Acurácia do teste cutâneo de leitura tardia na alergia à proteína do leite de vaca com manifestações gastrointestinais

Abstract

Food allergy is an adverse reaction to food that occurs after ingestion with involvement of immunological mechanisms. The clinical manifestations of non-IgE-mediated type are characterized by the late appearance of symptoms. Objective: to evaluate the accuracy of the late-reading skin test, also known as atopy patch test for predicting oral tolerance after treatment with exclusion diet in patients with the diagnosis of non-IgE-mediated cow's milk protein allergy and gastrointestinal symptoms. Methods: A cross-sectional study with the participation of 32 patients diagnosed with non-IgE-mediated cow's milk protein allergy with gastrointestinal manifestations. After at least of 90 days on diet exclusion, the patients performed atopy patch test with 3 different cow’s milk protein preparations (in natura 2% in saline solution and 2% in petrolatum) and the oral food challenge. Results: Six (18.7%) patients presented positive oral food challenge. No differences in gender, onset symptoms age, oral food challenge age, Z-score, and exclusion period were found between positive and negative oral food challenge patients. Preparations in natura and with petrolatum presented sensitivity equal to zero and specificity 92.3% and 96.1%. The preparation in saline solution showed sensitivity and specificity of 33.3% and 96.1%. Conclusion: The results showed a low accuracy of atopy patch test for cow's milk protein in this group of patients and, therefore, remain not recommended for clinical use.