Allergy to cow's milk proteins in mother's milk or in hydrolyzed cow's milk infant formulas as assessed by intestinal permeability measurements

An intestinal permeability test analyzing the differential urinary elimination of lactulose and mannitol orally ingested at the same dosage allowed us to establish a significant correlation between alterations of intestinal permeability and ingestion of reputedly hypoallergenic foods, breast milk, and hydrolyzed protein formulas in some infants with cow's milk allergy. In all, clinical disappearance of symptoms was observed after removal of milk from the mother's diet and/or elimination from the child's diet of any cow's‐milk‐based hypoallergenic formula.