1.Long-term real-world entecavir therapy in treatment-naïve hepatitis B patients: base-line hepatitis B virus DNA and hepatitis B surface antigen levels predict virologic response.
Ju Yeon CHO ; Won SOHN ; Dong Hyun SINN ; Geum Youn GWAK ; Yong Han PAIK ; Moon Seok CHOI ; Kwang Cheol KOH ; Seung Woon PAIK ; Byung Chul YOO ; Joon Hyeok LEE
The Korean Journal of Internal Medicine 2017;32(4):636-646
BACKGROUND/AIMS: Entecavir is a potent nucleoside analogue with high efficacy and barrier for resistance. We aimed to investigate the long-term efficacy and viral resistance rate of entecavir and explore the factors associated with virologic response, including quantitative hepatitis B surface antigen (qHBsAg) levels. METHODS: One thousand and nine treatment-naïve chronic hepatitis B (CHB) patients were evaluated for cumulative rates of virologic response, biochemical response, and entecavir mutations. The role of baseline qHBsAg for virologic response was assessed in 271 patients with qHBsAg prior to entecavir treatment. RESULTS: The median duration of entecavir treatment was 26.5 months. The cumulative rate of virologic response at years 1, 3, and 5 were 79.0%, 95.6%, and 99.4%, respectively. The cumulative rate of entecavir resistance was 1.0% and 2.1% in years 3 and 5. Multivariate analysis identified baseline hepatitis B e antigen (HBeAg) negative status (p < 0.001) and lower hepatitis B virus (HBV) DNA (p < 0.001) as predictors of virologic response. Lower qHBsAg was an independent predictor of virologic response in patients with baseline qHBsAg. There were no serious adverse events during treatment. CONCLUSIONS: Long-term entecavir treatment of nucleos(t)ide-naïve CHB patients was associated with an excellent virologic response and a low rate of entecavir-resistant mutations at 5 years. Baseline HBV DNA load, qHBsAg levels, and HBeAg status were predictors of virologic response during entecavir treatment.
DNA
;
Hepatitis B e Antigens
;
Hepatitis B Surface Antigens*
;
Hepatitis B virus*
;
Hepatitis B*
;
Hepatitis B, Chronic
;
Hepatitis*
;
Humans
;
Multivariate Analysis
2.Entecavir Resistance at rtS202, rtM250 May Cause Poor Viral Response to Tenofovir-based Rescue Therapy in Chronic Hepatitis B.
Sung Eun KIM ; Ji Won PARK ; Hyoung Su KIM ; Ki Tae SUK ; Myoung Kuk JANG ; Sang Hoon PARK ; Myung Seok LEE ; Dong Joon KIM ; Choong Kee PARK
Korean Journal of Medicine 2015;89(5):527-536
BACKGROUND/AIMS: Long-term use of nucleos(t)ide analogues (NA) may lead to genotypic and/or phenotypic resistance of the hepatitis B virus (HBV). We investigated the efficacy of tenofovir-based rescue therapy in chronic hepatitis B (CHB) patients with newly developed genotypic resistance to prior NAs or partial virologic response to sequential rescue therapies. METHODS: Fifty-four CHB patients were included retrospectively. The patients were treated with tenofovir alone or combined with lamivudine or entecavir. RESULTS: There were 26 forms of genotypic resistance at enrollment. The median amount of serum HBV-DNA was 18,438 IU/mL and 83% of samples were positive for hepatitis B e antigen (HBeAg). Serum HBV-DNA was undetectable in 50%, 61%, and 76% of the patients at 3, 6, and 12 months, respectively. In multivariate analysis, HBV-DNA < 20,000 IU/mL and negative HBeAg at baseline were independent predictors of negativity for serum HBV-DNA. Interestingly, the rtS202 mutation tended to be associated with an unfavorable response. Other clinical variables and viral resistance genotypes showed non-significant viral response. CONCLUSIONS: Lower serum HBV-DNA, negative HBeAg and lack of rtS202G mutations at baseline may predict a favorable response to tenofovir-based rescue therapies in CHB patients with newly developed genotypic resistance to prior NAs or a partial virologic response to sequential rescue therapies.
Drug Resistance
;
Genotype
;
Hepatitis B
;
Hepatitis B e Antigens
;
Hepatitis B virus
;
Hepatitis B, Chronic*
;
Hepatitis, Chronic*
;
Humans
;
Lamivudine
;
Multivariate Analysis
;
Retrospective Studies
;
Tenofovir
3.Emergence of YMDD motif mutant hepatitis B virus during long-term lamivudine therapy.
Jong Hun LEE ; Woo Won SHIN ; Hyun Sook AHN ; Jeong Hwan CHO ; Myung Sik SEONG ; Ki Tae KANG ; Byung Hee KIM ; Dong Yup JUNG ; Myung Hwan ROH ; Sang Young HAN ; Seok Reyol CHOI
Korean Journal of Medicine 2001;61(4):374-383
BACKGROUND: The emergence of YIDD or YVDD mutant hepatitis B virus (HBV), with point mutation in the YMDD motif of DNA polymerase gene, has been reported in patients with lamivudine treatment group. The aims of this study was to investigate the emergence of mutant HBV during long-term lamivudine therapy using nested polymerase chain reaction (PCR) method and direct DNA sequencing. METHODS: Twenty-one chronic hepatitis B patients with HBeAg and HBV DNA positive were evaluated. During lamivudine therapy, there were reported breakthroughs of HBV DNA (over 50 pg/mL) when investigated the emergence of YMDD mutants by nested PCR method using restriction fragment length polymorphism (RFLP) in all patients. Direct DNA sequencing of HBV DNA polymerase gene including YMDD motif was also performed. RESULTS: There were 13 patients (61.9%) with YIDD mutant and 8 patients (38.1%) with YVDD mutant. The results of direct DNA sequencing were consistent with those of nested PCR data based on RFLP. The breakthrough was occurred at 15 to 106 weeks (57.9+/-23.6). At the point of breakthrough, the level of ALT was 74.8+/-117.7 (14-546) IU/L, and it was lower than the level of ALT before the therapy. CONCLUSION: In the long-term therapy of lamivudine, the emergence of YMDD motif mutant HBV was related to the breakthrough of HBV DNA and YIDD mutant was frequent. The nested PCR method using RFLP may be simple and sensitive to detect the YMDD motif mutant HBV.
DNA
;
Hepatitis B e Antigens
;
Hepatitis B virus*
;
Hepatitis B*
;
Hepatitis B, Chronic
;
Hepatitis*
;
Humans
;
Lamivudine*
;
Point Mutation
;
Polymerase Chain Reaction
;
Polymorphism, Restriction Fragment Length
;
Sequence Analysis, DNA
4.Clinical characteristics of patients with chronic hepatitis B who developed genotypic resistance to entecavir: Real-life experience.
Hong Joo KIM ; Yong Kyun CHO ; Woo Kyu JEON ; Byung Ik KIM
Clinical and Molecular Hepatology 2017;23(4):323-330
BACKGROUND/AIMS: Clinical characteristics of patients with chronic hepatitis B (CHB) who developed genotypic resistance to entecavir (ETV) were compared to those without resistance. METHODS: Two hundred fifty eight CHB patients who underwent ETV treatment in our institution from July 2007 to May 2013 were included. RESULTS: Eight (3.1%) patients developed genotypic resistance to ETV during the follow-up period. The patterns of genotypic resistance to ETV were as follows: L180M + M204V + S202G (n=3); M204I + V173M (n=1); I169V + V173M (n=1); L180M + M204V + V173L (n=1); L180M + M204V + V173L + M250V (n=1); M204I + V214A + P237H (n=1). The cumulative occurrence rates of genotypic resistance to ETV were not significantly different between CHB patients with prior nucleos(t)tide analogues (NA) exposure (NA experienced, n=56) and NA naïve patients (n=202, P=0.823 by log rank comparison). Older age, higher baseline log10hepatitis B virus-deoxynucleic acid (log10HBV-DNA), higher log10HBV-DNA at 3, 6, 12 and 24 months after baseline, and complete virologic response (CVR, undetectable serum HBV-DNA by polymerase chain reaction 6 months after ETV treatment) were significant contributors to the development of genotypic resistance to ETV. Multivariate analyses showed higher log10HBV-DNA 6 months after baseline and absence of CVR were independent and significant contributors to the development of ETV resistance. CONCLUSIONS: Clinical characteristics of patients who developed ETV resistance were higher log10HBV-DNA 6 months after baseline and absence of CVR during the ETV treatment.
Follow-Up Studies
;
Hepatitis B e Antigens
;
Hepatitis B, Chronic*
;
Hepatitis, Chronic*
;
Humans
;
Multivariate Analysis
;
Polymerase Chain Reaction
5.An in vitro model of hepatitis B virus gene replication and expression in primary rat hepatocytes transfected with circular viral DNA.
Yun Qing YAO ; Ding Feng ZHANG ; Yun LUO ; Da Zhi ZHANG ; Al Long HUANG ; Bo WANG ; Wei Ping ZHOU ; Hong REN ; Shu Hua GUO
Chinese Journal of Hepatology 2002;10(4):275-278
<b>OBJECTIVEb>To establish an in vitro model of hepatitis B virus (HBV) replication and expression in primary rat hepatocytes (PRH) transfected with circular viral DNA for further study on the interaction of HBV with hepatocytes.
<b>METHODSb>Circular viral DNA containing complete HBV genome were transfected into PRH by electroporation (transfected group, about 4mug of circular viral DNA/1 10(7)cells). From day 1 to day 10 after transfection, HBsAg and HBeAg in the supernatants and lysates of PRH were measured with IMX system. HBcAg was assayed with western blotting, immunol dot blotting and immunocytochemistry. Meanwhile, HBV S-mRNA and X-mRNA were tested with RT-PCR, and replicative intermediates of HBV DNA were analyzed by southern blotting and dot blotting. Moreover, Transmission electron microscopy was used if viral particles were produced in transfected rat hepatocytes. PRH electroporated only was used as control group.
<b>RESULTSb>(1) Viral antigen production in transfected rat hepatocytes: HBsAg in cell lysates was positive. P/N values ranged from 4.83 to 85.69, and could be maintained for 10 days after transfection. The average P/N values was 18.239 27.459. Whereas, HBsAg was negative in the supernatants of transfected group (P/N values, negative<2.1). HBeAg in the supernatants and lysates of transfected hepatocytes all was negative (P/N values<2.1) during 10 days following transfection. HBcAg was only found positive in transfected hepatocytes by immunol dot blotting. (2) Detection of viral transcripts: transcription of HBV DNA was investigated by preparing total RNA from rat hepatocytes 2 days after transfection and looking for S-mRNA and X-mRNA by RT-PCR. Results showed S-mRNA positive, X-mRNA negative. (3) HBV DNA replication analysis: intracellular total DNA was extracted 2 days after transfection and analysed by southern blotting. All replicative DNA intermediates, including relaxed circular (rcDNA), covalently closed circular (cccDNA), and single-stranded (ssDNA) linear HBV DNA forms, were indicated. Dot blotting showed intracellular HBV DNA positive in transfected group during 10 days after transfection. However, viral particles were not found in transfected hepatocytes during 3 days after transfection.
<b>CONCLUSIONSb>Circular HBV DNA transfected into primary adult rat hepatocytes could obtain continuous replication and stable expression of HBV surface antigen. This in vitro model has high reproducibility and stability, and is useful for directly studying the interaction of HBV with hepatocytes.
Animals ; DNA Replication ; DNA, Circular ; genetics ; DNA, Viral ; genetics ; Gene Expression ; Hepatitis B Core Antigens ; analysis ; Hepatitis B Surface Antigens ; analysis ; Hepatitis B e Antigens ; analysis ; Hepatitis B virus ; genetics ; Hepatocytes ; virology ; Male ; Rats ; Rats, Wistar ; Transfection ; Virus Replication
6.Analysis of the test results of HBV serum markers and HBV DNA of the neonates born to HBsAg-positive mothers.
Miao-Chan WANG ; Ai-Fang XU ; Yong-Le ZHANG ; Dong-Ming XU
Chinese Journal of Experimental and Clinical Virology 2011;25(6):445-447
<b>OBJECTIVEb>To observe the HBV serum markers and HBV DNA expressions of the neonates born to the HBsAg-positive mothers.
<b>METHODSb>By detecting serum immunity markers of hepatitis B virus (5 items) and serum HBV DNA of 283 neonates (a pair of twins) born to 282 HBsAg-positive mothers.
<b>RESULTSb>12 patterns emerge from the study of the hepatitis B serum markers of 283 neonates. Topping the list is the combination of HBeAg and anti-HBc positive accounting for 48.41% (137/283), followed by the combination of anti-HBe and anti-HBc positive accounting for 22.26% (62/283). The third highest combination is that of HBsAg, HBeAg and anti-HBc positive accounting for 12.37% (35/283). There are five combinations accounting for 16.61% (47/283), each with HBsAg-positive. No case is found of the five items all negative or only HBsAb positive. Five cases are detected of serum HBV DNA > or = 1 x 103 IU/ml accounting for 1.77%.
<b>CONCLUSIONSb>Neonates born to HBsAg-positive mothers display complex patterns of serum hepatitis B markers, the dominant pattern being the combination of HBeAg and anti-HBc positive. Cases of serum HBV DNA > or = 1 x 10(3) IU/ml are rare.
Biomarkers ; blood ; DNA, Viral ; analysis ; Female ; Hepatitis B ; transmission ; Hepatitis B Antibodies ; blood ; Hepatitis B Core Antigens ; blood ; Hepatitis B Surface Antigens ; blood ; Hepatitis B e Antigens ; blood ; Humans ; Infant, Newborn ; Infectious Disease Transmission, Vertical ; Male
7.Association of Cytokines with Alanine Aminotransferase, Hepatitis B Virus Surface Antigen and Hepatitis B Envelope Antigen Levels in Chronic Hepatitis B.
Ming-Hui LI ; Yao LU ; Lu ZHANG ; Xing-Yue WANG ; Chong-Ping RAN ; Hong-Xiao HAO ; Dan ZHANG ; Xiao-Jing QU ; Ge SHEN ; Shu-Ling WU ; Wei-Hua CAO ; Tian-Lin QI ; Ru-Yu LIU ; Lei-Ping HU ; Min CHANG ; Wen-Hao HUA ; Shun-Ai LIU ; Gang WAN ; Yao XIE
Chinese Medical Journal 2018;131(15):1813-1818
Background:
Cytokines play an important role in occurrence and recovery of hepatitis B virus (HBV) infection. The aim of this study was to investigate the changes of cytokines concentration and its correlation to alanine aminotransferase (ALT), HBV deoxyribonucleic acid (HBV-DNA), hepatitis B envelope antigen (HBeAg), and HBV surface antigen (HBsAg) in the development of chronic hepatitis B (CHB).
Methods:
Thirteen healthy individuals (HI), 30 chronic HBV-infected patients in immune tolerant (IT) phase, and 55 CHB patients were enrolled between August 2015 and May 2017. The peripheral blood samples were collected from all individuals. The levels of interferon (IFN)-α2, interleukin (IL)-10, transforming growth factor (TGF)-β1, HBV-DNA, HBsAg, and HBeAg and liver function were measured. The quantitative determinations of cytokines levels, including IFN-α2, IL-10, and TGF-β1 were performed using Luminex multiplex technology. The correlation of cytokines to ALT, HBV-DNA, HBsAg, and HBeAg was analyzed by linear regression analysis.
Results:
IFN-α2 levels were similar between HI and IT groups (15.35 [5.70, 67.65] pg/ml vs. 15.24 [4.07, 30.73] pg/ml, Z = -0.610, P = 0.542), while it elevated significantly in CHB group (35.29 [15.94, 70.15] pg/ml vs. 15.24 [4.07, 30.73] pg/ml; Z = -2.522, P = 0.012). Compared with HI group (3.73 [2.98, 11.92] pg/ml), IL-10 concentrations in IT group (5.02 [2.98, 10.11] pg/ml), and CHB group (7.48 [3.10, 18.00] pg/ml) slightly increased (χ = 2.015, P = 0.365), and there was no significant difference between IT and CHB group (Z = -1.419, P = 0.156). The TGF-β1 levels among HI (3.59 ± 0.20 pg/ml), IT (3.62 ± 0.55 pg/ml), and CHB groups (3.64 ± 0.30 pg/ml) were similar (χ = 2.739, P = 0.254). In all chronic HBV-infected patients (including patients in IT and CHB groups), the elevation of IFN-α2 level was significantly associated with ALT level (β= 0.389, t = 2.423, P = 0.018), and was also negatively correlated to HBV-DNA load (β = -0.358, t = -2.308, P = 0.024), HBsAg (β = -0.359, t = -2.288, P = 0.025), and HBeAg contents (β = -0.355, t = -2.258, P = 0.027). However, when both ALT level and cytokines were included as independent variable, HBV-DNA load, HBsAg, and HBeAg contents were only correlated to ALT level (β = -0.459, t = -4.225, P = 0.000; β = -0.616, t = -6.334, P = 0.000; and β = -0.290, t = -2.433, P = 0.018; respectively).
Conclusions
IFN-α2 elevation was associated with ALT level in patients with chronic HBV infection. However, in CHB patients, only ALT level was correlated to HBV-DNA, HBsAg and HBeAg contents.
Adult
;
Alanine Transaminase
;
blood
;
Antigens, Surface
;
Case-Control Studies
;
Cytokines
;
blood
;
DNA, Viral
;
Female
;
Hepatitis B
;
Hepatitis B Surface Antigens
;
analysis
;
Hepatitis B e Antigens
;
Hepatitis B virus
;
Hepatitis B, Chronic
;
blood
;
immunology
;
Humans
;
Male
;
Young Adult
8.Alteration of the glycan profile of serum glycoproteins during the seroconversion process in hepatitis B virus-infected patients treated with antiviral therapy and its clinical significance.
Youlan GU ; Yuwen TANG ; Xiaodong ZHOU ; Yinkun LIU
Chinese Journal of Hepatology 2014;22(9):660-666
<b>OBJECTIVEb>To use a lectin microarray to study the alteration of glycan affinity profiles of serum glycoproteins during the hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) seroconversion in patients with chronic hepatitis B (CHB) following treatment with antiviral therapy,and to explore its biological significance.
<b>METHODSb>CHB patients were divided into the following four groups:untreated HBeAg-positive,HBeAg seroconversion after anti-HBV therapy,HBsAg loss after anti-HBV therapy,and healthy individuals (controls).Serum samples were collected from each participant,depleted of high abundance proteins and analyzed by a lectin microarray containing 50 lectins.The lectin-affinity glycan profiles of serum proteins were partially verified by lectin blotting.Between-group differences were analyzed by one-way analysis of variance,and pairwise comparisons were carried out with the Student-Newman-Keuls (SNK) method.
<b>RESULTSb>The results from the lectin microarray and lectin blotting assay showed significantly reduced affinity for 16 lectins in the untreated HBeAg-positive group compared to the control group (P less than 0.05);in addition,the specific glycan profiles of the untreated HBeAg-positive group included decreased terminal and core fructose,GalNAc alpha-Thr/Ser (T,Tn-antigen),GalNac alpha,terminal beta1-4,and beta-D galactose,bisecting and/or GlcNAc,mannose and Sia.However,the HBeAg seroconversion after anti-HBV therapy group showed enhanced binding of PSA,MPL and the above-mentioned 16 lectins (P less than 0.05),suggesting that the reduced serum glycoprotein glycan structures returned to normal or slightly higher than healthy levels after the therapy-induced seroconversion.Comparison of the group with HBsAg loss after anti-HBV therapy to the group with HBeAg seroconversion after anti-HBV therapy showed the binding ability of ten lectins (AAL,ACL,HAL,HPL,RCA-I,LEL,STL,PHA-E,NML and PCL) were weakened to near control levels and six lectins (VAL,LCA,GNL,PSA,MPL and JAC) were significantly strengthened (all P less than 0.05). These findings implied that the glycan containing terminal fructose, GalNacalpha, terminal beta1-4 galactose,and bisecting GlcNAc glycan structures dropped to near control levels, while the terminal beta-D-galactose residues and core fructose structure increased significantly.
<b>CONCLUSIONb>The glycan structures of serum glycoproteins are closely related to HBeAg and HBsAg seroconversion in CHB patients.It is possible that a special lectin binding glycan involving the terminal beta-D-galactose residues and core fructose may act as sugar markers associated with the disappearance of serum HBsAg during anti-HBV therapy for CHB.
Antiviral Agents ; therapeutic use ; Galactose ; Glycoproteins ; blood ; Hepatitis B e Antigens ; Hepatitis B, Chronic ; drug therapy ; Humans ; Phytohemagglutinins ; Polysaccharides ; analysis
9.Current Role of Lamivudine Regarding Therapeutic Response and Resistance in Children with Chronic Hepatitis B.
Suk Jin HONG ; Yeo Hyang KIM ; Byung Ho CHOE ; Hyo Jung PARK ; Won Young TAK ; Young Oh KWEON
Pediatric Gastroenterology, Hepatology & Nutrition 2013;16(2):80-88
PURPOSE: To identify the predictive factors of long-term therapeutic response or resistance to lamivudine treatment in children and adolescents with chronic hepatitis B. METHODS: Eighty one children and adolescents with chronic hepatitis B were included, who received lamivudine treatment for at least 6 months. Their condition was monitored for at least 12 months (12-88 months) thereafter. Twenty one (25.9%) were preschool children (age< or =6). For patients who had developed HBeAg seroconversion or breakthrough, univariate and multivariate analyses were used to identify the effects of age, gender, pretreatment alanine aminotransferase (ALT) and hepatitis B virus DNA levels. RESULTS: HBeAg seroconversion occurred in 49 (60.5%) of the 81 patients after the initiation of the lamivudine therapy. In 65 patients whom were monitored for over 24 months, the seroconversion rate was significantly higher in younger patients (p=0.040), especially in those patients of preschool age (age< or =6, p=0.031). The seroconversion rate was significantly higher in higher pretreatment ALT (p=0.003). The breakthrough occurred in 21 (25.9%) of the 81. The breakthrough rate was lower in younger aged patients (age< or =6), and with higher pretreatment ALT levels, but no significant difference. CONCLUSION: Younger age is a good predictor of HBeAg seroconversion in children with long-term lamivudine treatment as well as high pretreatment ALT levels.
Adolescent
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Aged
;
Alanine Transaminase
;
Child
;
Child, Preschool
;
DNA
;
Hepatitis B e Antigens
;
Hepatitis B virus
;
Hepatitis B, Chronic
;
Hepatitis, Chronic
;
Humans
;
Lamivudine
;
Multivariate Analysis
10.Clinical Efficacy of Entecavir and Factors Predicting Long-Term Treatment Response in Nucleoside-Naive Patients with Chronic Hepatitis B.
Beom Hee KIM ; Beom Yong YOON ; Dae Wha PARK ; Eaum Seok LEE ; Seok Hyun KIM ; Byung Seok LEE ; Heon Young LEE
Korean Journal of Medicine 2013;85(2):157-166
BACKGROUND/AIMS: The aims of this study were to characterize the treatment response to entecavir and to examine factors affecting that response. METHODS: A total of 77 nucleoside-naive patients with chronic hepatitis B who had received entecavir (0.5 mg daily) for at least 48 weeks were consecutively enrolled between March 2007 and March 2011. The rates of virological response (hepatitis B virus [HBV] DNA < 116 copies/mL), biochemical response (alanine aminotransferase < or = upper limit of normal), hepatitis B e antigen (HBeAg) loss, and seroconversion were retrospectively analyzed. RESULTS: The cumulative rates of virological response at 12, 24, 48, 96, and 144 weeks were 59.7%, 82%, 88.3%, 89.6%, and 93.1%, respectively; biochemical response rates were 51.9%, 74%, 84.4%, 94.8%, and 98.3%, respectively; HBeAg loss rates were 10.5%, 18.4%, 28.9%, 36.8%, and 47.4%, respectively; and HBeAg seroconversion rates were 7.9%, 18.4%, 21.1%, 28.9%, and 39.5%, respectively. In multivariate analysis, independent predictors associated with HBV DNA polymerase chain reaction (PCR) negativity were the absence of HBeAg at baseline (p = 0.006) and early virological response (HBV DNA < 2,000 copies/mL after 12 weeks of therapy; p = 0.027). In univariate analysis, early virological response was an independent factor predicting HBeAg loss (p = 0.001). CONCLUSIONS: Entecavir induced excellent biochemical and virological responses in nucleoside-naive patients with chronic hepatitis B. Early virological response was an independent factor predicting HBV PCR negativity and HBeAg loss, and can be used to predict long-term treatment response to entecavir.
Decision Support Techniques
;
DNA
;
Guanine
;
Hepatitis B
;
Hepatitis B e Antigens
;
Hepatitis B, Chronic
;
Hepatitis, Chronic
;
Herpesvirus 1, Cercopithecine
;
Humans
;
Multivariate Analysis
;
Polymerase Chain Reaction
;
Retrospective Studies