A healthy 17-year-old black male adolescent presented with an 8-year history of asymptomatic “warts” on both hands. Over-the-counter salicylic acid treatments and cryotherapy treatments with liquid nitrogen had resulted in no improvement. He was not taking any medications and had no family history of skin disease or personal history of chronic trauma, excessive sun exposure, arsenic ingestion, or other cutaneous lesions.
Physical examination revealed almost translucent, round to polygonal papules of varying sizes distributed symmetrically over the dorsal surface of the interphalangeal joints (Figure 1). Similar, smaller papules were clustered over the radial aspect of the thenar eminences (Figure 2). The papules were smooth, flat-topped, and flesh-colored, with slight hyperkeratosis. There were no other lesions on the extremities. A punch biopsy specimen was obtained from a papule (Figure 3).
Cabrera AR, Gilliam AE, Frieden IJ. Papules Overlying the Finger Joints—Quiz Case. Arch Dermatol. 2006;142(2):235-240. doi:10.1001/archderm.142.2.235-c