Lipoatrophy is thought to be a postinflammatory state where there is loss of subcutaneous fat. Predisposing conditions for lipoatrophy include panniculitis, exogenous pressure, injection of medication, and antiretroviral therapy for HIV. Lipoatrophy is also a normal contributor to the appearance of an aging face.

Localized lipoatrophy has been subcategorized into the following: annular, abdominal, semicircular, and postinjection. These subcategories aim to describe clinical presentation, with the exception of postinjection lipoatrophy. The cause of lipoatrophy in annular, abdominal, and semicircular categories is thought to be postinflammatory.

Injection site lipoatrophy can be associated with insulin, corticosteroids, and antibiotics, among others, and history is a key component of making this diagnosis. Lipoatrophy associated with HIV is thought to result from antiretroviral treatment, although the exact mechanism is unknown.