This study aimed to investigate the incidence of bacterial infection in chronic hepatitis C virus (HCV) patients with cirrhosis and association between toll-like receptor 4 D299G gene polymorphism and Gram-negative bacterial infections in the patients. 100 HCV cirrhotic patients with ascites and 20 age- and sex-matched healthy subjects as control were included. Conventional culture methods were used to identify the causative organism of infection. Toll-like receptor 4 D299G polymorphism was detected by PCR- RFLP (polymerase chain reaction – restriction fragment length polymorphism). Patients were divided into: Group I: 100 HCV cirrhotic patients with ascites. They were subdivided into: Group I (a): Patients with Toll-like receptor 4 D299G polymorphism, Group I (b): Patients without polymorphism. Group II (control): 20 healthy subjects. This study showed significant higher incidence of infections in cirrhotic patients with Toll-like receptor 4 D299G polymorphism which play a role in the development of bacterial infection in cirrhotic patients that makes down-regulation of TLR4 response one of the immune mechanisms predisposed to Gram negative bacterial infection in cirrhotic patients.

Keywords: TLR-4 gene polymorphism, cirrhosis, bacterial infection.