Scombroid poisoning: mini-review with case histories.

Scombroid poisoning has become an almost world-wide medical problem. It is probably the most common cause of fish poisoning, although frequently misdiagnosed as "Salmonella infection'. While there remains some question as to the definitive etiology, there is little doubt that the poisoning is caused by the ingestion of certain mackerel-like fishes whose tissues have undergone a number of changes provoked by bacteria, and involving the conversion of histidine to histamine, potentiated by diamines. Improper storage of the fishes, usually at temperatures above 20 degrees C, appears to be the most important predisposing factor. The organisms most commonly involved are Proteus sp., Clostridium sp., Escherichia sp., Salmonella sp. and Shigella sp. Twenty-five cases of scombroid poisoning are presented. The clinical manifestations were very similar in most cases, consisting of: alterations in taste; anxiety; hyperemia, particularly of the face and neck; nausea; pruritus; headache; certain other symptoms and signs. Most patients responded to antihistamitics, and all cases were self-limiting.