[Chromium-induced vasculitis-like purpuric allergic contact dermatitis]

Purpuric allergic contact dermatitis is a rare and poorly understood condition.

A 27-year-old male patient with a personal history of atopic dermatitis since childhood consulted for chronic papular-purpuric rash present for 7 years. Moderate pruritus was seen. Profuse lesions were observed on the palms and soles and on the upper and lower limbs, with sparing of the trunk. These lesions consisted of purpuric papules, in some cases with crusts, forming large plaques. The clinical picture was initially suggestive of vasculitis, but this diagnosis was ruled out by histological examination and laboratory tests. Skin patch tests were evocative of chromium-induced contact dermatitis. Retrospective directed history-taking confirmed the relevance of the latter test since it revealed regular wearing of leather clothing. Lasting cure was achieved following eradication of the allergen.

Reports of contact purpuric dermatitis are rare. This condition has been described principally for allergens consisting of rubber or dyes used in clothing. Our case was notable on account of the severity of the lesions, mimicking vasculitis, as well as the novelty of the incriminated allergen, chromium, found in leather garments. It underlines the value of routine skin patch tests in the event of chronic non-specific dermatitis. To our knowledge, this is the first reported case of chromium-induced purpuric allergic contact dermatitis.