A study of association between regulatory polymorphism in the IL-10 gene promoter region and acute viral hepatitis, and acute liver failure.

BACKGROUND: The level of inflammatory cytokine Interleukin (IL)-10 is increased in patients infected with hepatitis-related acute liver failure (ALF), and this was thought to be because of the regulatory polymorphism in the IL-10 gene promoter region. The present study was designed to analyze the possible association between IL-10 gene promoter polymorphism and acute viral hepatitis (AVH), and ALF. An attempt was made to quantify IL-10 levels at admission, during the hospital stay, and at the final outcome to study its relationship with liver injury among patients with AVH, ALF, and controls.

METHODS: The study included 40 patients each with ALF and AVH. IL-10 gene promoter polymorphism was detected by the PCR-RFLP method. Quantification of IL-10 was done using commercially available ELISA kits.

RESULTS: The individuals with -592 AC, -819 TC, -1082 AA genotypes were found to have a significantly higher risk of ALF whereas those with -592 AA and - 819 CC polymorphism were found to be less susceptible. Individuals with - 819 CC were found to be more susceptible to AVH while those with -592 AA and -819 TT were less susceptible as compared to controls. Mean serum IL-10 at admission was significantly elevated in patients with ALF (38.4±11.3 pg/mL) as compared to patients with AVH (16.7±5.4 pg/mL) and control population (8.3±3.6 pg/mL, p < 0.05).

CONCLUSION: Regulatory polymorphism in the IL-10 gene promoter has a possible and significant association with severity and outcome in patients with AVH and ALF. Raised levels of IL-10 could be predictive of prognosis in patients with ALF.