Nodular cystic fat necrosis in a patient with erythema nodosum.

Nodular cystic fat necrosis shows a distinctive spectrum of clinical and histological features. Most of the lesions are mobile subcutaneous nodules in regions vulnerable to trauma, such as the elbows, knees, and shins. There have been no reports of an association with other conditions. The histology is characterized by encapsulated fat necrosis in which multiple, non-viable adipocytes are surrounded by condensed fibrous tissue. We report a case of early stage nodular cystic fat necrosis associated with erythema nodosum.