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Anaphylaxis shock differential — RCPSC IM MCQ

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HardCritical CareAnaphylaxis shock differentialRCPSC IM

A 25-year-old woman develops hypotension, wheeze and urticaria minutes after receiving ceftriaxone. She is treated with intramuscular epinephrine, fluids and oxygen. Symptoms improve, but the team wants objective support for the diagnosis for later allergy assessment. What is the most appropriate investigation?

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Correct answer: B — Serum tryptase drawn within the acute window and again at baseline later

Anaphylaxis is a clinical diagnosis and epinephrine must not be delayed. Acute and baseline tryptase can support mast-cell activation and assist later specialist evaluation.

Reference: Canadian Society of Allergy and Clinical Immunology anaphylaxis guidance