Dermatitis herpetiformis

Dermatitis herpetiformis (DH) is an inflammatory, autoimmune skin disease. It is considered the specific cutaneous manifestation of celiac disease (CD). Epidermal transglutaminase has been identified as the major autoantigen of DH. The high sequence homology between epidermal and tissue transglutaminase has been considered a possible causative explanation for DH and CD correlation. The clinical picture includes erythema, papules and grouped vesicles in a typical symmetrical distribution involving elbows, knees, shoulders, and buttocks. The itch is intense and can be one of the initial signs of DH. DH diagnosis may be challenging, due to its low prevalence and its clinical and immunological heterogeneity. According to the 2021 European Guidelines, diagnosis relies mainly on two major criteria: compatible clinical manifestations and a positive compatible direct immunofluorescence on perilesional skin biopsy. The only causative treatment for DH is gluten-free diet and it can be associated with symptomatic treatments until clinical remission is reached.