1Serviço de Imunoalergologia, Hospital de Dona Estefânia, Centro Hospitalar de Lisboa Central EPE, Lisboa, Portugal
- Eur Ann Allergy Clin Immunol 2019 Nov 27. doi: 10.23822/ [Epub ahead of print]
Resumo: Cut-off values for both skin prick tests (SPT) and specific IgE (sIgE) levels for predicting cow´s milk allergy (CMA) diagnosis are not universally defined. This study is a retrospective analysis of consecutive children (0-18 years-old) with suspected CMA tested with SPT and sIgE for cow's milk (CM) and its fractions between 2016-2017. CMA diagnosis was defined by a positive oral food challenge or a highly suggestive clinical history of CMA and SPT and/or sIgE positive to CM and/or its fractions. One hundred and five patients were included, 58% males with a median age of 2.5 (P25P75:1-6) years and the diagnosis was confirmed in 83 patients (79%). The variables associated with CMA diagnosis were SPT with CM (p<0,05) and casein (p<0,05) and all sIgE to CM and its fractions (α-Lactalbumin, β-Lactoglobulin and casein; p<0,05 for all). Optimal cut-off points (Youden’s index) for CMA diagnosis were 4.5 mm for the mean wheal diameter to cow's milk and 3mm to casein. For sIgE levels the optimal cutoff points were: for CM: 4.36 kUA/L, α-lactalbumin:1.6 kUA/L, β-lactoglobulin:1.7 kUA/L and for casein 2.6 kUA/L. The role of SPT and sIgE levels to cow´s mik and its fractions is unequivocal in CMA follow-up. Moreover, sIgE levels seem to be more discriminatory than SPT.
Palavras Chave: IgE; Milk Allergy; Sensitivity; Specificity; Skin Tests