Squid hypersensitivity: a clinical and immunologic study.

Hypersensitivity to mollusk has rarely been described in the literature. Among the mollusks, the cephalopods are a group of great importance as a food source. We report seven patients who had had symptoms highly suggestive of IgE-mediated reactions after ingesting squid or inhaling vapors from cooking squid. All had previously suffered from persistent rhinitis or asthma for years. In addition, six of the seven patients had had symptoms after ingesting shrimp. Skin prick tests were strongly positive for boiled squid extract and for various commercial crustacean extracts. Specific IgE antibodies against boiled extract and several crustacean extracts were demonstrated in all patients by RAST and reverse enzyme immunoassay. Cross reactivity between squid and shrimp and other crustaceans was demonstrated by reverse immunoassay inhibition studies. Cross reactivity could not be demonstrated between squid and octopus, which are both cephalopods, nor between squid and other mollusks.