Should all patients with dermatitis herpetiformis follow a gluten-free diet?

Aim To assess the effect of a gluten-free diet in Irish patients with dermatitis herpetiformis, and whether treatment with a gluten-free diet is as important for patients with a normal small bowel biopsy us for those with villous atrophy. Background Though a gluten-free diet is recommended in the management of dermatitis herpetiformis, many patients find it intolerably restrictive. To date we have recommended it only to patients with abnormal small bowel histology. Methods Forty patients with dermatitis herpetiformis who attended our clinic between 1979 and 1994 were studied retrospectively. Villous atrophy was present in 20 (64%) of 31 initial small bowel biopsies in patients not on a gluten-free diet. Results The median time to a 50% reduction in dapsone requirements was 6 months in patients who followed a gluten-free diet. (n = 14). 10.5 months in those who had a gluten-reduced diet (n = 4) and 10.5 months in those who took a normal diet (n = 22). Four of 14 patients (29%) on a gluten-free diet were able to discontinue medication in 1–5 years compared with 2 of 22 (9%) on a normal diet. The mean time to a 50% reduction in dapsone requirements was similar in patients with and without villous atrophy. 9.3 versus 9.0 months in patients on a gluten-free diet and 12.0 versus 15.3 months in patients on a normal diet. Conclusion We conclude that a gluten-free diet should be strongly encouraged in all dermatitis herpetiformis patients, since those with normal small bowel biopsy findings benefit equally from the diet as do those with villous atrophy.