Is typing for HLA class II alleles beneficial in Indian children with idiopathic nephrotic syndrome?

Abstract

This study was conducted to test the hypothesis that analysis of HLA class II type alleles will give important information on the prognosis of NS in children. We prospectively studied 100 consecutive children with idiopathic nephrotic syndrome and 202 controls belonging to the same geoethnic background. Typing for HLA Class II alleles at DR and DQ locus was carried out by using SSP (sequence specific oligonucleotides based method). In our study children were more likely to have nephrotic syndrome if the allele DQ-β1*020X was present as compared to controls. On the other hand, DR-β1*1001, DR-β1*130X and DQ-β1*030X were significantly lower among patients and likely to be protective. On analysing the different steroid response categories, we observed that the allele DQ-β1*020X was significantly higher in infrequent relapsers (IFR) with a high etiological fraction of 0.714. Children were more likely to be steroid resistant if the allele DR-β1*150X was present and the etiological fraction was high (0.754). The allele DQ-β1*030X was significantly lower in steroid resistant patients (p=0.019, RR=0.1819, 95% CI=0.04430–0.7471) and likely to be protective. On analysing the haplotype distribution, we observed that occurrence of DR-β1*070X-DQ-β1*020X haplotype was significantly more common among patients with steroid sensitive nephrotic syndrome (23.94%) as compared to controls (12.5%) (p=0.01). In the steroid resistant group we observed that the haplotype DR-β1*150X-DQ-β1*060X was significantly more frequent as compared to steroid sensitive patients as well as controls p=0.01. We conclude that HLA typing in Indian children with NS helps to predict relapse frequency and steroid resistance.