BACKGROUND: Data on the prevalence of hepatitis C in patients with inflammatory bowel diseases (IBD) are limited and conflicting. This study was to assess the prevalence of hepatitis C virus (HCV) infection in IBD patients and to define the clinical and immunologic profile of IBD associated with HCV infection. METHODS: Ten patients (seven females and three males) with IBD and HCV infection were consecutively recruited in our department between June 2005 and May 2010. We analyzed the clinical and serologic description of all patients. RESULTS: The mean age of the 10 patients was 41 years and the median disease duration was 7 years. With present and/or past HCV infection, the patients had clinical manifestations and were positive for endoscopic study or histological test. Compared with the HCV-negative IBD group, the HCV-positive IBD group have a higher positive rate of autoantibodies (antinuclear antibodies, antieutrophil cytoplasmic antibody, and anti-SSa/SSb). In the HCV- positive group, 8 patients were positive for p-antieutrophil cytoplasmic antibody, 4 positive for antinuclear antibodies, and 3 positive for anti-SSa/SSb. Four patients had an elevated level of transaminase (alanine transminase, and aspartate transminase). CONCLUSIONS: HCV positive in IBD may induce autoantibodies (antinuclear antibodies, antieutrophil cytoplasmic antibody, anti-SSa/SSb) and damage of liver function. In managing IBD patients, physicians should be aware of screening of HCV and prescribe antiviral treatment. BACKGROUND: Data on the prevalence of hepatitis C in patients with inflammatory bowel diseases (IBD) are limited and conflicting. This study was to assess the prevalence of hepatitis C virus (HCV) infection in IBD patients and to define the clinical and immunologic profile of METHODS: Ten patients (seven females and three males) with IBD and HCV infection were consecutively recruited in our department between June 2005 and May 2010. RESULTS: Clinical and serologic description of all patients. RESULTS: The mean age of the 10 patients was 41 years and the median disease duration was 7 years. With present and / or past HCV infection, the patients had clinical manifestations and were positive for endoscopic studies or histological tests. Compared with the HCV-negative IBD group, the HCV-positive IBD group has a higher positive rate of autoantibodies (antinuclear antibodies, antieutrophil cytoplasmic antibody, and anti-SSa / SSb). In the HCV-positive gro up of 8 patients were positive for p-antieutrophil cytoplasmic antibody, 4 positive for antinuclear antibodies and 3 positive for anti-SSa / SSb. Four patients had an elevated level of transaminase (alanine transminase, and aspartate transminase). CONCLUSIONS: HCV positive in IBD may induce autoantibodies (antinuclear antibodies, antieutrophil cytoplasmic antibody, anti-SSa / SSb) and damage of liver function. In managing IBD patients, physicians should be aware of screening of HCV and prescribe antiviral treatment.