Systemic lupus erythematosus, partial lipodystrophy and hypocomplementemia.

A patient with partial lipodystrophy, increased susceptibility to infection and a clinical picture compatible with systemic lupus erythematosus is described. This patient had persistently low serum C3 levels and a C3-cleaving factor similar to the C3 nephritic factor (C3NeF). During periods of disease inactivity, serum levels of the other components of the classical and alternative pathways of complement measured were normal; heat labile opsonic capacity was low, suggesting functional depletion of factors of the alternative pathway of complement activation.