A 48-year-old man presented with a 7-year history of an intensely pruritic rash on both buttocks and the perianal area. The rash began as a few small, red, scaly bumps that coalesced to form larger plaques over the years. The patient had no personal or family history of skin cancer or psoriasis. He was otherwise healthy and had no systemic symptoms. His only medications were chondroitin sulfate, glucosamine, and loratadine (Claritin). Physical examination revealed a large reddish brown, verrucous plaque larger than 10 cm in diameter involving both buttocks, the gluteal cleft, and the perianal area (Figure 1). Mild erosions were observed on the perianal mucosal surface. The patient had previously been treated for presumed psoriasis. However, his condition was recalcitrant to topical clobetasol propionate therapy. Subsequently, a punch biopsy was performed (Figure 2and Figure 3). A 2-month course of imiquimod alternating with fluorouracil has improved the patient's pruritus, but overall resolution of the plaque has been poor.
CARRIE ANN RC, SENAIT ANN WD, MOLLY AH, VINCENT L, Burch HW, LeClerq AH, Maize JC. Pruritic Natal Cleft Plaque—Quiz Case. Arch Dermatol. 2010;146(8):911-916. doi:10.1001/archdermatol.2010.171-a