Screening for Cow Milk Allergy in Infants and Preschool Children

Background Cow milk allergy (CMA) is the third most common food allergy that triggers anaphylactic reactions. Lactose intolerence, infantile colic and gastroesophageal reflux are the most common conditions which overlap with CMA causing both over and underdiagnosis. There are no wide population based epidemiological studies for the prevalence of CMA among Egyptian children. We sought to evaluate the prevalence of CMA among infants and preschool children and to correlate the parental reporting of CMA to the available diagnostic tools. Methods We conducted a cross sectional study that included 800 Egyptian children aged 3 months -5 years, who were enrolled consecutively from the primary care units and outpatient clinics of Children’s Hospital, Ain Shams University. Detailed history taking and clinical examination were done and those with suggestive history of CMA were subjected to further evaluation including skin prick test (SPT) and oral challenge test (OCT). Results The study comprised 390 girls (48.8%) and 410 boys (51.2%). Their weight centiles ranged between 5th and 97th percentiles, with median (IQR)=25(5-50) percentiles and mean(SD)=36.1(31.9). CM was introduced at age of 1-12 months, mean (SD): 9 (6) months with median (IQR): 12 (9-12) months. Forty (5%) subjects had suggestive history of CMA, 32 of whom completed their evaluation. The diagnosis of cow milk allergy was confirmed in 8/40 children (20%), comprising 1 % of the whole study sample. CMA was probably excluded at the time of the study in 21 subjects (52.5%), while diagnosis remained undetermined in 11/40 cases (27.5%) (8 refused to undergo SPT & OCT while 3 were lost to follow up). Conclusion The prevalence of CMA in Egyptian infants and preschool children is estimated to be around 1 % with possible overestimation of cow milk allergy diagnosis according to parental reports.