A NEW retrospective study suggests that a revised protocol for milk oral immunotherapy (OIT) may significantly reduce the severity of a troubling gastrointestinal side effect known as OIT-induced gastrointestinal eosinophilic reactions (OITIGER). The findings, drawn from data collected over more than a decade, offer encouraging evidence that protocol adjustments can make OIT safer for children undergoing treatment for milk allergy.
Understanding Milk Allergy and OIT-Related Reactions
OITIGER is characterised by abdominal pain and vomiting unrelated to the timing of OIT dosing. These reactions are often accompanied by elevated absolute eosinophil counts (AEC), a type of immune cell involved in allergic inflammation. Previous research has linked higher baseline AEC, higher starting doses, and rapid dose escalation to increased risk.
The study compared 269 patients who underwent OIT between 2017 and 2021 under a revised protocol, featuring a lower starting dose and slower dose increases, to 604 patients treated between 2010 and 2015 using the previous approach. While the overall rate of OITIGER remained similar between the two groups (8.2% in the revised cohort vs. 9.1% in the original), the severity of reactions declined markedly.
Among patients who developed OITIGER, only 45.5% in the revised-protocol group experienced severe symptoms, defined as vomiting three or more times per month. This represents a substantial reduction from the 72.7% severe-reaction rate seen under the earlier protocol. Statistical analysis confirmed the protective effect: the revised protocol reduced the odds of severe OITIGER by 70%.
The researchers also found that certain patient characteristics influenced risk. A baseline AEC greater than 600/μL more than doubled the likelihood of developing OITIGER, while older age offered modest protection. Notably, patients treated under the revised protocol experienced a smaller increase in AEC during therapy, suggesting a dampened inflammatory response.
Implications for Future Milk Allergy Therapy
Overall, the findings indicate that modifying OIT protocols, specifically by lowering the initial dose and slowing escalation, can reduce the intensity of gastrointestinal side effects without changing their overall frequency. The authors conclude that these adjustments may improve tolerability and patient outcomes in milk OIT, offering clinicians a valuable pathway to safer allergy desensitisation.
Reference
Epstein-Rigbi N et al. Decreased Severity of Oral Immunotherapy Induced Gastrointestinal Eosinophilic Reactions Following Revisions in Milk-Treatment Protocol. Allergy. 2025; doi:10.1111/all.70165.
