Treatment outcomes and predictors in patients with idiopathic membranous nephropathy

Shin, Hyun Phil; Lee, Sang Ho; Lee, Tae Won; Kim, Myung Jae; Ihm, Chun Gyoo

Abstract

BACKGROUND: Idiopathic membranous nephropathy (IMN) is the most common cause of nephrotic syndrome in adults but the treatment regimen and the prognosis of IMN are controversial issue. Immunosuppresive treatment was preferably used in patients with high risk factors related to renal failure. We studied biopsy-proven idiopathic membranous nephropathy to evaluate clinical predictors for risk stratification and treatment outcomes according to regimens.
METHODS
66 patients (51 male, 15 female) with biopsy-proven IMN at our hospital during the period of 1991 to 2001 were studied retrospectively. Clinical information and data were obtained at the time of presentation and followed up regularly. We used several different treatment regimen according to patients compliance, clinical and laboratory data. Seven patients were treated with conservative management, 12 with oral steroid alone, 47 with oral steroids and combination with oral cyclophosphamide (1~2 mg/kg/day for 6~12 months). The mean follow-up period was 53.4 +/- 34.2 month. Treatment oucomes and predictors were idetified.
RESULTS
At presentation, mean age was 45.5 +/- 14.7 years old and patients with nephrotic syndrome was 77.8%. Pathologic stages II (Ehrenreich and Churg classification) was most common (68.2%). After each treatment, 33.3% of the group treated with oral steroid alone showed partial remission (PR) and 33.3% showed complete remission (CR), in combination thrapy group (cyclophosphamide with steroids) 23.4% PR and 38.3% CR. During follow-up period, four patients (6.1%) developed into chronic renal insufficiency. We used multivariate analysis of prognostic factor associated with persistent CR and progression to chronic renal insufficiency (CRI). Initial response within one year after therapy and non smoking were predictior of persistnet CR and increased initial serum creatinine and old age was related to progression to CRI.
CONCLUSION
At the end of follow-up, immunosuppresive therapy including oral cyclophosphamide and steroids induced favorable effect and can be used for high risk patients.