Association between interleukin-22 genetic polymorphisms and the prognosis of hepatitis B virus related acute-on-chronic liver failure

Abstract

Objective To investigate the association between interleukin-22 (IL-22) single nucleotide polymorphisms (SNPs) and the prognosis of hepatitis B virus related acute-on-chronic liver failure (HBV-ACLF). Methods The patients with HBV-ACLF from the First Affiliated Hospital of Fujian Medical University were retrospectively studied. Seven SNP genotypes of IL-22 gene, including rs2227478, rs2227491, rs1179251, rs1179249, rs2227473, rs2227484, and rs11611206, were detected using imLDR™ multiple SNP typing kit and the distribution features of SNP genotypes were described. The relationship between the distribution of SNP genotypes and alleles and the prognosis of ACLF was analyzed. Comparison of genotypes and allele frequencies between groups were performed by chi-square test of R×C table or Fisher's exact tests. Binary logistic regression analysis was used to analyze whether IL-22 gene polymorphisms was an independent prognostic factor for patients with ACLF. Results A total of 122 patients with HBV-ACLF were included in this study. Ninety-two (75.1%) were male and 30 (24.59%) were female. Patients were stratified as survival group (90 cases) and non-survival group (32 cases) according to the Results of three months follow-up. The genotype distribution of rs2227484 of IL-22 gene was significantly different between the two groups (χ2=6.128, P=0.033). The A allele frequency in the non-survival group (15.6%) was significantly higher than that in the survival group (5.6%) with statistically significance (OR=0.318, 95% CI=0.126-0.804, P=0.012). There was no significant difference in the other six SNP genotypes of IL-22 gene between the two groups (all P >0.05). However, binary logistic regression showed that rs2227484 of IL-22 gene was not an independent risk factor for the short-term mortality in HBV-ACLF patients (adjusted OR=3.102, 95%CI: 0.939-10.250, P=0.063). Conclusions The A allele and AA genotype of rs2227484 of IL-22 gene may be associated with a short-term prognosis in patients with HBV-ACLF. Key words: Hepatitis B virus; Polymorphism, genetic; Interleukin-22; Acute-on-chronic liver failure