For six months, a single painful nodule on the right lower leg of an 85-year-old man in eastern China multiplied, and some of the bumps merged into plaques. By the time dermatologists examined him, the lesions were covered in thick, dark gray crusts that looked like oyster shells.
A biopsy pointed away from infection, cancer, and psoriasis. The diagnosis was verrucous porokeratosis, a rare variant of a group of disorders in which skin cells mature abnormally. His doctors at Zhuji People's Hospital in Zhejiang Province described the case in Clinical, Cosmetic and Investigational Dermatology on Sept. 14, writing that, to the best of their knowledge, it is the first reported case of rupioid porokeratosis on the lower leg.
