The clinical evaluation should be supported by the CAP RAST test performed at a laboratory on a small blood sample. In the case of a negative CAP RAST test result, a skin test with extracts of the suspected seafood species can give additional information. In Southern Africa we have many seafood species which are not found in Europe or the United States. This can mean that commercial tests are not available. Therefore, we at UCT Allergology Unit have improved the diagnostic process by developing and using in-house RAST tests and Western Blot tests and skin tests with locally important seafood allergens.
Patients have to know that seafood allergies tend to persist for several or more years.
Avoid any possible direct or indirect exposure to the offending seafood species including handling or inhaling cooking vapours. Wear a Medic Alert badge and very sensitised patients should also carry an injectable adrenaline syringe. There are numerous laboratory tests for allergy to different species of Fish, Crustacea and Molluscs. No all of these tests are commonly encountered in South Africa, as these species are not often consumed as food. However, tehre is an increasing trend in South Africa towards the use of unusual species of seafoods in restaurants, as well as visits by South Africans overseas where they will be exposed to these other seafood species.