Outcome of severe steroid-dependent nephrotic syndrome treated with mycophenolate mofetil

Mycophenolate mofetil (MMF) is used as a steroid-sparing agent in pediatric nephrotic syndrome (NS). However, data about its long-term efficacy and safety is limited.

We report the long-term outcome of MMF therapy in 46 NS patients who remained steroid dependent (SD) despite previous treatment with levamisole and cyclophosphamide.

After 1 year of MMF initiation, 32 (70 %) patients had reduced steroid requirement: 12 with decreased threshold dose and 20 were able to stop steroids. At follow-up of mean 3.56 (standard deviation + 1.76) years, 25 (54 %) children required no further alternative immunosuppression (IS), having infrequent or no relapses, of which 14 stopped MMF after a mean 2.4 (standard deviation + 0.9) years; 11 are continuing on MMF for a median of 2.25 years (range 1.33–7.75 years). One patient had a psoriasis flare, and MMF was stopped. No other patient required permanent drug withdrawal due to side effects. The outcome of patients who did not require further alternate IS was significantly better than those who did, with 56 % vs. 10.5 %, respectively, being off regular medications at last follow-up.

We conclude that MMF therapy is safe in the long term and allows >50 % of severe SDNS patients to avoid further toxic IS.