World Allergy Organization (WAO) Diagnosis and Rationale for Action against Cow's Milk Allergy (DRACMA) guideline update - XIII - Oral immunotherapy for CMA - Systematic review

Background: Allergy to cow's milk is the most common food allergy in infants and it is usually outgrown by 5 years of age. In some individuals it persists beyond early childhood. Oral immu-notherapy (OIT, oral desensitization, specific oral tolerance induction) has been proposed as a promising therapeutic strategy for persistent IgE-mediated cow's milk allergy. We previously published the systematic review of OIT for cow's milk allergy (CMA) in 2010 as part of the World Allergy Organization (WAO) Diagnosis and Rationale for Action against Cow's Milk Allergy (DRACMA) Guidelines. Objective: To systematically synthesize the currently available evidence about OIT for IgE-mediated CMA and to inform the updated 2022 WAO guidelines. Methods: We searched the electronic databases including PubMed, Medline, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), and the websites of selected allergy organizations. We included all studies irrespective of the language of the original publication. The last search was conducted in February 2021. We registered the protocol on Open Science Framework (10.17605/OSF.IO/AH2DT). Results: We identified 2147 unique records published between 2010 and 2021, including 13 randomized trials and 109 observational studies addressing cow's milk OIT. We found low-certainty evidence that OIT with unheated cow's milk, compared to elimination diet alone, increased the likelihood of being able to consume >= 150 ml of cow's milk in controlled settings (risk ratio (RR): 12.3, 95% CI: 5.9 to 26.0; risk difference (RD): 25 more per 100, 95% CI 11 to 56) as