Hepatitis B virus coinfection in patients treated for chronic hepatitis C: clinical characteristics, risk of reactivation with long-term follow-up, and effectiveness of antiviral therapy.

Dorota Zarębska-Michaluk, Michał Brzdęk, Piotr Rzymski, Krystyna Dobrowolska, Robert Flisiak

Hepatitis B virus (HBV) and hepatitis C virus (HCV) share a similar transmission route, increasing coinfection odds, which worsens clinical outcomes.  Objectives: Therefore it is pivotal to study coinfected patients undergoing HCV treatment with direct-acting antivirals (DAAs) to understand their characteristics, risk of HBV reactivation, and effectiveness of therapy.  Patients and methods: The present research included the complex analysis of 1118 patients with chronic HCV infection, divided into three subgroups based on HBV status.  Results: We documented that 0.7% of the analyzed population was positive for hepatitis B virus surface antigen (HBsAg), while 14.3% had evidence of a past HBV infection. Patients without HBV coinfection were less burdened with comorbidities and were mostly treatment-naïve, while patients suffering from coinfection were younger and more likely to have a history of previous therapy. Infection with HCV genotype 3 was more common among HBsAg-positive patients than in other studied groups. Response to DAA therapy was comparable between groups, and most patients completed the course of treatment as planned. Only three cases of HBV reactivation were observed, all of which achieved sustained virologic response after DAAs therapy. Two were women on immunosuppressants with anti-hepatitis B core (anti-HBc) positive antibodies; the third patient was male and HBsAg-positive. These patients remained under long-term follow-up. Neither the presence of HBV markers nor the reactivation during DAA treatment reduced the effectiveness of the therapy. The present study's findings are important for future recommendations and guidelines on managing HBV/HCV coinfection.