A 30-year-old man presented with a 15-year history of asymptomatic hyperkeratotic palmar and plantar plaques. The eruption initally appeared on his left palm. Over time, similar plaques appeared on his hands, feet, and scalp, with more severe plaques on the palms, resulting in limitation in hand mobility. The patient, a farmer, had no other complaints or history of major illness and had not taken any medication.
On physical examination, gray-yellow, papillary, horny excrescences, which had an unpleasant odor, were seen on the hands, more extensively on the palms (the lesions covered a total area of 18.0 × 11.5 cm on the left palm and 15.0 × 9.0 cm on the right palm). The skin underlying the lesions was thickened and erythematous. The left palm was almost completely covered with hard horny proliferations (3 cm in thickness), resembling a "cauliflower palm." Eight fingers were malformed (Figure 1 and Figure 2). The fingers of the left hand could not be flexed. Also, there were 3 or 4 hyperkeratotic plaques on the scalp and feet. On laboratory examination, the white blood cell count was 5.0 × 109/L (76% neutrophils, 22% lymphocytes, and 2% monocytes), the red blood cell count was 4.64 × 1012/L, and the platelet count was 108 × 109/L. Serological tests were positive for hepatitis B surface antigen, hepatitis B e antigen, and anti–hepatitis B core antigen. A more comprehensive examination of immunological function was not performed. A skin biopsy specimen was obtained from the back of the patient's left hand (Figure 3 and Figure 4).
Xu H, Yin H, Xi J, Wang G, Yu R, Goellner JR. Horny Excrescences on the Hands. Arch Dermatol. 2002;138(3):405–410. doi:10.1001/archderm.138.3.405
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