A 17-year-old African American boy presented with worsening nonpainful palmoplantar hyperkeratosis, which he had since early childhood. Physical examination revealed disfiguring palmoplantar keratoderma (Figure 1), coalescing hyperkeratotic papules on the upper trunk area (Figure 2), and similar papules on the elbows and knees. A biopsy specimen from the upper back area was obtained for histopathologic evaluation and stained with hematoxylin-eosin (Figure 3).
Cook-Norris R, Shook BA, Wells MJ, Stetson CL. Seborrheic Distributed Papules With Palmoplantar Hyperkeratosis—Quiz Case. Arch Dermatol. 2005;141(6):779-784. doi:10.1001/archderm.141.6.779-b