RAST in the diagnosis of hypersensitivity to horse allergens. A comparison with clinical history and in vivo tests.

Case history, skin tests and RAST were compared in a group (n = 40) of children with a history suggesting allergy to horses and in a group (n = 43) in whom there was no suspicion of hypersensitivity to horses. There was an agreement of 91% between case history and prick test. The same magnitude of agreement was found between case history and RAST (89%), and the agreement between RAST and prick test was 90%. The results of this investigation are clearly in contrast to earlier earlier reports, in that there was a very good correlation between prick test, RAST and case history. The results suggest that: (a) a proper evaluation of the skin test is of critical importance for the degree of correlation with other diagnostic tests; and (b) RAST is as reliable as carefully performed and evaluated skin tests.