TREATMENT with interferon and ribavirin in patients with …….chronic hepatitis C (CHC) is the most common therapy although it is accompanied by multiple side effects. Bacterial infection represents the most common side effect. The present study aims to analyze the relation between bacterial infection in patients with CHC, interferon treatment and virulence factors of isolated bacteria. Out of 212 immunocompromised patients with hepatitis C hospitalized were studied for bacterial infection, the median age of patients was 50 years (range 23-83 y) of which 132 male (62.3%) and 80 females (37.7%). 149 patients have a bacterial infection while 63 patients are negative for bacterial infection. The collected data obtained from patients showed that 92 patients (43.5 %) not treated with interferon and 120 (56.6%) treated with different doses of the interferon and ribavirin, Our results showed that the bacterial infection represents 90.8 % of patients who were treated with interferon while patients who were not treated with the combined therapy showed signs of infections of  43.5 %. E. coli being the most frequent pathogen (25%) followed by Acinetobacter baumannii (13.8 %). The strains were confirmed by Biolog Microlog 34.20 system. The development of bacterial infection in patients treated with interferon associated with hematological complications as anemia (85.4 %), neutropenia (94.5 %) and thrombocytopenia (100 %).Patients with CHC undergoing treatment with interferon and ribavirin have increased the risk of developing a bacterial infection as a result of bone marrow suppression.