Question

Anaphylaxis is an example of

• A. Type I hypersensitivity
• B. Type II hypersensitivity
• C. Type III hypersensitivity
• D. Type IV hypersensitivity

Hint:

Types of hypersensitivity: \[ \boxed{ \begin{aligned} \text{Type I} &\rightarrow \text{IgE-mediated (Allergy, Anaphylaxis)} \text{Type II} &\rightarrow \text{Antibody-mediated cytotoxicity} \text{Type III} &\rightarrow \text{Immune complex-mediated} \text{Type IV} &\rightarrow \text{Delayed, T-cell mediated} \end{aligned} } \]

Answer 1

The Correct Option is A

Step 1: Recall anaphylaxis. Anaphylaxis is a rapid, severe allergic reaction mediated by IgE antibodies. Upon re-exposure to an allergen, IgE bound to mast cells triggers the release of histamine and other inflammatory mediators.

Step 2: Identify the type of hypersensitivity. Since it is an immediate IgE-mediated reaction, \[ \boxed{\text{Anaphylaxis is a Type I hypersensitivity reaction}.} \] Therefore, \[ \boxed{(A)} \] is the correct answer.