The outbreaks are accompanied by fever, leukocytosis, and eosinophilia.
Attacks are self-limited, lasting two to three weeks.
Slightly depressed pigmented areas may remain. In a variant of this disease, the lesions may undergo liquefaction and drain white, viscous material consisting of necrotic adipose tissue. Localization of the inflammatory nodules in periarticular areas leads to apparent acute arthritis of one or more joints, but studies of synovial fluids or synovial tissues are lacking. Histologic features of lupus panniculitis include subcutaneous lymphocytic infiltration, vasculitis, and deposition of complexes in vessel walls. Systemic nodular panniculitis may be distinguished from nodular vasculitis in that the lesions of nodular vasculitis are chronic, slightly tender, firm subcutaneous nodules that usually occur on the back of the legs.