Histopathologic Diagnosis and Outcome of Renal Biopsied Pediatric Nephrotic Syndrome

Chung, Hye Jeon; Youn, Suk; Kim, Sung Do; Cho, Byoung Soo

Abstract

PURPOSE: To determine the histological findings and treatment outcome in cases of childhood nephrotic syndrome which required renal biopsy.
METHODS
We retrospectively reviewed the clinical, laboratory, pathologic findings and therapeutic outcomes of 169 nephrotic children who received a renal biopsy at the Department of Pediatrics, Kyunghee Medical University Hospital, Seoul from 1984 to 2004 over a period of 21 years. The renal biopsy was performed in nephrotic children who showed atypical features at presentation, or needed cytotoxic therapy because of frequent-relapsing, steroid-dependent, or steroid-resistant nephrotic syndrome(SRNS).
RESULTS
Minimal change disease(MCD) was found in 52.1% of the patients, followed by diffuse mesangial proliferation(33.1%), focal segmental gomerulosclerosis(5.3%), membranoproliferative glomerulonephritis(2.4%), membranous nephropathy(2.4%), and IgA nephropathy(1.8 %). In MCD children, 14.8% had hematuria, 22.7% had hypertension, 5.7% showed decreased renal function, and no patient was found to have an abnormal complement level. Among patients diagnosed with diseases other than MCD, 43.2% had hematuria, 21.0% was found to be hypertensive, 7.4% of children showed decreased renal function and only 3(3.7%) had decreased complement level; the rates of hematuria and SRNS were found to be significantly higher than MCD patients. Among 37 SRNS patients, 30(81.0%) showed a final remission state with long-term steroid therapy, including methylprednisolone pulse therapy, over 4 months, with or without cytotoxic therapy.
CONCLUSION
Almost half of the cases of childhood nephrotic syndrome requiring renal biopsy were not diagnosed with MCD. Among atypical features, hematuria and steroid-resistance would be the most probable indicators for a diagnosis other than MCD. Even in patients with SRNS, long-term methylprednisolone pulse therapy may result in a good remission rate.