title: Epidemiological, clinical and histological characteristics of HBV/HDV co-infection: a retrospective cross-sectional study in Guangdong, China.
abstract: BACKGROUND
  The epidemiology of hepatitis D virus (HDV) in China is fairly unknown. The mechanisms whereby HDV leads to accelerated liver disease in hepatitis B virus (HBV)/HDV co-infected patients and the histological characteristics of chronic hepatitis D (CHD) patients need further investigation.
  
  
  METHODS
  The prevalence of HDV was retrospectively evaluated in all consecutive hospitalized patients with chronic HBV infection from May 2005 to October 2011. HBV/HDV co-infected patients and HBV mono-infected patients were compared clinically and histologically. Significant histological abnormality was defined as significant necroinflammation (grade ≥A2) and/or significant fibrosis (stage ≥ F2).
  
  
  RESULTS
  6.5% of patients (426/6604) tested positive for IgM anti-HDV. HDV was more common in patients over 50 years old than those under 50 (11.7% vs. 5.1%, P<0.001). HBV/HDV co-infected patients had higher frequencies of end-stage liver disease (ESLD) than HBV mono-infected patients, and HDV co-infection was an independent risk factor for ESLD (OR: 1.428, 95%CI: 1.116-1.827; P = 0.005). The HBV DNA levels in the HBV/HDV group were significantly lower than the HBV group in chronic hepatitis patients (median: 6.50 log10copies/mL vs 6.80 log10copies/mL, P = 0.003), but higher than the HBV group in ESLD patients (median: 5.73 log10copies/mL vs 5.16 log10copies/mL, P<0.001). When stratified by alanine aminotransferase (ALT) level, 46.7%, 56.5% and 80.5% of CHD patients had significant necroinflammation and 86.7%, 87.0% and 90.3% had significant fibrosis with ALT 1-2×upper limit normal (ULN), 2-5×ULN and>5×ULN respectively.
  
  
  CONCLUSIONS
  The prevalence of HDV is not low in patients with chronic HBV infection. HDV may contribute to progression to ESLD through late-phase HBV DNA reactivation.
authors.affiliation: Department of Infectious Disease, Guangzhou No. 8 People's Hospital, Guangzhou Medical University, Guangzhou, China.
authors.forename: Baolin
authors.initials: B
authors.lastname: Liao
authors.affiliation: Department of Infectious Disease, Guangzhou No. 8 People's Hospital, Guangzhou Medical University, Guangzhou, China.
authors.forename: Fuchun
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Department of Third Internal Medicine, Yuexiu District Traditional Chinese Medicine Hospital, Guangzhou, China.
authors.forename: Siwei
authors.initials: S
authors.lastname: Lin
authors.affiliation: Department of Infectious Disease, Guangzhou No. 8 People's Hospital, Guangzhou Medical University, Guangzhou, China.
authors.forename: Haolan
authors.initials: H
authors.lastname: He
authors.affiliation: Hepatology Unit and Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Infectious Disease, Guangzhou No. 8 People's Hospital, Guangzhou Medical University, Guangzhou, China.
authors.forename: Jiansheng
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Hepatology Unit and Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Infectious Disease, Guangzhou No. 8 People's Hospital, Guangzhou Medical University, Guangzhou, China.
authors.forename: Junqing
authors.initials: J
authors.lastname: Yi
authors.affiliation: Hepatology Unit and Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Yunqing
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Infectious Disease, Guangzhou No. 8 People's Hospital, Guangzhou Medical University, Guangzhou, China.
authors.forename: Huiyuan
authors.initials: H
authors.lastname: Liu
authors.affiliation: Hepatology Unit and Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Zhanhui
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Infectious Disease, Guangzhou No. 8 People's Hospital, Guangzhou Medical University, Guangzhou, China.
authors.forename: Weiping
authors.initials: W
authors.lastname: Cai
mesh_terms: D000328:Adult; D000368:Aged; D002681:China / Q000453:epidemiology; D060085:Coinfection / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D004279:DNA, Viral / Q000235:genetics; D005260:Female; D005500:Follow-Up Studies; D006508:Hepatitis Antibodies / Q000097:blood; D006509:Hepatitis B / Q000453:epidemiology* / Q000821:virology*; D006515:Hepatitis B virus / Q000235:genetics / Q000302:isolation & purification*; D003699:Hepatitis D / Q000453:epidemiology* / Q000821:virology*; D003698:Hepatitis Delta Virus / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008111:Liver Function Tests; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011379:Prognosis; D012189:Retrospective Studies; D019562:Viral Load; D055815:Young Adult
chemical_list: D004279:DNA, Viral; D006508:Hepatitis Antibodies