Dermatitis herpetiformis: relation between circulating antibodies against reticulin and gluten, small-intestinal mucosal status and absorptive capacity.

The status of the jejunal mucosa and of the intestinal absorptive capacity were investigated and related to the occurrence of antibodies against reticulin and gluten in 55 patients with dermatitis herpetiformis (DH), 28 on a normal, 11 on a gluten-reduced and 16 on a gluten-free diet. The mucosal status was characterized on the basis of histopathological findings and the numbers of intra-epithelial lymphocytes. Absorption was evaluated by 5-h urine and 1-h serum D-xylose tests. There was a positive correlation between the degree of pathological mucosal changes, malabsorption and the occurrence of circulating antibodies against reticulin and gluten. The serum xylose test was more sensitive than the urine xylose test for screening of the relatively mild enteropathy of DH and identified 88% of the patients with an abnormal mucosal status. The serological test (antibodies to reticulin and gluten) identified 80% of such patients. Among patients on a gluten-free diet there was some discrepancy between the serum xylose and the serological test, in that 5 of the 16 patients on this diet had an abnormal serum xylose test result, but no antibodies. In DH patients on a normal diet, the presence of antibodies to reticulin and gluten provided the same information about the presence of mucosal lesions as the serum xylose test. In the whole material a combination of the serum xylose test and the serological test identified 24 of 25 patients with an abnormal mucosal status.