with a characteristic butterfly-shaped lesion on the skin. This information aligns with the given statement, making lupus erythematosus the correct answer.

Oral candidiasis, also known as oral thrush, is a fungal infection caused by the overgrowth of a type of fungus called Candida. Candida is a normal inhabitant of the mouth, but certain factors such as weakened immune system, poor oral hygiene, or the use of certain medications can lead to its overgrowth and the development of oral candidiasis. This condition is characterized by creamy white lesions on the tongue, inner cheeks, or roof of the mouth. Treatment typically involves antifungal medications to eliminate the fungus and restore oral health.

Antibodies, also known as immunoglobulins, are proteins that are an essential component of the immune system. They are produced by lymphocytes, a type of white blood cell, in response to the presence of foreign substances in the body. Antibodies play a crucial role in identifying and neutralizing these foreign substances, such as bacteria or viruses, by binding to them and marking them for destruction by other immune cells. Therefore, the correct answer is "also termed immunoglobins" as it accurately describes the alternative name for antibodies.

Xerostomia refers to the condition of having a dry mouth, which is the most significant oral manifestation of Sjogren's syndrome. Sjogren's syndrome is an autoimmune disorder that primarily affects the salivary glands, causing reduced saliva production. This can lead to various oral symptoms, including dryness, difficulty in swallowing and speaking, increased risk of dental decay and oral infections. Therefore, xerostomia is the correct answer as it accurately represents the main oral manifestation associated with Sjogren's syndrome.

The humoral immune response involves the production of antibodies. Antibodies are proteins produced by B cells in response to the presence of antigens. These antigens can be foreign substances such as bacteria or viruses. Antibodies bind to antigens and help in their neutralization or destruction. They can also activate other components of the immune system to eliminate the antigens. Therefore, antibodies play a crucial role in the humoral immune response by specifically targeting and eliminating foreign substances in the body.

Desquamative gingivitis is a condition characterized by inflammation and peeling of the gums. It can be seen in various autoimmune diseases such as cicatricial pemphigoid, pemphigus vulgaris, and lichen planus. In cicatricial pemphigoid, the immune system attacks the skin and mucous membranes, including the gums. Pemphigus vulgaris is another autoimmune disorder that causes blistering of the skin and mucous membranes, including the gums. Lichen planus is a chronic inflammatory condition that can affect the skin, mucous membranes, and gums. Therefore, all of the above conditions can present with desquamative gingivitis.

In an autoimmune disease, the cells of the body are no longer tolerated by the immune system and are treated as antigens. This means that the immune system mistakenly identifies the body's own cells as foreign and launches an immune response against them. This can lead to inflammation and damage to various organs and tissues in the body. Hypersensitivity refers to an exaggerated immune response to an allergen, immunodeficiency is a weakened immune system, and hyperplasia refers to abnormal cell growth.

Hypersensitivity reactions refer to exaggerated immune responses to certain substances. Lichen planus is not considered a hypersensitivity reaction but rather an inflammatory skin condition. Urticaria, angioedema, and contact mucositosis are all examples of hypersensitivity reactions.

The immune system defends the body against foreign substances called antigens. Antigens are molecules or particles that can stimulate an immune response, leading to the production of antibodies. These antibodies are produced by plasma cells, which are a type of lymphocyte. Therefore, while plasma cells and antibodies are involved in the immune response, they are not the substances that the immune system defends against. The immune system recognizes and targets antigens to protect the body from potential harm.

The memory function of the immune system allows for faster future immune responses. This is because the immune system retains memory of the antibody, which means that it can recognize and respond more quickly to a previously encountered antigen. This memory allows the immune system to mount a more efficient and effective immune response, leading to faster clearance of pathogens and a stronger defense against future infections.

Reiter's syndrome is an immunologic disorder. This condition is characterized by inflammation in various parts of the body, including the joints, eyes, and urinary tract. It is believed to be triggered by an infection, typically a bacterial infection in the gastrointestinal or urogenital tract. The immune system's response to the infection leads to the development of Reiter's syndrome. It can affect both men and women, but it is more commonly observed in men.

Tzanck cells are seen in pemphigus vulgaris. Tzanck cells are multinucleated giant cells that are formed due to the fusion of keratinocytes in the skin. They are typically found in the blister fluid or in the base of the vesicles in pemphigus vulgaris. Pemphigus vulgaris is an autoimmune blistering disorder that affects the skin and mucous membranes. It is characterized by the formation of intraepidermal blisters and the presence of autoantibodies against desmoglein 3, a protein involved in cell adhesion.

Histocytosis X is not associated with aphthous ulcers. Aphthous ulcers are recurrent painful sores that can occur in the mouth, and they are commonly seen in conditions such as Behcet syndrome, ulcerative colitis, and Crohn's disease. However, there is no known association between histocytosis X and aphthous ulcers.

Angioedema is a condition characterized by swelling beneath the skin, typically in the face and throat. The epiglottis is a flap of tissue located at the base of the tongue that covers the windpipe during swallowing, preventing food and liquid from entering the airway. If angioedema occurs in the epiglottis, it can cause severe swelling and potentially block the airway, leading to difficulty breathing and potentially life-threatening complications. Therefore, angioedema in the epiglottis can create very serious complications for the patient.

The plaque-like form of lichen planus can simulate hyperkeratosis or leukoplakia. This form is characterized by the presence of flat-topped, shiny, reddish-purple papules that may merge together to form larger plaques. These plaques can appear white due to hyperkeratosis, which is an excessive thickening of the outer layer of the skin. This similarity in appearance can make it difficult to distinguish between lichen planus and hyperkeratosis or leukoplakia.

Erythema multiforme is associated with the appearance of a "target lesion" on the skin. This skin condition is characterized by the presence of distinctive concentric rings of color, giving the lesion a target-like appearance. Behcet syndrome, systemic lupus erythematosus, and lichen planus do not typically present with this specific target lesion. Therefore, erythema multiforme is the most likely disease associated with the given description.

The statement "the secondary lesion of syphilis occurs at the site of inoculation with the organism" is false. In syphilis, the primary lesion is called a chancre, which occurs at the site of infection. The secondary lesions of syphilis, on the other hand, are systemic and can appear on various parts of the body, not just at the site of inoculation. The tertiary lesion of syphilis is called a gumma, which is a granulomatous lesion that can affect multiple organs. Syphilis is indeed caused by the spirochete Treponema pallidum.

Type 2 hypersensitivity reactions involve activated complement. In these reactions, IgG or IgM antibodies bind to antigens on the surface of cells, leading to activation of the complement system. This activation results in the recruitment of immune cells and the destruction of the target cells through various mechanisms, such as complement-mediated lysis or antibody-dependent cell-mediated cytotoxicity. Examples of type 2 hypersensitivity reactions include autoimmune hemolytic anemia, transfusion reactions, and some drug allergies.

Eosinophilic granuloma is the most benign type of histiocytosis X disease. This condition is characterized by the abnormal proliferation of a type of white blood cell called histiocytes. Eosinophilic granuloma typically affects children and young adults, causing bone lesions that can lead to pain and swelling. However, it generally has a good prognosis and does not usually spread to other organs. Hand-Schuller-Christian disease and Letterer-Siwe disease are more severe forms of histiocytosis X, while chronic disseminated reticulosis is a different condition altogether.

The most distinct and definitive characteristic that distinguishes pemphigus from pemphigoid is the histologic findings. Histologic findings refer to the examination of tissue samples under a microscope to identify specific cellular changes or patterns. In pemphigus, the histologic findings typically show acantholysis, which is the loss of intercellular connections between skin cells. In pemphigoid, the histologic findings usually show subepidermal blistering, which is the separation of the top layer of the skin from the underlying layers. These histologic findings are crucial in accurately diagnosing and differentiating between pemphigus and pemphigoid.

Erythematous candidiasis is usually not completely asymptomatic. This condition, also known as acute atrophic candidiasis or "red tongue", is characterized by red patches on the tongue and oral mucosa. It can cause discomfort, pain, and a burning sensation in the affected areas. Therefore, the statement that erythematous candidiasis is usually completely asymptomatic is false.

Following a needlestick accident, dental personnel may immediately receive acquired passive immunity. This type of immunity occurs when pre-formed antibodies are transferred from one individual to another. In this case, the dental personnel may receive antibodies through a medical intervention, such as receiving immune globulin or specific antibodies, to provide immediate protection against any potential pathogens that may have been introduced through the needlestick accident. This acquired passive immunity is temporary and does not provide long-term protection.

Herpes zoster, commonly known as shingles, is a viral infection that causes a painful rash. One of the characteristic clinical features of herpes zoster is the unilateral distribution of lesions. This means that the rash and blisters caused by the virus typically appear on only one side of the body, following the path of a specific nerve. This pattern of distribution helps differentiate herpes zoster from other skin conditions that may cause similar symptoms.

In Reiter's syndrome, the oral lesion may resemble geographic tongue. Geographic tongue is a benign condition characterized by irregular, map-like patches on the surface of the tongue. These patches are caused by the loss of papillae, giving the tongue a smooth appearance in certain areas. This condition is typically asymptomatic and does not require treatment. In Reiter's syndrome, the oral lesion may appear similar to geographic tongue due to inflammation and the presence of irregular patches on the tongue. However, it is important to note that Reiter's syndrome is a systemic condition that affects multiple organs, whereas geographic tongue is a localized oral condition.

Natural Killer (NK) cells are a type of lymphocyte that plays a crucial role in the innate immune response. Unlike adaptive immune cells, such as B and T cells, NK cells do not possess memory. This means that NK cells do not retain information about previous encounters with specific antigens. Instead, they rely on their ability to recognize and eliminate infected or abnormal cells through a process called "target cell killing". Therefore, the statement "NK cells do not have memory" is true.

Hand-Schuller-Christian disease is a form of Langerhans cell disease that is characterized by a triad of symptoms. This triad includes exophthalmos (protrusion of the eyeballs), diabetes insipidus (excessive thirst and urination), and osteolytic lesions (destruction of bone tissue). This disease primarily affects children and is caused by the proliferation of Langerhans cells, a type of immune cell, in various organs of the body.

Herpangina is not associated with the Epstein-Barr virus. Herpangina is a viral infection caused by the Coxsackie virus or other enteroviruses, not the Epstein-Barr virus. It is characterized by small, painful ulcers or sores that develop in the back of the throat. On the other hand, hairy leukoplakia, nasopharyngeal carcinoma, and infectious mononucleosis are all conditions that can be associated with the Epstein-Barr virus.

B lymphocytes (B cells) are a vital part of the adaptive immune system. They are responsible for producing antibodies that specifically target pathogens, including those found in the oral cavity. These antibodies can neutralize bacteria, viruses, and other foreign substances, preventing infection and maintaining oral health. Osteoblasts and fibroblasts are involved in bone formation and connective tissue production, respectively, while erythrocytes are red blood cells responsible for oxygen transport.

The correct answer is eosinophils and mononuclear cells. Langerhans cell disease is a rare disorder characterized by the abnormal accumulation of Langerhans cells, a type of immune cell, in various tissues. These cells are histologically characterized by the presence of eosinophils, which are a type of white blood cell involved in allergic reactions and immune responses, and mononuclear cells, which are a type of immune cell with a single nucleus. These two cell types are commonly seen in Langerhans cell disease and can help distinguish it from other conditions.

The correct answer is "is caused by a human papilloma virus." Verruca vulgaris, also known as a common wart, is caused by the human papilloma virus (HPV). It is a contagious skin infection that commonly appears on the hands and fingers, but can also occur on other parts of the body. Clinically, verruca vulgaris can resemble an irritative fibroma, but the underlying cause is the HPV infection. It is not necessarily most commonly seen on the buccal mucosa, as it can occur on any skin surface.

The statement "skin lesions are common in cicatrical pemphigoid" is false. Cicatricial pemphigoid, also known as mucous membrane pemphigoid, primarily affects mucous membranes such as the mouth, eyes, nose, throat, and genitals. It typically does not involve the skin. Skin involvement is more commonly seen in other forms of pemphigoid, such as bullous pemphigoid.

Macrophages are immune cells that play a crucial role in the immune response. They can be activated by lymphokines, which are signaling molecules released by other immune cells. Activation of macrophages by lymphokines enhances their ability to engulf and destroy pathogens, produce inflammatory mediators, and present antigens to other immune cells. This activation is important for the coordination and regulation of the immune response.

A cystologic smear can be helpful in diagnosing tuberculosis and syphilis because it allows for the examination of cells collected from the affected area. In tuberculosis, the smear can reveal acid-fast bacilli, which are characteristic of the disease. In syphilis, the smear can show the presence of Treponema pallidum, the bacterium responsible for the infection. By analyzing the cellular changes and identifying the causative organisms, a cystologic smear can aid in the accurate diagnosis of tuberculosis and syphilis.