Objective: We investigated the usefulness of skin prick test (SPT) using bifurcated needle (BN) for the diagnosis of cow's milk allergy (CMA) in early infancy.
Subjects and methods: Among atopic dermatitis infants with suspicion of food allergy who visited Sagamihara National hospital from January 2001 to April in 2005, 168 cases had received both SPT and IgE ImmunoCAP of CM (CM-IgE) at first visit. We analyzed results of SPT and CM-IgE, focused on infants with negative CM-IgE to examine the usefulness of SPT, and checked positive conversion of CM-IgE with aging.
Results: Among 124 infants (73.8%) with negative CM-IgE, 34 infants (27.4%) showed positive SPT results. Forty two infants (33.6%) among the 124 cases were diagnosed as CMA by combination of elimination and provocation test, and 21 infants (50.0%) had positive SPT. In the follow up study of 39 negative CM-IgE cases with CMA, 21 CM-IgE (53.8%) turned positive later infantile period (mean CM-IgE: 4.2+/-4.8 Ua/ml at 9.3+/-5.3 months old).
Conclusions: SPT using BN seemed to be more useful than CM-IgE for the diagnosis of CMA in early infancy with AD. But, the sensitivity is lower than in the egg case.