Lipoatrophic panniculitis, also known as lipophagocytic panniculitis and annular lipoatrophic panniculitis of the ankles, is an extremely rare, predominately lobular panniculitis that most commonly affects the lower extremities of children. It is characterized by recurrent, tender subcutaneous nodules with associated systemic symptoms (eg, fever, malaise, arthralgias). After the acute inflammation subsides, permanent lipoatrophy ensues.

Although this condition can affect adults, it is more common in children, predominantly affecting ages 3-13 years, and girls are affected more frequently than boys. Fewer than 5 of the reported cases to date have also presented with hepatomegaly or splenomegaly.

While the cause of lipoatrophic panniculitis is unknown, it may be associated with other autoimmune or autoinflammatory conditions (eg, insulin-dependent diabetes mellitus, Hashimoto thyroiditis, and juvenile rheumatoid arthritis). Neither physical trauma nor specific viral etiologies have been linked, although prior upper respiratory infections have been reported in some patients prior to onset. A genetic link has been postulated but not confirmed. One report suggests that a mutation in chromosome 10p (where alleles for the interleukin-2 [IL-2] receptor gene reside) is implicated.