Background: No definitive therapeutic consensus has been established for progressive immunoglobulin A nephropathy (IgAN).
Methods: We retrospectively investigated 35 patients with histologically advanced IgAN. The patients were divided into two groups: 27 received prednisolone and cyclophosphamide (PSL+CPA group) and 8 received supportive treatment (control group). The initial doses of PSL and CPA were 30 mg/day and 50 mg/day, respectively. PSL was tapered to 2.5 mg/day over 2 years and CPA was discontinued at 6 months.
Results: In the control group, mean follow-up duration was 22.9 months, renal progression rate was -20.9 x 10(-3) dl/mg per month, and all patients developed endstage renal disease within 5 years. In the PSL+CPA group, mean follow-up duration was 64.3 months, renal progression rate was -1.5 x 10(-3) dl/mg per month, and renal survival at 5 years was 89.8%. Renal prognosis was markedly improved in the PSL+CPA group compared with the control group. The patients in the PSL+CPA group were divided into two subgroups according to baseline serum creatinine (<2 mg/dl or > or =2 mg/dl); renal survival in the two subgroups was similar (84.4% versus 100% at 5 years). Adverse effects of PSL+CPA were minimal and mild.
Conclusions: It is possible that PSL+CPA therapy safely improved the renal prognosis of patients with severe IgAN who would otherwise have required dialysis therapy within 5 years. However, a prospective, multicenter clinical trial is required to prove the effects and safety of this treatment.