Cow's milk protein allergy: A risk factor for infections in infants?

Background: Cow's milk protein allergy (CMPA) imposes a significant burden on the lives of infants and families and can cause various complications, but there are limited data on the clinical burden associated with infection. Objective: This study aimed to compare infection frequency, antibiotic use, and hospitalization rates between children with CMPA and healthy controls. Methods: Patients diagnosed with CMPA (IgE-mediated or non-IgE-mediated) in the pediatric allergy-immunology outpatient clinic and healthy infants admitted to the social pediatrics outpatient clinic were evaluated prospectively at initial visit, 6 months, and 12 months. Clinical characteristics, history of respiratory, skin, gastrointestinal, and urinary tract infections, antibiotic use, and hospitalization rates were analyzed. Results: Compared to controls, the CMPA group had significantly lower prevalence and duration of exclusive breastfeeding (p < 0.001 for both) and significantly higher income (p = 0.035), presence of siblings (p < 0.001), household size (p < 0.001), rate of suburban dwelling (p = 0.008), and rate of atopic dermatitis (p = 0.003). Rates of infection (all systems), antibiotic use, and hospitalization were higher in the CMPA group compared to controls (p < 0.001 for all) and among patients with IgE-mediated CMPA compared to those with non-IgE-mediated CMPA (p < 0.05 for all). Respiratory and skin infections were more common and gastrointestinal infections were less common in IgE-mediated CMPA compared to non-IgE-mediated CMPA (p < 0.001 for all). Conclusion: CMPA (especially the IgE phenotype) was associated with increased infection frequency and severity in infants. These findings suggest the need for a more careful approach to infection risk in patients with CMPA and the importance of disease control.