Scombroid food poisoning

Scombroid food poisoning, also known as simply scombroid, is a foodborne illness that typically results from eating spoiled fish. Symptoms may include flushed skin, sweating, headache, itchiness, blurred vision, abdominal cramps and diarrhea. Onset of symptoms is typically 10 to 60 minutes after eating and can last for up to two days. Rarely, breathing problems, difficulty swallowing, redness of the mouth, or an irregular heartbeat may occur.

Scombroid occurs from eating fish high in histamine due to inappropriate storage or processing. Fish commonly implicated include tuna, mackerel, mahi mahi, escolar, sardine, anchovy, bonito, herring, bluefish, amberjack, and marlin. These fish naturally have high levels of histidine, which is converted to histamine when bacterial growth occurs during improper storage. Subsequent cooking, smoking, or freezing does not eliminate the histamine. Diagnosis is typically based on the symptoms and may be supported by a normal blood tryptase. If a number of people who eat the same fish develop symptoms, the diagnosis is more likely.

Prevention is by refrigerating or freezing fish right after it is caught. Treatment is generally with antihistamines such as diphenhydramine and ranitidine. Epinephrine may be used for severe symptoms. Along with ciguatera fish poisoning, it is one of the most common type of seafood poisoning. It occurs globally in both temperate and tropical waters. Only one death has been reported. The condition was first described in 1799.