A 48-year-old man presented with a 4-month history of papular hyperkeratotic diffuse lesions on his trunk, arms, and neck that were highly pruritic (Figure 1). He also had "V"-shaped nicks in the nails, mucous white papules on his palate, and diffuse desquamation on the scalp. Abnormal laboratory values included elevated levels of uric acid and triglycerides. Serum electrolytes, blood sugar, and renal and liver function test results were within normal range. X-ray film and abdominal ultrasonography findings were also normal. Histopathologic study of the biopsy from the thorax revealed acantholysis with suprabasal clefting, intraepidermal lacunae, and dyskeratosis with corps ronds. The clinical features and results of the histopathologic studies suggested a diagnosis of Darier disease (Figure 2), but the course was not typical of this entity because the patient had no family or personal history of previous cutaneous lesions and the age of onset was older than usual. In the course of the disease, he developed blisters and small black hemorrhagic macules with jagged borders on the back of his hands (Figure 3). Nikolsky's sign was negative. A biopsy of a blister was performed, which confirmed Darier disease, studied by means of immunofluorescence. Measurement of porphyrins in the urine was also ordered. Direct immunofluorescence did not show deposition of immunoglobulins or complement, and the study of porphyrins was normal. The patient was treated with an oral retinoid (acitretin 10 mg daily), but treatment was stopped because he developed an increase in triglycerides; therefore, control of the disease with oral antihistamines, 5-fluorouracil 1% cream, and topical tazarotene was used, with mild improvement.