What is the primary cause of anaphylaxis?

Correct Answer: B

Rationale: The correct answer is B: Systemic release of vasoactive mediators. Anaphylaxis is a severe allergic reaction that is primarily caused by the systemic release of vasoactive mediators such as histamine, prostaglandins, and leukotrienes from mast cells and basophils. These mediators lead to widespread vasodilation, increased vascular permeability, bronchoconstriction, and systemic hypotension, resulting in the characteristic symptoms of anaphylaxis. Choice A (Immune complex deposition) is incorrect because anaphylaxis is not caused by the deposition of immune complexes but rather by the immediate hypersensitivity reaction. Choice C (Localized mast cell degranulation) is incorrect because anaphylaxis involves systemic mast cell degranulation leading to widespread effects throughout the body, not just localized reactions. Choice D (T cell activation) is incorrect because anaphylaxis is primarily mediated by IgE antibodies and mast cells, not T cells.

Correct Answer: B

Rationale: The correct answer is B: Epinephrine. Epinephrine is the first-line treatment for anaphylaxis as it rapidly reverses the symptoms by constricting blood vessels, relaxing airway muscles, and increasing heart rate. It is crucial in preventing severe complications and can be life-saving. Antihistamines (choice A) only target histamine effects, which are not sufficient in managing anaphylaxis. Corticosteroids (choice C) are used as adjunct therapy but are not as immediate or critical as epinephrine. Antibiotics (choice D) are not indicated for anaphylaxis treatment. Therefore, epinephrine is the most appropriate choice for managing anaphylaxis effectively.

Correct Answer: C

Rationale: The correct answer is C: Inform the client not to drive or sign legal papers for 24 hours. This is because belimumab can cause dizziness and fatigue as side effects, which may impair the client's ability to drive or make important decisions. It is crucial for the nurse to ensure the safety of the client and others by advising against these activities for 24 hours post-administration. Choice A: Observing the client for at least 2 hours is important for monitoring immediate adverse reactions, but it is not the most appropriate action in this scenario. Choice B: Instructing the client about the monthly infusion schedule is important for treatment adherence, but it is not the most immediate concern after the first dose administration. Choice D: Ensuring emergency equipment is working and nearby is important for safety precautions, but advising the client not to drive or sign legal papers is more directly related to the potential side effects of belimumab.

Correct Answer: D

Rationale: The correct answer is D: IFN-γ. CD4+ TH1 cells are known to primarily produce interferon-gamma (IFN-γ). This cytokine plays a crucial role in promoting cell-mediated immunity and enhancing the activity of macrophages. IL-4 (choice A) is produced by CD4+ TH2 cells and promotes humoral immunity. IL-10 (choice B) is an anti-inflammatory cytokine produced by various immune cells. IL-5 (choice C) is predominantly produced by CD4+ TH2 cells and is involved in eosinophil activation. Therefore, the main cytokine produced by CD4+ TH1 cells is IFN-γ, making choice D the correct answer.

Correct Answer: E

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.