Scombroid poisoning results from histamine formation due to bacterial histidine decarboxylase in decaying fish. Which description matches this mechanism?

Scombroid poisoning results from histamine formation due to bacterial histidine decarboxylase in decaying fish. Which description matches this mechanism?

• A. IgE-mediated reaction to shellfish
• B. Bacterial endotoxin causing fever
• C. Neurotoxin causing paralysis
• D. Histamine formation causing allergy-like symptoms after decaying fish

Answer: (D)

Histamine formation by bacterial histidine decarboxylase in decaying fish produces symptoms that mimic an allergic reaction, but without IgE involvement. Spoiled fish harbor bacteria that convert histidine to histamine; this histamine then acts on receptors in the skin, vessels, and gut, causing flushing, warmth, hives, headache, abdominal cramps, and sometimes diarrhea or bronchospasm. It looks like an allergy, yet it isn’t driven by IgE sensitization. This is different from an endotoxin fever or a neurotoxin that causes paralysis. The histamine is heat-stable and not destroyed by cooking, so symptoms can occur even after the fish is cooked. Prevention centers on proper refrigeration and avoiding spoiled fish; treatment typically involves antihistamines and supportive care.

Histamine formation by bacterial histidine decarboxylase in decaying fish produces symptoms that mimic an allergic reaction, but without IgE involvement. Spoiled fish harbor bacteria that convert histidine to histamine; this histamine then acts on receptors in the skin, vessels, and gut, causing flushing, warmth, hives, headache, abdominal cramps, and sometimes diarrhea or bronchospasm. It looks like an allergy, yet it isn’t driven by IgE sensitization. This is different from an endotoxin fever or a neurotoxin that causes paralysis. The histamine is heat-stable and not destroyed by cooking, so symptoms can occur even after the fish is cooked. Prevention centers on proper refrigeration and avoiding spoiled fish; treatment typically involves antihistamines and supportive care.