Adverse Events in Oral Immunotherapy for the Desensitization of Cow's Milk Allergy in Children: A Randomized Controlled Trial

Background This study focuses on the side effects of cow's milk oral immunotherapy (CM-OIT) using consensus definitions of food-induced anaphylaxis. Objective To evaluate the risk of allergic reactions (ARs) and to identify risk factors associated with higher risk of anaphylactic ARs (AARs) during CM-OIT in children. Methods Clinical charts of children receiving CM-OIT were carefully reviewed. ARs were defined as single-organ ARs, and AARs were defined as involvement of 2 organ systems and/or hypotension in response to CM protein. Descriptive statistics were used to represent demographics, occurrence, reaction characteristics, and comorbidities. Poisson analysis was performed to evaluate risk factors associated with AARs. Results Among 41 children undergoing CM-OIT, 11 discontinued the treatment (N = 26.8%). The mean age at challenge was 12.1 years (standard deviation [SD], 3.6) and half were male (56.1%). The mean number of AARs per patient was 6.0 (SD, 3.5) versus a mean of 17.4 (SD, 11.9) non-AARs per patient. Among withdrawals from OIT, the mean number of AARs per patient was 8.3 versus 5.1 in nonwithdrawals. AARs were more frequent in children with higher specific IgE (sIgE) for α-lactalbumine and casein at baseline (1.11 [95% confidence interval (CI): 1.01, 1.22] and 1.01 [1.0, 1.03], respectively). Children with resolved eczema and higher sIgE for β-lactoglobuline at baseline (0.13 [95% CI: 0.04, 0.46] and 0.96 [95% CI: 0.94, 0.99], respectively) were less likely to develop AARs. Conclusions Although the majority of ARs during OIT are nonanaphylactic, AARs occur frequently. Children with higher sIgE for α-lactalbumine and casein at baseline seem to be at higher risk for AARs during OIT.