Lupus nephritis. Clinical course as related to morphologic forms and their transitions.

An intensive study of the course of lupus nephritis has been undertaken in 88 patients in whom strict morphologic criteria were utilized in classification. All were treated with steroid, and 17 received cytotoxic drugs in addition. Focal proliferative lupus nephritis generally follows a benign course except in the occasional instances when transition to the diffuse proliferative or membranous forms occurs. Membranous lupus nephritis, when characterized by persistent nephrotic syndrome, leads slowly to renal failure, but this progression is aborted in the one-third in whom remission of the nephrotic syndrome can be achieved. A fatal outcome occurs within five years in the majority of those with diffuse proliferative lupus nephritis and the nephrotic syndrome, often in association with necrotizing renal vasculitis, severe hypertension and accelerated renal failure. A small number with the diffuse proliferative form have a remission and then show only mesangial abnormalities, usually, however, with the appearance of glomerular sclerosis. Progressive glomerular sclerosis is observed in some patients and may be a sequel of the remission of the diffuse or focal proliferative lesions, or it may represent still another form of lupus nephritis. Mesangial immune deposits with or without proliferation, at times in the absence of clinical renal disease, are observed early in the course of systemic lupus erythematosus (SLE) and may proceed to the diffuse proliferative or membranous forms. The present observations serve to emphasize the importance of strict morphologic classification in the comparison of different treatment regimens for lupus nephritis. In view of the grave prognosis of established diffuse proliferative lupus nephritis, which probably evolves from a mesangial involvement common to all patients with SLE from its onset, early therapy may be the key to the management of lupus nephritis.