Evaluation of the Indications of Renal Biopsy in Children with Primary Nephrotic Syndrome

Lee, Seung Joo

Abstract

PURPOSE
Percutaneous renal biopsy in children with primary nephrotic syndrome(NS) contributed to establish the renal pathology and clinicopathological correlation. The most common minimal change lesion(MCL) was steroid sensitive and could be predicted by clinical and laboratory findings. It was uniformly agreed that most nephrotic children who were predicted as MCL, should receive an 8 week course of prednisolone before considering renal biopsy. Early indications of renal biopsy has been those nephrotic children with the age below 1 year and above 8 years, hypertension, hematuria, low serum C3, renal insufficiency which are not compatible with MCL. Late indications has been frequent relapser(FR), steroid dependent(SDNS) and steroid resistant nephrotic syndrome(SRNS). The indications have been challenging recently and we tried to evaluate the commonly recommended indications.
METHODS
Clinical, laboratory, pathologic findings and therapeutic responses were compared in 81 children with primary nephrotic syndrome who had renal biopses beteen 1984 and 1996.
RESULTS
1) Among 11 children with the age indication, MCLs were diagosed in 9(81.8%), mesangial proliferative glomerulonephritis(MsPGN) in 1(9.1%) and membranous nephropathy(MGN) in 1(9.1%). 2) Among 4 children with microscopic hematuria, MCLs were diagosed in 3(75.0%), MsPGN in 1(25.01%). In 13 children with hypertension, macrohematuria, azotemia and low serum C3, focal segmental glomerulosclerosis(FSGS), membrano-proliferative glomerulonephritis(MPGN) and IgA nephropathy(IgA) were frequently diagnosed instead of MCL. 3) All 5(100%) frequent relapsers were diagnosed as MCLS Among 30 children with the indication of SDNS, MCLs were diagosed in 28(93.3%), MsPGN in 2(6.7%) 4) Among 18 children with the indication of SRNS, MCLs were diagosed in 6(33.3%), MsPGN in 6(33.3%), FSGS in 6(33.3%) 5) The probability to diagnose MCL was 81.8%(9/11) in age indication, 75.0%(3/4) in microscopic hematuria, 100%(5/5) in FR and 93.3%(28/30) in SDNS. 6) The response rate to standard steroid treatment were 81.8%(9/11) in age indication 75.0%(3/4) in microscopic hematuria, 100%(5/5) in FR and 96.7%(29/30) in SDNS.
CONCLUSIONS
Among the commmon indications of renal biopsy in children with primary nephrotic syndrome, age, microscopic hematuria, frequent relapser and steroid dependant should be reevauated to reduce the unnecessary renal biopsy.