Dermatitis herpetiformis

Dermatitis herpetiformis is the oldest of the atypical clinical forms of coeliac disease. It occurs in subjects who are genetically predisposed to abnormally react to the gluten. It is also the most frequent autoimmune bullous disorder of childhood. The females are slightly outnumbered by the males. The average age of onset in children is five years. Pathologically, dermatitis herpetiformis is characterized by microabscesses of polymorphonuclear leukocytes at the top of the dermal papillae and by a concomitant subatrophy of intestinal villi. Granular IgA deposits can be shown at the top of the dermal papillae by direct immunofluorescence. Clinically, the disease is characterized by severe pruritus. After atopic dermatitis, scabies and papular urticaria it is the most frequent disorder among the chronic itchy skin diseases. Morphologically, in childhood the erythematous and papular gyrated, scarcely exudative lesions prevail and are mainly localized on the trunk. Besides the pathological findings and the direct immunofluorescence, the presence of antiendomysium antibodies confirms the diagnosis. The latter investigation is sensible and specific in unveiling the gluten-dependent enteropathy, decreasing the importance of the intestinal biopsy. The treatment of choice of dermatitis herpetiformis is the gluten-free diet, which must be continued for a long period of time or throughout life according to many authors.