Soy protein sensitization in cow's milk allergy patients

Background The management of cow's milk allergy (CMA) is avoidance of cow's milk as strictly as possible. Extensive hydrolyzed protein and amino acid based formulas are recommended dietary products for treatment of CMA. However, they have some disadvantages, such as bitter taste and high cost. Alternative protein sources from vegetable proteins, such as soy, can be used as milk-substitute. Previous studies showed the prevalence of soy allergy in CMA patients in Western countries ranged between 0 to 63%, but the prevalence in Asia was not greater than 20% and no data about this prevalence in Indonesia. Objectives To determine the proportion of soy protein sensitization in CMA patients and characteristics of CMA patients who were sensitized to soy protein. Methods Fifty seven CMA patients who consumed soy protein were taken their blood sample to examine the soy-specific IgE. Results From 57 CMA patients, we found only 18% of patients who were sensitized to soy protein. Seven out of ten CMA patients who were sensitized to soy protein were under 12 months old. Atopic dermatitis was the most frequent clinical manifestation (8/10) and all of them had family history of atopic diseases. Soy sensitization in IgE-mediated and non-IgE mediated CMA were 6/10 and 4/10, respectively. Conclusions Proportion of soy sensitization in CMA patients in this study was 18%. Soy protein can be used as an alternative for cow's milk substitute in CMA patients.