AB0314 VIRAL HEPATITIS B REACTIVATION UNDER BIOLOGICAL THERAPY: SCREENING AND PREVENTION MODALITIES IN RHEUMATIC AND INFLAMMATORY BOWEL DISEASE PATIENTS
Authors: S. Nsibi, R. Ennaifer, B. Bouchabou, K. Ben Abdelghani, A. Fazaa, H. Ben Nejma, A. Laatar
Journal: Annals of the Rheumatic Diseases (2020)

Background: Viral hepatitis B reactivation (VHBr) is a serious complication of immunomodulatory therapy and in particular biological therapy (BT), which can be life-threatening, whence the adoption by societies of screening and prevention strategies based on the risk of VHBr which depends on serological status and the treatment used. Objectives: The objective of our study was to determine the modalities of HBV screening, to describe the prevalence of HBV infection in this group of patients, and to evaluate the VHBr prevention strategies adopted in our country. Methods: This was a retrospective, 8-year [2011-2018], single-centre, descriptive, retrospective study conducted in two departments: Rheumatology and Hepato-Gastroenterology. Patients under BT were included. Records with missing data were excluded. The modalities of screening and prevention of VHBr were determined and the prevalence of HBV markers was investigated. Results: One hundred patients were included: 85 followed up for chronic inflammatory rheumatic disease: rheumatoid arthritis (n=40), ankylosing spondylitis (n=41), juvenile idiopathic arthritis (n=4) and 15 patients followed up for inflammatory bowel disease (11 Crohn’s disease and 4 ulcerative colitis). The mean age was 44 years with a predominance of females (59%). The BTs prescribed were: anti-TNFα, anti-IL6 and antiCD20 in 83%, 11% and 7% respectively. HBV screening was done in 89% of cases: HBsAg was tested in 89%, anti-HBc in 64% and anti-HBs in 43%. Complete B serology (HBsAg, anti-HBc and anti-HBs) was performed in 40%. One patient had chronic hepatitis B on Entecavir for 3 years before starting anti-CD20 (HBsAg(+),anti-HBc(+)). A previous contact with HBV as evidenced by isolated anti-HBs(+) positivity was noted in 13 patients (20%). A negative B serology was noted in 30 patients (30%). The vaccination rate was 10%. Prophylaxis with Entecavir was indicated in 2 patients at high risk of viral B reactivation (candidates for anti-CD20 therapy and having anti-HBc(+) with undetectable viral load).One patient at moderate risk of reactivation (candidate for anti-TNF therapy and having anti-HBc(+)) was placed on Lamivudine for prophylaxis. Pre-emptive therapy based on monitoring of alanine aminotransferase (ALT) and HBV DNA levels every 1 to 3 months was indicated in 10 patients (with anti-HBc (+) and candidates for BT other than anti-CD20) but correctly applied in only 2 patients (20%). The remaining eight patients were monitored only for ALT levels. No cases of viral reactivation B were objectified. Conclusion: In our study, viral hepatitis B screening was done correctly in 40% of the cases. The rate of VHB vaccination was low (10%) despite the low cost of the vaccine. Prophylactic and pre-emptive treatment for viral reactivation were correctly applied in 100 and 20% of cases respectively. This underlines the difficulties encountered in applying pre-emptive treatment when access to HBV DNA level determination is limited and warrants more vigilance prior to the prescription of BT. Disclosure of Interests: None declared