Clinical course of patients with IgA nephropathy between combined treatment of immunosuppressive agents and ACE inhibitor and ACE inhibitor alone.

BACKGROUND: It has not been clear whether immunosuppressive therapy favorably influences renal function and proteinuria in IgA nephropathy (IgAN). Angiotensin converting enzyme inhibitor (ACEi) has an anti-proteinuric effect in IgAN. A retrospective study was done to see whether the addition of immunosuppressive therapy to ACEi produces a more excellent anti-proteinuric effect and preserves better renal function than ACEi alone.

METHODS: A total of 49 patients with proteinuria > 1.0 g/day and serum creatinine concentrations < 1.5 mg/dL were followed-up from at least 1 year to 9 years. Among them, 25 patients were treated with the combination of cyclophosphamide, prednisolone and ACEi while the other 24 were treated with ACEi alone.

RESULTS: The combination therapy or ACEi alone both reduced proteinuria with significant value (the combination group: from 5.74 +/- 5.08 to 2.29 +/- 2.77 g/day, ACEi group: from 3.85 +/- 2.54 to 1.68 +/- 1.91 g/day), while no significant differences in reduction of proteinuria were noticed between the two groups. There was no significant elevation of serum creatinine in both groups during follow-up (the combination group: from 0.91 +/- 0.20 to 1.03 +/- 0.38 mg/dL, ACEi group: from 0.93 +/- 0.27 to 0.99 +/- 0.37 mg/dL). This study showed no significant differences in the change in slope of 1/serum creatinine levels during the follow-up period between the two groups.

CONCLUSION: We conclude that immunosuppressive therapy may not be beneficial in patients with proteinuric IgAN. ACEi may be a valuable therapeutic agent avoiding serious side effects of immunosuppressive agents.