HLA-DRB1 alleles in Egyptian children with steroid-sensitive nephrotic syndrome: association with outcome

ABSTRACT

To investigate whether polymorphic HLA-DRB1 alleles are significantly associated with outcome in Egyptian children with steroid-sensitive nephrotic syndrome [SSNS]. Cross-sectional study. Among attendants of Pediatric Nephrology Outpatient Clinic, 54 unrelated children with SSNS were enrolled. They included 32 males and 22 females, their ages ranged from 1.8 to 14 years. According to response to standardized prednisone therapy, patients were categorized into two different outcome groups non-relapsing or Infrequently relapsing [NR/IR] group [n = 24], and Frequently relapsing [FR] group [n = 30]. Among FR patients, 24 were treated with alkylating agents, and according to their responses, they were categorized into two different outcome groups active disease outcome group [n = 15] and long-term remission outcome group [n = 9]. HLA-DRB1 alleles typing was done using the DNA polymerase chain-reverse hybridization technique. The results of present study showed that [I]. DRB101 alleles showed significant positive association with NR/IR outcome [relative risk [RR] = 45, 95% confidence interval [95% Cl] = 19.1-105.7, Phi-coefficient [delta = + 0.74, P<0.00001, correctedP [Pb] <0.001]; and significant negative association with FR outcome [RR = 0.03, 95% Cl = 0.01-0.09, delta = - 0.69, P <0.00001, Pb <0.001]; [II]. DRB10701/0301 alleles-heterozygosity showed significant positive association with FR outcome [RR = 72.25, 95% Cl = 30 -169.3, delta = + 0.89, P<0.00001, Pb <0.001]; and significant negative association with NR/IR group [RR = 0.01, 95% Cl = 0.004-0.02, delta = 0.93, P <0.00001, Pb <0.001]; [III]. DRB10701 allele showed significant positive association with active disease outcome after alkylating therapy [RR =111, 95% Cl = 47.2-260.8, delta = + 0.82, P <0.00001, Pb <0.001]; and significant negative association with long-term remission outcome [RR = 0.009, 95% Cl = 0.004-0.02, delta = - 0.82, P <0.00001, Pb <0.001]. The current data suggest that HLA-DRB1 alleles are significantly associated with outcome in Egyptian children with steroid-sensitive nephrotic syndrome. The present authors propose that new therapeutic trials in SSNS should take into account the HLA status of patients