FRI0155 Prevalence of hbv infection and risk of reactivation on biologic treatment: a population-based observational study of rheumatoid arthritis subjects in a northern italy area
Authors: M Meroni, L Sangiovanni, E Lupi, S Fagiuoli, M Limonta
Journal: Annals of the Rheumatic Diseases (2017)

<h3>Background</h3> The introduction of biologic agent9s treatment in rheumatic diseases dramatically changed their outcome, but raised some concerns about infections recrudescence. Due to the prevalence of hepatitis B virus (HBV) among Italian general population (2–6%), the possibility of a disease reactivation in case of an immunosuppressive treatment has to be considered. <h3>Objectives</h3> Aim of this prospective, population-based observational study was to assess the prevalence of HBV (both in chronic carriers and recativated) rheumatoid arthritis (RA) patients in our setting; to verify if these findings were in line to the Italian and European-reported data; finally, to evaluate the final outcome of HBV RA subjects. <h3>Methods</h3> We enrolled the totality of RA patients treated by biologics and, therefore, consulting our Unit at least every 12 weeks, from December 2015 to January 2017. According to the current (ACR/EULAR and AASLD) guidelines, every subject was screened for HBV before starting biologic treatment. Descriptive statistics was performed. Acute infection; previous (resolved) infection; inactive and active carrier; and vaccine-immunized subjects were defined according to Tab. I. <h3>Results</h3> A totality of 265 RA patients (female 56.3%; male 43.7%; mean age 36+/-20 years) underwent biologic treatment after succeeding the screening (HBsAg+ subjects were excluded). The huge majority of them (82%) was treated by TNF-alpha inhibitors (TNFi), since the remaining received biologic agents with different mechanisms of action. We overall detected 33 (12.5%) inactive carriers, for whom HBsAg and HBV DNA periodical monitoring was suggested; in 3 of them (1.1% of the study population), HBV DNA became detectable, with a low viral load (&lt;2000 UI/ml): they prosecute the biologic therapy after the introduction of the standard prophylaxis (lamivudine 100 mg daily) and a more strictly (periodic liver enzymes and liver ETG evaluation) monitoring. In occasion of the screening, we observed 6 (2.3%) HBV-immunized (due to vaccine) and 6 (2.3%) previously infected (HBcAb+) patients: for the first ones no action is required, since the latter were put on standard prophylaxis before undergoing biologic agent and monitored. One of them (0.38%) developed, after 6 months of treatment, HBV reactivation with high-level (&gt;2000 UI/ml) detectable DNA and liver enzymes elevation (&gt;normality x3). She was therefore stopped from receiving biologic agent and put on entecavir 1 mg daily. <h3>Conclusions</h3> Our prospective, population-based observational study, performed in a first-level referring Hospital in a highly populated area, suggests some considerations. In a way, our data reported a significantly higher prevalence of HBV infection "contact" among our RA population, in comparison to the general one (p&lt;0.05). This issue has previously been reported and could be justified but the generally higher HBV diffusion in certain area (i.e., Italy); by the age/ethnicity of the sample; and, finally, by the bias consisting in an extensive screening of these patients. On the other hand, our experience suggests that a tight monitoring of parameters predicting infectious flare should lead to a prompt diagnosis and a lower number of complications for these peculiar patients, as observed in our population. <h3>Disclosure of Interest</h3> None declared