Aggressive gluten challenge of dermatitis herpetiformis cases converts them from seronegative to seropositive for IgA-class endomysial antibodies.

The responses to aggressive gluten challenge of two dermatitis herpetiformis patients with normal gut mucosa and negative serum findings for IgA endomysial antibodies while on normal diets indicate that these patients have a latent gluten-sensitive enteropathy. This was shown further by the control of skin lesions in both cases and in one case by the clearance of the induced gut lesions with a gluten-free diet. Specifically, for 12 to 20 weeks, aggressive gluten challenge (1 to 2 gm/kg/day) of these two patients was followed by both the appearance of and a rise in titer of IgA endomysial antibodies with an exacerbation of skin lesions. After 27 weeks of gluten challenge, histologic studies of the gut showed grade III flattening of the jejunal mucosa in the patient who developed IgA endomysial antibodies 19 weeks before biopsy was performed but not in the patient in whom IgA endomysial antibodies appeared 7 weeks before biopsy was performed. When both patients were placed on a gluten-free diet, IgA endomysial antibodies titers showed negative findings and the skin lesions subsided. It was possible to discontinue dapsone treatment after 30 weeks on a gluten-free diet in one patient and after 33 weeks in the other. It is important to note in the patient who developed grade III (significant) gut pathology after gluten challenge that a third biopsy taken 59 weeks after starting a gluten-free diet revealed a return to a grade II (insignificant) level of villus atrophy. Thus if sulfones are contraindicated in such cases, patients can be treated successfully with a gluten-free diet.