COMBINED SKIN PRICK AND PATCH TESTING ENHANCES IDENTIFICATION OF FOODALLERGY IN INFANTS WITH ATOPIC-DERMATITIS

Background: Early recognition of dietary allergies in infants with ato pic dermatitis is essential for avoidance of unnecessary elimination d iets, amelioration of the skin disease, and secondary prevention of th e development of multiple food allergies. Simple and accurate methods of identifying provocative foods are urgently needed. Methods: The use fulness of skin prick and patch tests as indicators of cow milk allerg y was evaluated in 183 patients ranging in age from 2 to 36 months wit h double-blind placebo-controlled (n = 118) or open (n = 65) cow milk challenges. Results: The oral cow milk challenges were interpreted as positive in 54% of both challenge types. Positive challenge rapidly el icited pruritus, urticaria, and/or exanthema in 49% of cases and delay ed-onset eczematous lesions in 51%. The skin prick and parch tests gav e markedly discrepant results; prick tests were positive in 67% of the cases with acute-onset reactions to milk challenge, whereas parch res ts tended to be negative. Parch tests were positive in 89% of those wi th delayed-onset reactions, although prick rests were frequently negat ive. Conclusions: The observations indicate that IgE and T cell-mediat ed responses to cow milk can be distinguished in atopic dermatitis. Pa rallel skin testing with combined prick and patch tests can significan tly enhance the accuracy in diagnosis of specific dietary allergies in patients with atopic dermatitis.