Dietary gluten challenge does not influence the levels of circulating immune complexes in patients with dermatitis herpetiformis.

To examine the relationship between the gluten-sensitive enteropathy (GSE) and IgA circulating immune complexes (CIC) in dermatitis herpetiformis (DH) a series of dietary gluten-challenge studies were performed in patients with DH and patients with ordinary GSE. Serial serum samples were monitored for IgA-, IgG-, and IgM-containing CIC levels. In the first study, 9 DH patients and 5 controls were fed 20 g of gluten flour as a breakfast meal on 1 of 2 consecutive study days. DH patients did not develop or increase their levels of CIC after gluten-challenge or gluten-free meals. There was no significant difference between the DH patients and the control group in regard to development of CIC. To evaluate the effect of dietary gluten in another form, 8 DH patients were given meals containing 100 g of boiled Canadian cracked wheat. Two patients with ordinary GSE were also challenged with cracked wheat. Again there was no elevation or induction of CIC above baseline determinations by gluten-challenge meals. These studies suggest that dietary gluten does not induce the formation of CIC in patients with DH.