THE COURSE AND TREATMENT OF LUPUS NEPHRITIS

Renal involvement by systemic lupus is variable; some patients have mi nimal clinical and histologic involvement, whereas others have fulmina nt renal failure and severe proliferative renal lesions on biopsy. The World Health Organization (WHO) classification has greatly aided in t he study of lupus nephritis. This classification defines six major pat terns of renal involvement, each with characteristic clinical correlat es and a typical course and prognosis. Transfer mations from one patte rn of lupus nephritis to another may occur, and there may also be prom inent involvement of the tubulointerstitial compartment and vasculatur e. Treatment of the renal lesions may be directed at the individual cl ass of lupus nephritis. Thus patients with mesangial involvement (WHO Class II) do not require therapy directed at their kidney lesions. Man y patients with biopsies showing focal proliferative disease (WHO Clas s III) and all patients whose biopsies show diffuse proliferative lesi ons (WHO Class IV) require vigorous treatment, which has included high -dose daily and alternate-day corticosteroids, azathioprine, i.v. puls e methylprednisolone, plasmapheresis, total lymphoid irradiation, cycl osporine, and oral and i.v. cyclophosphamide. Controlled trials have y ielded reasonable evidence for the safety and efficacy of some treatme nts, whereas others have been used only in uncontrolled studies. When used judiciously, such vigorous therapy can improve the renal survival of patients with severe lupus nephritis.