Treatment of idiopathic membranous nephropathy in 35 children

Objective To investigate the prognosis and efficiency of glucocorticoid and immunosuppressor in the treatment of idiopathic membranous nephropathy(IMN) in children. Methods A retrospective analysis of 35 cases of biopsy-proven membranous nephropathy without secondary factors was performed, who were found present with nephrotic proteinuria and admitted to hospital from March 2004 to July 2013, to explore the efficiency of treatment with glucocorticoid and immunosuppressor and its prognosis. Results The 35 IMN cases included 18 boys and 17 girls, and the ratio was 1.1∶1.0.The mean age at onset was (11.3±0.5) years with a range of 3.0-17.1 years.Five cases with gross hematuria, 24 cases present with microscopic hematuria, 8 cases with hypertension, 1 case with chronic renal insufficiency, and 2 cases were complicated with thrombosis.According to membranous nephropathy staging criteria, 9 cases(25.7%) were in stage Ⅰ, 16 cases(45.7%) in stage Ⅱ, 10 cases (28.6%)in stage Ⅲ; about 94.3%(33/35 cases) had mesangial cells and mesangial matrix with mild to moderate hyperplasia.They were all treated with glucocorticoid initially and one of them showed sensitive to flucocorticoid but developed flucocorticoid resistance after relapse, while all the others were flucocorticoid-resistant.Cyclophosphamide A(CsA) was introduced to 17 cases and at least lasted for 3 months, in which 13 cases(76.5%) reached complete remission and 3 cases reached partial remission, while 1 case didn't achieve remission, and the mean time for proteinuria to disappear was (4.9±3.7) months; 5 cases were treated with Mycophenolate mefetil(MMF), among which 4 cases reached complete remission in 2 months, 4 months, 5 months, and 9 months separately, while 1 case reached partial remission.Cyclophosphamide(CTX) was introduced to 6 cases, in which the mean cumulative dosage was (91.2±46.5) mg/kg, among them 1 case(87 mg/kg) reached complete remission, 1 case (160 mg/kg) partial remission, but 4 cases didn't achieve remission.One case reached remission after Rituximab(RTX) was introduced.One case got partial remission after Leflunomide(LEF) was introduced, and the complete remission rate was higher in those treated with combined therapy of glucocorticoid and CsA than those treated with glucocorticoid only(76.5% vs 12.5%, P=0.004), but the total efficacy showed no difference(94.2% vs 62.5%, P=0.081). The complete remission rate(76.5% vs 38.5%, P=0.042) and total efficacy(94.1% vs 61.5%, P=0.040) were higher in those with combined therapy of steroid and CsA than those treated with steroid and other immunosuppressor.The complete remission rate(76.5% vs 16.7%, P=0.018) and total efficacy(94.1% vs 33.3%, P=0.008) were also higher than those treated with steroid and CTX, but the complete remission rate(76.5% vs 80.0%, P=0.687) and total efficacy(94.1% vs 100.0%, P=0.773) showed no difference compared with those treated with steroid and MMF. Conclusions IMN shows glucocorticoid resistance mostly, while CsA had definite efficiency and may be better than CTX.And the efficiency of MMF should be noted. Key words: Idiopathic membranous nephropathy; Treatment; Child