Prick-by-Prick Test with Pasteurised Cow's Milk: A Valuable Tool in Paediatric Practice

BACKGROUND: This study assessed the utility of a prick-by-prick test with pasteurised cow's milk in predicting a pasteurised cow's milk allergy (CMA) diagnosis. METHODS: This was a retrospective study of 86 paediatric patients who had undergone open pasteurised cow's milk oral food challenges (OFCs). We evaluated the diagnostic performance of a prick-by-prick test with pasteurised cow's milk in predicting a positive OFC result. We calculated the threshold values representing high test specificity and predictive probability in children aged ≤24 and >24 months. RESULTS: A prick-by-prick test with pasteurised cow's milk was a good classifier of a positive cow's milk OFC outcome. The mean prick − by − prick test wheal diameter ≥ 3 mm yielded 100% sensitivity in both groups of children. Thresholds representing high test specificity and 95% predicted probability were 7 and 11 mm in children ≤ 24 months and 11 and 17 mm in children > 24 months of age, respectively. CONCLUSION: A prick-by-prick test with pasteurised cow's milk is valuable in paediatric practice when diagnostic thresholds are implemented.