An individual with a known bee sting allergy experiences anaphylaxis after being stung. Which mechanism explains why localized mast cell degranulation rapidly leads to systemic vasodilation and bronchoconstriction?

💡 Explanation

Crosslinking of IgE receptors on mast cells by bee venom allergens initiates degranulation, releasing histamine and other mediators. Because this occurs throughout the body rather than being limited to the sting site, therefore widespread vasodilation and bronchoconstriction occur, rather than just localized inflammation.

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