Long-term efficacy of azathioprine treatment for proliferative lupus nephritis

Background. Combination therapy with cytotoxic drugs and corticosteroids re duces the risk for renal failure in patients with proliferative lupus nephr itis (PLN), but uncertainty remains about the best mode of immunosuppressio n and its long-term effects. We report long-term results of combined azathi oprine-prednisolone treatment for PLN, which has been the therapy of choice for the treatment of PLN at our centre for 15 yr. Patients and methods. A retrospective cohort study was carried out of 26 lu pus patients, seen between 1978 and 1993, with histological and/or clinical evidence of PLN. Therapy consisted of prednisolone 1 mg/kg daily, tapered after 4 weeks to the lowest possible maintenance dose combined with azathio prine up to 2.5 mg/kg. Median duration of azathioprine treatment was 53 mon ths. Standard statistical lifetable analyses were performed. Results. Median follow-up on 1 January 1998 was 119 months. Patient surviva l estimates after 5, 10 and 15 yr of follow-up were 96, 91 and 82%, respect ively. Four patients (15%) developed end-stage renal failure and three rece ived renal transplants after a mean period of 27 months on haemodialysis. R enal survival estimates after 5, 10 and 15 yr of follow-up were 92, 87 and 87%, respectively. No malignancies were seen during the study period. Conclusion. Azathioprine treatment for 4 1/2 yr was well tolerated in this cohort of Caucasian patients with PLN and was associated with outcomes simi lar to those reported for pulse cyclophosphamide therapy.