Clinicopathological Study about Childhood Primary Nephrotic Syndrome Resistant to 4-week Daily Steroid Therapy

Kim, Jung Sue; Ha, Il Soo; Cheong, Hae Il; Choi, Yong

Abstract

PURPOSE
Steroid-resistant nephrotic syndrome in children is difficult to manage and tends to progress to chronic renal failure. We studied clinicopathological correlations in primary nephrotic syndrome in children resistant to 4-week daily steroid therapy.
METHODS
Among children who had been admitted to Seoul National University Children's Hospital during the period between Oct. 1985 and Jul. 1995 and diagnosed as primary nephrotic syndrome, 87 patients were selected for this study. They showed poor response to 4-week daily steroid therapy either initially (initial nonresponder) or subsequently in the disease course (subsequent nonresponder). The medical records including renal pathologic findings were analyzed retrospectively.
RESULTS
The mean age at the onset of nephrotic syndrome was 7.3+/-4.1 years and male to female ratio was 62:25. Pathologically, 28 (32%) had minimal change lesion (MCL), 47 (54%) had focal segmental glomerulosclerosis (FSGS) and 12 (14%) had others. There were 15 (54%) initial nonresponders and 13 (46%) subsequent nonresponders in the MCL group, and there were 26 (55%) and 21 (45%), respectively, in the FSGS group. The incidence of hematuria was less frequent in the MCL group. The frequencies of hypertension and azotemia were not significantly different between in the MCL and the FSGS group. Among 10 patients with MCL in whom the steroid therapy were extended to 6 weeks, 3 patients responded subsequently. And 1 of 3 patients among the FSGS group responded to 8-week daily steroid therapy. The 2nd line drug therapy such as oral cyclophosphamide, intravenous pulsed methylprednisolone, enalapril, dipyridamole, etc. was tried in 26 patients with MCL and all 47 patients with FSGS. In the MCL group, 7 of 13 initial nonresponders and 9 of 13 subsequent nonresponders responded to these 2nd line drug therapies. In the FSGS group, 10 of 26 initial nonresponders and 11 of 21 subsequent nonresponders responded to these therapies. While only 1 subsequent nonresponder in the MCL group progressed to chronic renal failure, 9 initial and 4 subsequent nonresponders progressed in the FSGS group.
CONCLUSIONS
The FSGS group formed about a half and the MCL group formed about a third of steroid-resistant nephrotic syndrome in children. Although the response to 2nd line drug therapies was not different between 2 groups, the incidence of progression to chronic renal failure was significantly higher in the FSGS group.