Mycophenolate mofetil treatment for therapy-resistant glomerulopathies.

BACKGROUND

The management of steroid-resistant glomerulopathies remains a clinical problem. In this trial, we report a clinical observation of 43 patients treated with mycophenolate mofetil (MMF) for steroid-resistant glomerulopathies.

METHODS

All patients underwent renal biopsies, and immunofluorescence and light microscopy examinations were conducted in all cases. All patients had been treated with prednisone at a dose of 1 mg/kg per day for at least 8 weeks. Of the 43 patients, 16 were treated with cyclophosphamide and five were treated with cyclosporine A before MMF started. The primary study outcomes were the change in the urinary protein excretion, serum creatinine, comparing the levels at the start of MMF treatment with those at the end of the MMF treatment period. Changes in renal function were also estimated with Modification of Diet in Renal Failure calculation. Wilcoxon signed-ranks test was used as appropriate to compare data from the start with data at the end of the treatment period.

RESULTS

The primary glomerular diseases represented included membranoproliferative glomerulonephritis in 23.2%, membranous glomerulonephritis in 18.6%, IgA nephropathy in 13.9%, focal segmental glomerulosclerosis in 9.3%, lupus nephritis (systemic lupus erythematosus) in 25.6% and pauci-immune glomerulopathy in 9.3% of patients. The mean follow-up time was 28.9+/-12 months. Before MMF treatment, 16 patients (37%) had nephrotic range proteinuria and 11 (26%) had renal insufficiency. The urinary protein before MMF treatment was 3.3+/-2.6 g/dL (0.6-9.6) and decreased significantly to 0.87+/-1.1 g/dL (0-5.5) at the end of the MMF treatment period (P=0.02). During treatment, complete remission was seen in 27 patients, partial remission in 10 patients and MMF failure in six patients. The serum creatinine level decreased significantly from 1.29+/-0.55 mg/dL (0.6-3.0) to 1.14+/-0.38 mg/dL (0.5-2.4) post MMF therapy (P=0.046). Using the four-variable Modification of Diet in Renal Failure formula, the glomerular filtration rate increased from 71.5+/-28 mL/min per 1.73 m2 to 78.1+/-27 mL/min per 1.73 m2 (P=0.021). Renal insufficiency resolved in seven of the 11 (63.6%) patients with renal insufficiency initially, two with membranoproliferative glomerulonephritis, two with membranous glomerulonephritis, one with focal segmental glomerulosclerosis, four with pauci-immune glomerulopathy, two with systemic lupus erythematosus nephritis, and in two patients de novo renal insufficiency developed.

CONCLUSION

In general, MMF was well tolerated, and most of the patients achieved remission and improvement of renal functions. MMF treatment appeared to offer benefits to problematic patients refractory to conventional therapies for glomerulopathies.