Small-bowel changes in dermatitis herpetiformis

A case of small-intestinal mucosal atrophy

A patient is described with a severe malabsorption syndrome which failed to respond to a gluten-free diet. Although subtotal villous atrophy was present in the jejunal mucosa, histological features of subepithelial fibrosis and apparently normal enterocytes were not suggestive of coeliac disease. The findings of decreased mucosal thickness, of a normal mitotic rate in the crypt cell population, and of the decreased rate of loss of epithelial cells further suggested that the disease process producing the ;flat' mucosa was not that of coeliac disease. The condition was complicated by ileal ulceration and active tuberculosis.

The effect on jejunal mucosa of withdrawing and adding dietary gluten in cases of idiopathic steatorrhoea

Biopsy studies of the jejunal mucosa in patients with idiopathic steatorrhoea after periods on a gluten-free diet showed that the epithelium improved quickly in respect of surface cell height, mucosal thickness, and mitosis count, and more slowly in respect of villous height and width. In no case was recovery complete in every particular. Appearances seen through the dissecting microscope improved slowly and incompletely. Gluten loading after a period on a gluten-free diet partially reversed some of these mucosal changes in as short a time as five to seven days. Measuring such changes may help to hasten the diagnosis in some patients with suspected gluten-sensitive enteropathy in whom there is otherwise difficulty in assessing the clinical response to a gluten-free diet. The histological response of the jejunum to a gluten-free diet and to subsequent gluten loading may help to clarify the aetiological relationship between carcinoma and jejunal mucosal atrophy.

Small intestinal mucosal abnormalities in relatives of patients with dermatitis herpetiformis

Jejunal biopsy has been carried out in 19 relatives of patients with dermatitis herpetiformis and stereomicroscopic abnormalities have been found in seven. The majority of the relatives in whom these abnormalities were found had no bowel symptoms: one had the rash of dermatitis herpetiformis. All but one of the propositi of the relatives in whom were found small intestinal mucosal abnormalities themselves had the coeliac syndrome. It is concluded that a genetic factor is involved in the production of the enteropathy of dermatitis herpetiformis as in other forms of the coeliac syndrome.

Dermatogenic enteropathy

Steatorrhoea has been found in a large proportion of patients with inflammatory dermatoses, especially eczema and psoriasis. It is due to the rash itself and disappears rapidly after topical treatment of the skin. This particular enteropathy, unlike that associated with dermatitis herpetiformis, is not accompanied by an alteration in the stereomicroscopic appearance of the small bowel mucosa. The mechanism is not known. It is important to differentiate dermatogenic enteropathy from gluten sensitivity which has produced a rash, as in the former condition a gluten-free diet is not indicated.

Results of treatment of dermatitis herpetiformis with a gluten-free diet after one year

Twenty-one patients with dermatitis herpetiformis initially controlled by dapsone or sulphonamides have been treated with a gluten-free diet and reassessed at intervals for up to 15 months (mean 11.9 months). According to routine histological and dissecting microscope criteria the small-bowel lesion improved in 10, but when mean epithelial cell height was used as a measure 15 patients improved. Five of the patients with diarrhoea improved after withdrawing gluten from the diet but none reverted to completely normal bowel habit. The tests for malabsorption showed little improvement in the treatment period. Twelve patients needed less dapsone to control their skin complaint, the mean dose falling from 144 mg. to a mean of 70 mg. per day; of these three stopped using this drug altogether.

Dermatitis herpetiformis in two patients with idiopathic steatorrhoea (adult coeliac disease)

Two patients who had had idiopathic steatorrhoea for several years developed typical eruptions of dermatitis herpetiformis. In each case the rash responded to treatment with dapsone.It is more usual for the rash to precede the enteropathy when the two occur together, but the association between coeliac disease and dermatitis herpetiformis is not yet clear.