Proper use of skin tests with food extracts in diagnosis of hypersensitivity to food in children.

This study was undertaken to determine the proper use of skin tests with food extracts in diagnosis of hypersensitivity to food in children. Cutaneous reactions evoked by graded amounts of food extracts were compared with results of double-blind food challenge and in vitro release of histamine from leucocytes. A 3 mm or greater weal reaction in skin tests by puncture technique using food extracts of 1:20 w/v concentration was found to indicate the degree of hypersensitivity likely to be associated with clinically significant hypersensitivity reactions to food. Proper use of this simple technique will facilitate accurate diagnosis of food hypersensitivity in children by identifying the group among whom all positive reactions to food challenges will be found. Nevertheless, double-blind food challenge is essential to establish a diagnosis of symptomatic hypersensitivity to food.