Mutation of NPHS1, NPHS2, WT1, LAMB2, COL4A5 and other genes in children with idiopathic steroid resistant nephrotic syndrome

Abstract

Background: Many children with idiopathic steroid resistant nephrotic syndrome have been reported worldwide due to mutation of NPHS1, NPHS2, WT1 and LAMB2 genes. This study aimed to determine the frequency of mutation of NPHS1, NPHS2, WT1, LAMB2, COL4A5 and other genes and their association with renal histopathological patterns of idiopathic steroid resistant nephrotic syndrome patients.

Methods: This cross-sectional study was conducted on 25 patients with idiopathic steroid resistant nephrotic aged 1-17 years in the Department of Paediatric Nephrology, Bangabandhu Sheikh Mujib Medical University, Bangladesh, from July 2017 to June 2018. Next Generation Sequencing and mutation analysis were performed after DNA extraction from patients' venous blood lymphocytes. Histopathological study of renal tissue was done among 17 patients.

Results:  A little more than half (56%) of the patients were male. The mean age at the initial attack of nephrotic syndrome was 94.2 months. They mostly had minimal change disease (41%) and IgA nephropathy (12%). One subject had the NPHS2 gene mutation, histopathologically diffuse mesangial proliferative glomerulonephritis, and clinically stage-4 chronic kidney disease. Another subject had the COL4A5 gene mutation and focal segmental glomerulosclerosis.  Both were male and had no familial renal disease, consanguinity, or hematuria.

Conclusion: Children with idiopathic steroid resistant nephrotic syndrome showed NPHS2 and COL4A5 gene mutations. Histopathologically, they showed diffuse mesangial proliferative glomerulonephritis and focal segmental glomerulosclerosis.