Adverse events in oral immunotherapy for the desensitization of cow's milk allergy in children: a randomized controlled trial.

BACKGROUND: This study focuses on 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 co-morbidities. 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 (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 (SD11.9) non-anaphylactic ARs per patient. Among withdrawals from OIT, the mean number of AARs per patient was 8.3 versus 5.1 in non-withdrawals. AARs were more frequent in children with higher sIgE for alpha-lactalbumine and casein at baseline [1.11 (95% CI 1.01, 1.22) and 1.01(1.0, 1.03 ) respectively]. Children with resolved eczema and higher sIgE for beta - lactoglobuline at baseline [0.13 (95% CI 0.04, 0.46) ], [0.96 (95% CI 0.94, 0.99)] respectively, were less likely to develop AARs.

CONCLUSION: Although the majority of ARs during OIT are non anaphylactic, AARs occur frequently. Children with higher sIgE for alpha-lactalbumine and casein at baseline seem to be at higher risk for AARs during OIT.