D2.193 - Oral Induction of Tolerance to Cow's Milk Protein Allergy in Omani Children: A Retrospective Analysis

Cow's milk protein allergy (CMPA) is a common food allergy affecting Omani children. Although precise national incidence and prevalence figures are lacking, it is estimated to account for 14% of all anaphylaxis cases in Oman. Various CMPA management protocols exist, emphasizing efficacy, safety, patient selection, and long-term outcomes. At the Royal Hospital, oral induction of tolerance (OIT) for CMPA commenced in 2021, utilizing a six-item food protocol administered both in-hospital and at home, with telemedicine employed for monitoring.

A retrospective cross-sectional analysis of children undergoing CMPA OIT at the Royal Hospital was conducted in September 2024. CMPA diagnosis was established through clinical history and allergy testing. The food protocol included: Britannia® milk bikis biscuits (85g, containing 4% bovine milk), cake, pancake, cheese, yogurt, and fresh cow's milk. Foods were prepared according to iMAP milk ladder recipes or equivalents. Descriptive statistics and appropriate statistical significance tests were used to analyze collected clinical data.

Thirty Omani children (age range: 1-12 years; half the children were aged three years or younger; male:female ratio 2.1) were included. Symptom onset ranged from 1 to 24 months (mean: 7.4 months, median: 6 months). Nine children presented with atopic dermatitis, and seven with bronchial asthma. Four children were using amino acid-based formula, while nine tolerated extensively hydrolyzed formula at the initiation of OIT. Presenting symptoms were predominantly cutaneous, followed by gastrointestinal and respiratory manifestations (Figure 1). Seventy percent of children initiated the OIT program with biscuits. No anaphylaxis occurred during or after the program, and no correlation was found between allergy test positivity and OIT course. At the time of analysis, 14 children completed OIT, 7 were ongoing, 6 terminated, and 3 defaulted (Table 1).

This study demonstrates that OIT using a stepwise food introduction protocol is a safe and effective approach for managing CMPA in Omani children. Caregivers reported the approach as highly beneficial, particularly in inducing tolerance and preventing serious reactions from accidental milk ingestion. Future research should include a comparative analysis with a control group, long-term follow-up on tolerance and atopy development, and the incorporation of biological markers.