The prevalence of CMA/CMPI in young children: the validity of parentally perceived reactions in a population-based study.

Abstract

The present study aimed to estimate the prevalence of adverse reactions to milk, as population-based prevalence estimates based on objective diagnostic procedures are rare. Children with parentally reported reactions to milk were selected for further examination from a population-based cohort of 2721 children. At the age of 2(1/2) years, they underwent a stepwise diagnostic procedure that included diet trials at home, skin prick tests, and open and double-blind, placebo-controlled food challenges. A sample of children with symptoms not attributed to milk was selected for assessment of unrecognized reactions. The estimated point prevalence of cow's milk allergy and cow's milk protein intolerance (CMA/CMPI) in children with parentally perceived reactions at the age of 2(1/2) years was estimated to be 1.1% (CI 0.8-1.6). However, this was an underestimate, as unrecognized reactions were detected. Most reactions were not IgE-mediated. The positive predictive value of a parentally perceived reaction depended on the number of times it had been reported and was good for reactions reported three times (at 12, 18, and 24 months of age). The present study confirms previous findings that parents overestimate milk as a cause of symptoms in their children; however, it also indicates that unrecognized reactions may be a problem as well.