Long-term comparison of high- and low-dose oral immunotherapy in children with anaphylactic cow's milk allergy.

Abstract

Background: Long-term evidence on maintenance doses of oral immunotherapy (OIT) for anaphylactic cow's milk allergy is insufficient.

Methods: We retrospectively compared the three-year safety, efficacy, and adherence between OIT with a maintenance dose of 200 mL of cow's milk (HOIT, 2009-2013) and 3 mL of cow's milk (LOIT, 2013-2019). Patients aged 6-18 years with a history of anaphylaxis reacting to ≤3 mL of cow's milk during oral food challenge (OFC) were included. Adverse symptoms, OFC negative rate after 2 weeks of avoidance, dropout rate, and immunological changes were compared.

Results: The median ages in the HOIT (n = 78) and LOIT (n = 99) groups were 8.1 and 7.8 years, with milk-specific IgE levels of 56.5 and 49.2 kUA/L, respectively. The percentages of doses triggering symptoms were 20.88%, 13.73%, and 7.31% in the HOIT group and 11.81%, 8.15%, and 6.30% in the LOIT group during years 1, 2, and 3, respectively. After 3 years, 29% of patients in the HOIT group passed the OFC with 200 mL, and 47%, 18%, and 5% of patients in the LOIT group passed the OFC with ≥25 mL, ≥50 mL, and 100 mL of cow's milk, respectively. After 3 years, the dropout rates were 24% and 11% in the HOIT and LOIT groups and milk-specific IgE levels decreased by 88% and 78% in the HOIT and LOIT groups, respectively.

Conclusion: HOIT enables higher dose consumptions. LOIT might be safer and have higher adherence in patients with anaphylactic cow's milk allergy.