Absence of cutaneous IgA in coeliac disease without dermatitis herpetiformis.

Skin biopsies from 17 patients with coeliac disease, but without dermatitis herpetiformis, were examined by direct immunofluorescence. In none of them was IgA detectable. In contrast, IgA was present in dermal papillae and/or in relation to the dermo-epidermal junction in 80 out of 83 patients with dermatitis herpetiformis. These findings confirm that cutaneous deposition of IgA at these sites is a very characteristic feature of dermatitis herpetiformis and is unrelated to coeliac disease itself.