Escalation of soya cross-allergy in infants with cow's milk allergy.

Abstract

Background: Cow's milk allergy (CMA) is a common condition in infants, requiring alternative protein sources in their diets. Soya milk has become a popular substitute, especially in developing countries where it is a more affordable option compared to expensive hypoallergenic feeds for infants with insufficient breast milk supply. However, recent observations have shown an increase in soya cross-allergic reactions among infants with CMA.

Aim: To determine how often infants diagnosed with CMA also had soya cross-allergy and to examine the symptoms and outcomes of these infants at 2 years of age.

Methods: Data from two pediatric centers were analyzed, looking at clinical records of children under 2 years old diagnosed with CMA from August 2015 to July 2023, divided into two four-year periods.

Results: The records of 432 infants with CMA were analyzed. In the first four-year period from August 2015 to July 2019, 142 infants were studied, with 27 (19%) found to have soya-protein allergy as well. In the second four-year period, a total of 290 infants were studied, and soya allergy was found in 136 babies (47%). This represents a significant increase (P < 0.0001) in cases of soya protein cross-allergy among infants with CMA. The most common symptoms observed were gastroesophageal reflux disorder (39%), followed by failure to thrive, bloody diarrhea, watery diarrhea, and constipation. At 2 years of age, these infants showed significant growth failure compared to infants with CMA only.

Conclusion: In conclusion, this study emphasizes the importance of being cautious when using soy protein in infants with cow's milk protein allergy, especially in areas where cost is a major concern.