[Progressive lipodystrophy (Barraquer-Simon syndrome): differential diagnosis and clinical aspects].

"Progressive lipodystrophy" or "partial lipodystrophy of the cephalothoracic type" is a rare, acquired condition of unknown aetiology with onset in childhood and a complete loss of subcutaneous fat of face, neck, trunk and upper extremities. The disease is more common in females than males and causes a disfigurement of the face; that it cannot be regarded only as a harmless variation, is above all due to a typical concomitant disease, membranoproliferative glomerulonephritis with hypocomplementaemia. Laboratory investigations nearly always reveal a complement-activation by the "alternative pathway" with consumption and lack of complement-component C3, a finding which allows a clear distinction between partial lipodystrophy and congenital or acquired forms of total lipodystrophy ("Berardinelli-Seip-Syndrom", lipoatrophic diabetes) and other circumscript lipodystrophies.