Hepatitis B and C virus infection in Crohn's disease

Patients with Crohn's disease (CD) are at higher risk of hepatitis C (HCV) and B virus (HBV) infection, because of surgical and/or endoscopic procedur es. However, the prevalence of HCV and HBV infection in CD is unknown. This issue may be relevant because of the growing use of immunomodulatory drugs in CD. The purpose of this study was to assess, in a multicenter study, th e prevalence and risk factors of HCV and HBV infection in CD. The effect of immunomodulatory drugs for CD on the clinical course of hepatitis virus in fections and of interferon-alpha (IFN-alpha) on the course of CD was examin ed in a small number of patients. Sera from 332 patients with CD and 374 co ntrol subjects (C) were tested for the following: hepatitis B surface antig en (HBsAg), hepatitis B surface antibody (HBsAb), HBcAb, HBeAg, HBeAb, anti -HCV, and HCV-RNA, An additional 162 patients with ulcerative colitis (UC) were tested as a disease control group. Risk factors were assessed by multi variate statistical analysis. Infection by either HCV or HBV was detected i n 24.7% of patients with CD. In the age groups younger than 50 years, HCV p revalence was higher in CD than in C (p = 0.01). HCV infection in CD was as sociated with surgery (OR 1.71; 95% CI 1.00-2.93; p = 0.04), blood transfus ions (OR 3.39; 95% CI 1.04-11.04; p = 0.04), and age (OR 2.3; 95% CI 1.61-3 .56; p < 0.001). The event CD-related surgery appeared to be the main risk factor for HCV infection in CD. HCV prevalence was higher in CD (7.4%) than in UC (0.6%) (p = 0.001). HBcAb positivity was higher in CD (10.9%) and UC (11.5%) than in C (5.1%) (CD vs. C: p = 0.016; UC vs. C: p = 0.02), associ ated with age (OR 2.08; 95% CI 1.37-3.17; p = 0.001) and female gender (OR 2.68; 95% Cl 1.37-3.17; p = 0.001) in CD and to UC duration (OR 1.20; 95% C l 1.06-1.36; p = 0.002). Immunomodulatory drugs did not influence the cours e of HBV or HCV infection in seven patients with CD, and IFN-alpha for chro nic hepatitis C did not affect CD activity in six patients with CD. It is c oncluded that HBV prevalence is higher in CD than in C at all ages, whereas HCV prevalence is increased in young patients with CD, because of a greate r need for surgery. The higher HCV (but not HBV) prevalence in CD than in U C suggests that the host immune response may influence the risk of HCV infe ction. Although a relatively high proportion of patients with CD showed HBV and/or HCV infections, this should not influence treatment strategies for CD.