Systemic lupus erythematosus is an example of which type of hypersensitivity reaction?
Type IV
Type III
Type II
Type I
The Correct Answer is B
A. Type IV Hypersensitivity (Delayed Hypersensitivity Reaction): This type of reaction involves a delayed immune response, typically occurring 24 to 72 hours after exposure to an antigen. It's characterized by the activation of T cells and macrophages, leading to inflammation. This type of hypersensitivity is often associated with conditions like contact dermatitis and some autoimmune diseases.
B. Type III Hypersensitivity (Antibody-Mediated Reaction): Type III hypersensitivity reactions occur when immune complexes, which are composed of antigens and antibodies, deposit in various tissues. This leads to inflammation and tissue damage. Systemic lupus erythematosus (SLE) is an example of a disease associated with Type III hypersensitivity.
C. Type II Hypersensitivity: This type of reaction involves antibodies (IgG or IgM) targeting antigens on the surface of cells. This can lead to cell destruction through various mechanisms, such as complement activation or antibody-dependent cell-mediated cytotoxicity (ADCC). Examples include hemolytic transfusion reactions and autoimmune hemolytic anemia.
D. Type I Hypersensitivity (Immediate Hypersensitivity Reaction): Type I hypersensitivity is characterized by an immediate immune response, typically occurring within minutes of exposure to an allergen. It involves the release of histamines and other mediators from mast cells and basophils, leading to symptoms like hives, respiratory distress, and anaphylaxis. Allergies, like hay fever and food allergies, are examples of Type I hypersensitivity reactions.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is A
Explanation
A. Most type-1 reactions are allergic: This statement is accurate. Type-1 hypersensitivity reactions are typically associated with allergies. When a person is exposed to a specific allergen (like pollen or certain foods), their immune system overreacts, leading to various symptoms, from mild to severe.
B. It is mediated by IgA: This statement is incorrect. Type-1 hypersensitivity reactions are primarily mediated by immunoglobulin E (IgE) antibodies. When these antibodies bind to allergens, they trigger the release of histamine and other chemicals, causing allergic symptoms.
C. It never contributes to autoimmune diseases: This statement is incorrect. While type-1 hypersensitivity reactions are often associated with allergies, they are distinct from autoimmune diseases. In autoimmune diseases, the immune system mistakenly attacks the body's own cells and tissues, which is a different mechanism from hypersensitivity reactions.
D. Most occur against medications: This statement is not entirely accurate. While some type-1 hypersensitivity reactions can be triggered by medications (like penicillin), they can also be caused by various other allergens such as pollen, animal dander, insect venom, and certain foods. The prevalence of medication-induced type-1 reactions varies, and it's not accurate to say that most occur against medications.
Correct Answer is B
Explanation
A. IgD: Immunoglobulin D (IgD) is found on the surface of B cells and serves as a receptor for antigen recognition during the immune response. Its exact function is not fully understood, but it plays a role in the activation of B cells.
B. IgE: Immunoglobulin E (IgE) is primarily associated with allergic responses and defense against parasitic infections. When an allergen enters the body, IgE antibodies trigger the release of histamine and other chemicals, leading to allergy symptoms. IgE is also involved in protecting against certain parasites.
C. IgG: Immunoglobulin G (IgG) is the most abundant immunoglobulin in the bloodstream. It provides long-term immunity by recognizing and neutralizing pathogens such as bacteria and viruses. IgG antibodies are involved in secondary immune responses and are transferred from mother to fetus, providing passive immunity.
D. IgM: Immunoglobulin M (IgM) is the first antibody produced during an initial immune response to an antigen. It is effective at agglutination (clumping) of pathogens. IgM antibodies are generally found in blood and lymph fluid and are the first line of defense during infections.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today