Nodular cystic fat necrosis with calcification in a patient with juvenile dermatomyositis.

Nodular cystic fat necrosis is a rare, benign form of encapsulated fat necrosis with distinct histology, characterized by cystic fat necrosis with lipomembranous changes and, in later stages, calcification. We report the case of a 7-year-old child with juvenile dermatomyositis who presented with three asymptomatic, firm, mobile nodules on the arms and neck. Histology was consistent with nodular cystic fat necrosis with prominent calcification. This is an unusual presentation of this entity because it has never been previously reported in association with juvenile dermatomyositis.