Introduction: Hepatitis B reactivation and administration of prophylactic antiviral treatment are considered in patients with autoimmune inflammatory rheumatic diseases (AIIRD) undergoing immunosuppressive/immunomodulatory treatment. Data are more robust for rheumatoid arthritis patients receiving bDMARDs but are limited for other AIIRD and drug categories. Methods: Adult patients with AIIRD (inflammatory arthritis [IA] or connective tissue diseases [CTD]) and documented chronic or resolved HBV infection (defined as serum HBsAg positivity or anti-HBcAb positivity in the case of HBsAg non-detection respectively), followed-up in six rheumatology centers in Greece and Italy, were included. Data collected included demographic characteristics, AIIRD medications prior and after HBV screening [cs-DMARDs, (b-ts)- DMARDs, other immunosuppressants initiated and mean glucocorticoid dose], HBV prophylactic treatment, and possible HBV-reactivation (defined as increase in HBV-DNA or HBsAg seroconversion) within one year of HBV screening. Frequency of HBV reactivation and possible association with recorded parameters were examined. Results: During one year of follow-up, HBV reactivation occurred in 5.6% and 7.9% of IA and CTD patients, respectively. In patients with chronic hepatitis B, reactivation rates were 14.8% for IA and 22.2% for CTD, while in patients with resolved hepatitis B were 3.7% and 6%, respectively. In patients with resolved hepatitis B no association was found between HBV reactivation and antiviral prophylactic treatment, or the use of csDMARDs, bDMARDS, or other immunosuppressants. Conclusion: The risk of HBV reactivation was similar between IA and CTD patients and was significantly higher in chronic compared to resolved hepatitis B infection. For the latter, prophylactic treatment was not associated with lower reactivation risk.
