Gluten-free diet remains a strong treatment option for dermatitis herpetiformis

Majority of patients with dermatitis herpetiformis (DH) are unable to regain gluten tolerance, a recent study has shown. A lifelong gluten-free diet (GFD) therefore remains warranted as a treatment option.

Researchers performed a gluten challenge on 19 DH patients (mean age, 58 years; 13 males) who had been adhering to a GFD for a mean of 23 years. The challenge involved daily consumption of 200 g of commercially available wheat bread for 3 days. Skin and small-bowel biopsies were obtained before and after the gluten challenge to assess DH and/or coeliac disease manifestations.

After the gluten challenge, 15 patients experienced rashes over a mean of 5.6 months, corresponding to an incidence rate of 79 percent. At postchallenge, 12 showed small-bowel mucosal atrophy and 10 had serum samples enriched with antibodies targeting transgutaminase (TG) 2.

Moreover, two patients who had no rashes developed high levels of immunoglobulin (Ig) A-class TG-2 targeted antibodies and had to discontinue the gluten challenge at 4 months. One other patient with no rashes showed villous atrophy upon small bowel biopsy at 12 months. Therefore, a total of 18 patients experienced relapse, with an overall rate of 95 percent.

Only one patient did not relapse, showing normal skin and gastrointestinal symptoms throughout the challenge period, as well as having normal biopsy findings. As expected, the prechallenge biopsies did not exhibit rashes nor IgA and TG3 deposits.