The effects of cytotoxic therapy in progressive IgA nephropathy

IgA nephropathy (IgAN) is not always benign, and some patients at high risk of end-stage renal disease (ESRD) experience a rapid decline in renal function. This study retrospectively examined the beneficial effects of cytotoxic therapy.

We identified 102 patients with progressive IgAN despite optimal conservative management. Of these, 31 who received cytotoxic therapy and 55 who were managed conservatively were included.

Median eGFR and urinary protein-to-creatinine ratio (uPCR) at baseline did not differ between the groups (p = 0.475 and 0.259, respectively). Median GFR slope was also similar (p = 0.896). Cumulative renal survival was better in the cytotoxic therapy group than in the control group (p = 0.009). Cytotoxic therapy was associated with lower risk of progression to ESRD, independent of eGFR, uPCR, GFR slope and kidney histologic findings (HR 0.13, 95% CI 0.03-0.66). In the cytotoxic therapy group, the median GFR slope decreased from -7.8 (-10.5, -5.0) mL/min/1.73 m(2) per year to -3.4 (-5.1, -1.8) mL/min/1.73 m(2) per year after treatment (p < 0.001). Mortality was not observed, but infection requiring hospitalization occurred at similar rates in both groups (p = 0.886).

Cytotoxic therapy attenuated the rate of GFR decline and was associated with a favorable renal outcome in patients with progressive IgAN.