AUTHOR=Ye Junna , Xie Peilin , Zhou Zhuochao , Sun Yue , Wang Fan , You Yijun , Teng Jialin , Yang Chengde , Zhang Xinxin , Han Yue 

TITLE=Protective Role of Rheumatic Diseases Against Hepatitis B Virus Infection and Human Leukocyte Antigen B27 Highlighted

JOURNAL=Frontiers in Medicine

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2022.814423

DOI=10.3389/fmed.2022.814423

ISSN=2296-858X

ABSTRACT=Background:
By determining the Hepatitis B Virus (HBV) surface antigen (HBsAg) positive rate post-exposure and HBV specific antigen/antibody (Ag/Ab) level in patients with rheumatic diseases, we aimed at exploring the rheumatic link to HBV control.
Methods:
Patients who underwent HBV screening in Ruijin Hospital from 2020 to 2021 were enrolled for the exposure rate estimation. Among antibody to HBV core antigen (HBcAb) positive patients, we adopted propensity score matching (PSM) to study the impact of rheumatism on HBsAg seroprevalence after exposure. A second PSM evaluated the Ag/Ab differences. We also had HBsAg prevalence in Human leukocyte antigen B2 (HLA-B27) tested patients studied.
Results:
With 33989 screened patients, exposure rates remained comparable between rheumatic and non-rheumatic patients: 48.94% vs. 49.86%. PSM first yielded 2618 balanced pairs. We observed significantly fewer patients with rheumatic diseases in HBsAg positive cases than negative ones (p<0.001). In the second round PSM matched 279 pairs, HBsAg (p<0.001) and HBeAg (p<0.05) positivity rates were significantly lower in rheumatic patients, whereas HBsAb positivity rate (p<0.001) and level (p<0.01) were significantly higher. Though the value of HBcAb was overall significantly lower (p<0.001) within the realm of rheumatic diseases, patients with ankylosing spondylitis (AS) demonstrated a significantly higher value than other rheumatic diseases. We saw significantly fewer HBV infections in HLA-B27 positive subjects than negative ones (p<0.001).
Conclusion: 
In this propensity score-matched study, rheumatic patients had an advantage in HBV control. In rheumatic patients, HBcAb levels, together with the beneficial role of HLA-B27, were highlighted.