[Scombroid poisoning after eating tuna fish]

On two separate occasions, a total of eight subjects ate tuna fish. Three out of four persons in the first case (a father aged 54, a mother aged 51 and a daughter aged 24 years) and one out of four persons in the second case (a 28-year-old woman) experienced erythema, respiratory distress and diarrhoea shortly after eating the fish. These symptoms are indicative of scombrotoxic fish poisoning. Histamine is produced in the muscle tissue of scombroid fish, such as tuna or mackerel, if it is kept at a temperature which is too high. Since the concentration of histamine is not evenly distributed through the fish's flesh, not everyone who eats the same fish will become ill to the same extent, and some may not even become ill at all. Furthermore, since the complaints are often mild and of short duration, most patients do not seek medical help, and probably few cases are officially reported. Despite the fact that sometimes only one person from a group of people eating the same fish becomes ill, and that the clinical complaints resemble an IgE-mediated allergic reaction, the illness is a food-borne intoxication with exogenous histamine. Therefore, patients can safely eat the same type of fish again.