HBV reactivation in patients with HCV/HBV cirrhosis on treatment with direct‐acting antivirals

Anecdotal reports suggest that patients with chronic hepatitis C virus (HCV) hepatitis and overt or occult hepatitis B virus (HBV) coinfection may reactivate HBV when HCV is suppressed or cleared by direct‐acting antivirals (DAAs). We assessed the prevalence of overt or previous HBV coinfection and the risk of HBV reactivation in patients with HCV cirrhosis treated with DAAs. This was a retrospective cohort of 104 consecutive patients with HCV cirrhosis treated with DAAs. Serum HCV‐RNA and HBV‐DNA were tested at weeks 4, 8 and 12 of DAAs therapy and at week 12 of follow‐up. At the start of DAAs, eight patients (7.7%) were HBsAg positive/HBeAg negative with undetectable HBV‐DNA and low levels of quantitative HBsAg (four on nucleos(t)ide analogues NUCs] and four inactive carriers), 37 patients (35.6%) had markers of previous HBV infection (25 anti‐HBc positive, 12 anti‐HBc/anti‐HBs positive) and 59 (56.7%) had no evidence of HBV infection. Sixty‐seven patients (64.4%) were HCV‐RNA negative at week 4 and 98 (94.2%) achieved sustained virological response. All four HBsAg‐positive patients treated with NUCs remained HBV‐DNA negative, but three of four untreated patients showed an increase in HBV‐DNA of 2‐3 log without a biochemical flare and achieved HBV‐DNA suppression when given NUCs. During or after DAAs, by conventional assay, HBV‐DNA remained not detectable in all 37 anti‐HBc‐positive patients but in three of them (8.1%) HBV‐DNA became detectable with a highly sensitive PCR. HBV reactivation is likely to occur in untreated HBV/HCV‐coinfected cirrhotic patients when they undergo HCV treatment with DAAs. Pre‐emptive therapy with NUCs should be considered in this setting. Anti‐HBc‐positive patients rarely reactivate HBV without clinical or virological outcomes.