P279. A report on the prevalence and reactivation rate of hepatitis B virus in patients with inflammatory bowel disease in Japan
Y. Yokoyama1, M. Kawai1, K. Kamikozuru1, K. Nogami1, M. Nakamura1, M. Iimuro1, N. Hida1, H. Miwa2, S. Nakamura1, 1Hyogo College of Medicine, Internal Medicine, Division of Lower Gastroenterology, Nishinomiya, Japan, 2Hyogo College of Medicine, Internal Medicine, Division of Upper Gastroenterology, Nishinomiya, Japan
Hepatitis B virus (HBV) can be a serious co-morbidity in patients with inflammatory bowel disease (IBD) as immunosuppressive therapy required to treat IBD may promote HBV reactivation. Further, in Japan, HBV infection remains prevalent at about 24.7%, and therefore, better understanding of clinical features of HBV infected patients is essential. Further, the prevalence of HBV infection in patients with IBD and the risk of reactivation related to medication for IBD are largely unknown. The present investigation was to better understand the prevalence and reactivation rate of HBV in IBD patients.
In a retrospective and single centre setting, we investigated the frequencies of hepatitis B surface antigen (HBsAg)-positive, and hepatitis B surface antibody (HBsAb)-positive or hepatitis B core antibody (HBcAb)-positive detection among IBD patients who were treated at our IBD unit over several years. Liver dysfunction related to HBV reactivation was defined as an increase in serum alanine aminotransferase and an increase of more than 1 log copies/ml of HBV DNA levels.
Of 236 patients (ulcerative colitis: UC, 117; Crohn's disease: CD, 119) treated in our hospital between 2008 and 2012, 11 patients (4.7%) were HBsAg-positive (UC, 5; CD, 6), and 38 patients (16.1%) were HBcAb or HBsAb-positive (UC, 19; CD, 19). Mesalamine (n = 43), corticosteroid (n = 19), adsorptive granulocyte and monocyte apheresis (GMA, n = 18), elemental diet (n = 17), anti-tumour necrosis factor-α antibody (n = 15), and thiopurines (n = 9) were the treatment interventions patients were receiving for active IBD at the time of HBV diagnosis. Liver dysfunction was found in 7 patients (14.3%), the causes were non-alcholic steatohepatitis and side effects of thiopurines in 6 patients. However, only one HBsAg-positive CD patient showed HBV reactivation. This patient had been treated with adalimumab for one year without anti-viral medications (Entecavir). After taking Entecavir, the patient's liver dysfunction improved. No HBV reactivation was found among the HBcAb or HBsAb-positive patients.
Hitherto aggressive immunosuppressive therapy required to treat IBD has been suspected to cause HBV reactivation, and complicating the patients' IBD. Accordingly, acquiring knowledge on the clinical features of HBV infection is a clinically relevant undertaking. In this study involving 236 IBD patients, the prevalence of HBV was modest in terms of HBsAg, but relatively high in terms of HBsAb or HBcAb. Surprisingly the HBV reactivation occurred only in 1 case in spite of the ongoing medications. Nonetheless, anti-viral intervention should be considered before administering adalimumab in patients with HBV.