WHATʹS YOUR DIAGNOSIS? Multiple painful nodules on the back

A 43-year-old middle-eastern woman was visited with a 15-year history of multiple painful cutaneous nodules on her back. The first lesion appeared on her back when she was 28 years old. As she aged, the lesions became larger, more numerous, and more painful with cold or physical contact. Her medical history was not significant.The patientʹs medications included naproxen, calcium-D, and vitamins. Her family history was notable as her brother had developed similar cutaneous lesions. Physical examination revealed more than 30 pinkish papules, measuring up to 1 cm in diameter, in a grouped arrangement on her back (Figure 1). The complete blood cell count, serum chemistry profile, and serum erythropoietin levels were within normal limits. Abdominal ultrasonography was normal.A skin biopsy specimen was obtained from a nodule on her back (Figure 2).