Hydrolyzed versus nonhydrolyzed protein diet in short bowel syndrome in children.

Abstract

To the Editors: We read with interest the paper by Ksiazyk et al. Previous studies by Adibi and others (1) have demonstrated that hydrolyzed proteins, which provide dipeptides as well as amino acids, confer a significant absorptive advantage over amino acid preparations alone. For this reason, hydrolyzed protein formulas have been popularized for use in patients in whom absorptive capacity is limited. However, Ksiazyk et al. have demonstrated no absorptive advantage to the administration of hydrolyzed versus nonhydrolyzed proteins for children with short bowel syndrome. This is certainly consistent with observations made by clinicians who care for children with short bowel syndrome. These children, although they may have a limited capacity for carbohydrate and fat absorption, usually absorb protein quite well, regardless of form. We would agree with the authors that there is little need from the standpoint of absorptive capacity to use hydrolyzed protein diet for the purpose of enhancing absorption. However, children with short bowel syndrome, especially young infants, may have a significant risk of secondary non–IgE-mediated intestinal allergic disease. Walker-Smith (2) and others have demonstrated that after mucosal injury, such as that produced by viral enteritis, secondary protein intolerance is a common phenomenon. Children with short bowel syndrome often have small intestinal dilatation and dysmotility, which results in small bowel bacterial overgrowth. Secondary inflammatory changes in the mucosa may occur which result in permeability to macromolecules, sensitization, and secondary allergic enteropathy. For this reason, extensively hydrolyzed protein formulas and even amino acid formulas may have a significant therapeutic advantage in the management of short bowel syndrome in patients younger than 2 years. These advantages are independent of the absorptive differences and are primarily related to the antiallergic properties of the extensively hydrolyzed proteins or amino acids. Although we agree that there may be little absorptive benefit produced by using hydrolysate formulas in short bowel syndrome, there remains a role for protein hydrolysate or amino acid formulas when inflammation is present. Jon A. Vanderhoof Rosemary J. Young