Atypical Skin Rash in a Patient with Adult-Onset Still's Disease: A Case Report.

Adult-onset Still's disease (AOSD) is an uncommon idiopathic disorder with various clinical manifestations. The absence of specific serological and pathological findings often makes the disease difficult to diagnose. The presence of skin lesions is important to the correct diagnosis of the disease. Various atypical skin lesions have been reported in association with Adult-onset Still's disease. We present a 52-year-old male who had atypical cutaneous manifestations of Adult-onset Still's disease. The rash manifested as persistent, pruritic, dark reddish, confluent, erythematous maculopapules and plaques on his chest, abdomen, upper back and proximal extremities. He suffered high, spiking fevers and had marked elevations of ferritin, C-reactive protein, and the erythrocyte sedimentation rate, which are characteristic of Adult-onset Still's disease. The fever and systemic symptoms improved after the administration of intravenous pulse methylprednisolone therapy. The skin lesions improved after prednisolone and methotrexate combination therapy. Therefore, to make the correct diagnosis, it is important to understand that patients with Adult-onset Still's disease may present with various types of skin lesions.