Confluent and reticulate papillomatosis.

A 24-year-old man had an asymptomatic rash on his chest and arms for one year. On his chest, there were brown confluent plaques in a reticulate pattern. A scraping for fungus was negative. A biopsy showed papillomatosis, orthokeratosis, and melanin pigment at the basal layer of the epidermis. The patient was started on a six-week course of minocycline twice/day. Six weeks later, the patient was completely clear of the rash. Confluent and reticulate papillomatosis is an uncommon dermatosis that tends to occur on the chest. The pathogenesis is unknown. Minocycline has been reported to work well in the treatment of this dermatosis.