The objective of this study is to evaluate the efficacy, toxicity, and long-term outcome of low-dose IV cyclophosphamid therapy with repeated frequent intervals in combination with oral and IV methylprednisolone in patients with SLE nephritis. In this study, 113 patients diagnosed as having SLE and glomerulonephritis were assessed in between 1993 and 2002, with a median follow-up of 44.1+/-41.2 months. The patients were treated with 500 mg IV cyclophosphamide and 1 g IV methylprednisolone together with 60 mg/alternate-day oral methylprednisolone in a given schedule. The clinical and laboratory data were evaluated. There were significant improvements in the clinical and the laboratory parameters. Six patients died shortly after being hospitalized due to the disease activity itself. Eight patients were excluded from the study because of low compliance. The renal functions of the patients remained stable throughout the therapy; only 16/99 patients needed one or two additional pulses. Temporary leukopenia developed in 18/99 patients and diminished with the suspension or prolongation of the IV cyclophosphamide administration. Gastrointestinal side effects, which needed extra medication, developed in 20 patients. Hematuria was observed in 6/99 patients. Menstrual abnormalities were seen in 7/99 patients. No serious infections due to immunosuppression were observed with the given regimen. Hypertension was observed in 13 patients (minimum of 140/90 mmHg, maximum of 190/110 mmHg) and controlled with angiotensine-converting enzyme inhibitors. Mild central obesity was observed in 15 of the patients. Leimyosarcoma was observed in one patient who died during the follow-up period. Therapy starting with the weekly low-dose IV cyclophosphamide to induce remission together with IV and oral steroids, followed by prolonged intervals with the same doses for 2 years, appears to be useful in preserving renal function without major side effects in patients with lupus nephritis, in comparison to other studies.