Comparing NPHS2 and WT1 Mutations in Children with Nephrotic Syndrome

Document Type : Original Article (s)

Authors

1 Associate Professor, Department of Pediatrics, School of Medicine AND Child Growth and Development Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

2 Student of Medicine, School of Medicine AND Student Research Committee, Isfahan University of Medical Sciences, Isfahan, Iran

3 Assistant Professor, Department of Pediatrics, School of Medicine AND Child Growth and Development Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

Abstract

Background: Nephrotic syndrome (NS) is a common type of kidney disease in children characterized by massive proteinuria, hypoalbuminemia and edema. Response to therapy can be affected by factors like pathologic views, genetic and clinical manifestations. The incidence of genetic mutations is different in variant geographic locations and races. Response to nephrotic syndrome treatment can be influenced by some mutations in WT1 and NPHS2 genes.Methods: 49 children suffering from nephrotic syndrome participated in two groups of steroid-sensitive (n = 14) and steroid-resistant (n = 35) nephrotic syndrome. Mutations in WT1 and NPHS2 genes analyzed by polymerase chain reaction (PCR) and direct sequencing. Clinical and pathological reviews were done too.Findings: There was a significant relationship between both primary creatinine and hypertension in the first visit and resistance to therapy. Pthological views of focal segmental glomerulosclerosis (FSGS), glomerular fibrosis, and glomerular sclerosis were significantly related to steroid resistance group (P < 0.001). Genetic analysis for mutations of WT1 and NPHS2 genes among 29 children with idiopathic nephrotic syndrome showed 2 and 5 different mutations in WT1 and NPHS2 genes, respectively. All of the mutations were seen in steroid-resistant group.Conclusion: This study demonstrates the importance of WT1 and NPHS2 analysis and pathological study in Iranian children with nephrotic syndrome.

Keywords


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