Severity and extent of upper small bowel mucosal damage in cow's milk protein-sensitive enteropathy

A series of 31 infants, 28 with cow's milk protein sensitive enteropathy (CMPSE) and 3 controls, was studied for severity and extent of mucosal damage of the upper small bowel in relation to the development of clinical symptoms. Following challenge with the offending cow's milk, 18 infants (Group 1) developed severe mucosal changes at both the proximal and distal small bowel mucosa and all of these infants presented with clinical symptoms. The other 10 infants (Group 2) who did not develop clinical symptoms following the challenge had less severe damage to the distal small bowel mucosa as compared to the proximal region. The histological score of both the proximal and distal postchallenge biopsies were significantly lower in Group 2 as compared to Group 1 infants. The mucosal disaccharidase and alkaline phosphatase levels were depleted in both the proximal and distal biopsies following challenge but the depletion was greater in the proximal than the distal biopsies. It is suggested that the extent and severity of mucosal damage to the proximal duodenum and jejunum have a critical bearing on the development of clinical symptoms.