IgE-mediated reactions
Sensitivity to mackerel is quite common.
Mackerel may contain the parasite Anisakis simplex p4, and presumed sensitivity to mackerel may actually be an allergy to this parasite.
Other reactions
Members of the Scombroidae family easily form histamine at storage, ("scombroid poisoning").
This salt water fish, highly prized for its meat, approaches the shore in shoals in summer to spawn. The range is from the Mediterranean and Black Sea along Europe's west coast to the Arctic and down the American east coast. It occurs in dense schools just beneath the surface of the water. Catches suffer from huge size variations posing a puzzle for marine researchers and economic uncertainties for fishermen. Mackerel and other members of the family rapidly degrade and may, if improperly stored, contain large amounts of histamine associated with the bacterial enzyme histidine decarboxylase, which converts histidine to histamine. Mackerel and tuna reportedly cause intoxications referred to as scombroid poisoning (1).
Sensitivity to mackerel was seen in 20% of a group of cod-sensitive children (2). In a study of fish- and crustacea-allergic adults, the reactivity to mackerel was the second highest (3). The clinical sensitivity and specificity of Pharmacia CAP System™ f206 Mackerel was reported to be 86% and 90% respectively (4).
