MILK ALLERGY

Abstract

Skin testing separately and with equal concentrations of the purified milk proteins, casein, alpha-lactalbumin, beta-lactoglobulin, and BSA was done in 85 milk allergic children. For control purposes, intradermal tests with the same antigens were done in 102 normal children and 31 children allergic to non-milk substances. Six per cent of the normal children had weakly positive reactions. However, positive skin tests occurred in 68% of the children allergic, but not to milk, and in 59% of the children allergic to milk. In the milk allergic children, the incidence of positive reactions to each milk protein was similar. The incidence of positive skin tests in milk allergic children was higher than previously apprised. Positive skin tests in the milk allergic child were obtained long after the dietary elimination of milk antigens and after the disappearance of circulating milk antibodies as detected by a variety of techniques. In contrast to the control groups, strongly positive skin tests occurred only in milk allergic patients. Although no correlation was found between the results of all skin tests and the results of oral challenges with the same milk protein, a close correlation was found between the results of strongly positive skin tests and the results of oral challenge with the same milk protein. It appears that weakly positive skin tests with purified milk proteins have a little diagnostic value, but strongly positive skin tests have diagnostic significance.