Detection of Occult Hepatitis B Virus Among Iranian HCV-Infected Patients with Hemophilia Treated with Direct-Acting Antiviral Agents


avatar Niloofar Naderi 1 , avatar Ghazal Masoudi 2 , avatar Bita Behnava 3 , avatar Seyed Moayed Alavian ORCID 3 , avatar Soyar Sari 2 , avatar Ali Anvar 1 , avatar Alireza Azizi Saraji 1 , avatar Ali Namvar 1 , * , avatar Azam Bolhassani 4 , **

Iranian Comprehensive Hemophilia Care Center, Tehran, Iran
Department of Molecular and Cellular Sciences, Faculty of Advanced Sciences and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
Baqiyatallah Research Center for Gastroenterology and Liver Diseases, Baqiyatallah University of Medical Sciences, Tehran, Iran
Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran
Corresponding Authors:

how to cite: Naderi N, Masoudi G, Behnava B, Alavian S M, Sari S, et al. Detection of Occult Hepatitis B Virus Among Iranian HCV-Infected Patients with Hemophilia Treated with Direct-Acting Antiviral Agents. Hepat Mon.18(12):e83337. doi: 10.5812/hepatmon.83337.



One of the challenges to treat hepatitis C virus (HCV) infection is the activation of hepatitis B virus (HBV) that occurs during treatment of HCV infection with direct-acting antivirals (DAAs) in some patients. The detection of serum or liver HBV DNA in the absence of serum HBsAg (HBV surface antigen) is described as occult HBV infection (OBI).


The current study aimed at determining the prevalence of OBI in Iranian DAA-naïve HCV-infected patients with hemophilia.


The current study was conducted on 100 patients with hemophilia receiving DAAs. The sera obtained from these patients were tested for the presence of HBsAg. Then, the presence of the HBV DNA was detected in peripheral blood mononuclear cell (PBMC) and also plasma samples using nested polymerase chain reaction (PCR).


Among the 100 study subjects, 81 (81%) were male and 19 (19%) female. The mean age of the patients was 37 ± 10.50 years. All patients had previously received HBV vaccine. In the current study, HBV DNA was observed in 1% of plasma and in 3% of PBMC samples. In addition, none of the patients who had positive result for HBV detection test previously had markers of HBV infection (anti-HBc (HB core antigen) antibodies, anti-HBs antigens, and positive result of DNA PCR) and all had negative results for HCV RNA after treatment.


Generally, the prevalence of OBI was low, but however, HBsAg negativity was not sufficient to completely exclude the presence of HBV DNA. Thus, the serological markers of HBV infection should be confirmed by molecular tests for the presence of possible occult infection.

1. Background

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the most common causes of chronic liver diseases in the world (1). More than 75% of individuals exposed to HCV develop chronic infection (2). In addition, more than 71 million individuals are infected with HCV in the world (3, 4). On the other hand, more than 248 million individuals with chronic HBV infection were identified by their HBV surface antigen (HBsAg) seroprevalence worldwide (5). The presence of liver or serum HBV DNA in the absence of serum HBsAg is defined as occult HBV infection (OBI) (6, 7). In addition, nearly 20% of cases with OBI do not have markers of pervious HBV infection. Various reasons are suggested to explain this situation, such as a mutation in the S gene and suppressor role of HCV on HBsAg. HBV activation could be associated with severe hepatitis and liver failure (6-13). There are conflicting data whether HBV replication may be inhibited by coinfection with other agents, especially HCV or HIV (14-20). Although HBV replication is commonly inhibited in the presence of HCV coinfection, a total HBV activation rate of 14.5% is reported following interferon (IFN)-induced HCV eradication (21) .Thus, the individuals with active HBV and HCV infections likely show a high HCV viral load, and low or undetectable HBV DNA levels. After HCV suppression, their HBV could become reactivate, or more aggressive with high HBV DNA levels and low HCV RNA detection (22). HBV reactivation was reported in patients with HCV infection treated with direct-acting antivirals (DAAs) (9, 23). The early direct-acting antiviral agents known as IFN-free treatment were approved by the Food and Drug Administration (FDA) as the treatment of chronic HCV infection in 2013, which greatly eradicated HCV from infected livers (9, 24). Also, DAAs were related to HBV activation both in HBsAg-positive patients, and HBsAg-negative subjects with OBI (6, 25). Currently, there are four classes of DAAs: NS3/NS4A serine protease inhibitors, NS5A inhibitors, NS5B polymerase inhibitors, and cyclophilin inhibitors (26).The major goal of antiviral therapy is to eradicate HCV from the serum and achieve a sustained virological response (SVR), defined as the lack of HCV in the serum 12 - 24 weeks after completion of therapy (26, 27). Recently, some studies assessed the risk of HBV reactivation in patients infected with HCV receiving interferon (IFN)-free DAAs. However, the incidence and the clinical aspects of HBV reactivation after IFN-free DAAs for HCV are not completely determined (28).

2. Objectives

The current study aimed at analyzing the total risk of occult HBV in Iranian DAA-naïve HCV-infected patients with hemophilia.

3. Methods

3.1. Study Population

From April 2015 to September 2017, one hundred patients with hemophilia receiving IFN-free DAA regimen to treat HCV infection were enrolled in the Comprehensive Hemophilia Care Center in Iran. Before treatment onset, plasma HCV RNA level, and HCV genotype and subtype were collected from patients’ medical records. Patients were followed up during treatment and every four weeks after completion of the treatment for 12 weeks, and their clinical parameters and serum HCV RNA levels were assessed by Cobas Taqman HCV (Roche Molecular Systems). In the current descriptive, cross sectional study, demographic and medical characteristics of patients (age, gender, history of blood transfusion, intravenous drug abuse, history of surgical procedures, medical history (HBV infection or other diseases), family history of hepatitis, and history of hepatitis B vaccination) and laboratory tests data (e.g., aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, HbsAg, triglyceride, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and fasting blood glucose (FBS) were collected (Table 1) and transferred into a checklist. The protocol of the study was approved by Ethics Committee of the Iranian Comprehensive Hemophilia Care Center. All participants signed written informed consent, and the study objectives were explained to all of them.

Table 1. Demographic Characteristics and Laboratory Tests Data of the Study Participantsa
VariablePatients with Hemophilia, N = 100
Age, y37 ± 10.50
Male81 (81)
Female19 (19)
Total bil, mg/dL1.53 ± 1.08
Direct bil, mg/dL0.32 ± 0.17
AST, U/L30.94 ± 19.91
ALT, U/L28.77 ± 22.45
PT, sec12.82 ± 8.98
INR1.24 ± 0.72
Hb, mg/dL14.07 ± 2.88
WBCs, × 103/µL7.1 ± 3.26
RBCs, × 106/µL4.78 ± 0.84
FBS, mg/dL99.83 ± 23.32
Urea, mg/dL31.55 ± 9.59
Creatinine, mg/dL0.99 ± 0.29
Uric acid, mg/dL5.78 ± 1.93
Cholesterol, mg/dL152.70 ± 44.26
TG, mg/dL110.38 ± 43.01
LDL Chol, mg/dL75.18 ± 25.99
HDL Chol, mg/dL40.50 ± 11.12
HBcAbNegative (93%), Positive (7%)
HBsAb, mIU73.21 ± 45.21

3.2. Serological Tests Using ELISA

A 5 - 6-mL blood sample obtained from each patient was drained in a sterile tube containing ethylene diamine tetra-acetic acid (EDTA) 12 weeks after DAAs therapy. Sera were separated by centrifugation and tested for the presence of HBsAg, HBcAb, and HBsAb using the enzyme-linked immunoassay (ELISA) commercial kits (Dia. Pro, Italy) according to the manufacturer’s protocol.

3.3. Preparation of PBMCs and Plasma

At first, a 5 - 6-mL peripheral blood sample obtained from each patient was drained into a sterile EDTA-containing Vacutainer tube. After separation of plasma by centrifugation, the peripheral blood mononuclear cells (PBMCs) of the samples were separated using the standard method of Ficoll density gradient centrifugation (LympholyteHTM; Cedarlane and Hornby; Canada). The PBMC pellets were washed with phosphate buffered saline (PBS; pH 7.4), and stored at -80°C for HBVDNA extraction. The studies showed that the long term storage of human PBMCs can be performed by cryopreservation with 10% dimethylsulfoxide (DMSO) as freezing medium containing intracellular cryoprotectant plus 90% heat inactivated fetal calf serum (29, 30).

3.4. Molecular Assays Using Nested PCR

All DNAs of PBMC and plasma samples were extracted using NucleoSpin® blood kit (Machery-Nagel, Germany) and NucleoSpin® Dx virus kit (Machery-Nagel, Germany) according to the manufacturer’s protocol, respectively. DNAs were eluted and stored at -20°C for HBV DNA detection. The primers were designed by NCBI-Primer BLAST database. Then, SnapGene software was employed to investigate the validity of sequences (Table 2). To confirm OBI, the nested polymerase chain reaction (PCR) was performed in a 30-µL reaction volume containing 5 µL of DNA sample for the first and 1 µL for the second round of PCR, 10 pmol of each primer, and PCR-Master mix (amplicon, Korea). In the first and the second round of PCR, DNA was amplified for five cycles at 94°C for one minute, 55°C for one minute, and 72°C for 90 seconds, followed by 35 cycles of denaturation at 90°C. For positive and negative controls, the plasma and PBMC samples of 10 patients with HBV infection and 10 healthy blood donors were used, respectively. In addition, pretreatment plasma samples were checked for the presence of HBV DNA in HBV-positive samples.

Table 2. Oligonucleotide Primers to Detect Occult HBV DNA Through Nested PCR Amplification
GenePrimer SequencePosition on Chr, bpPolarity
HBV genomic regions (surface region)Forward inner primer5’-AGGTATGTTGCCCGTTTGTCCT-3’383S
Reverse inner primer5’-GGGTTTAAATGTATACCCA-3’A
Forward outer primer5’-CCTGCTGGTGGCTCCAGTTC-3’948S

3.5. Data Analysis

The data obtained from demographic information of patients were expressed as the mean ± standard deviation (SD) with SPSS or Excel software. The frequency or percentage was used for descriptive analysis.

4. Results

4.1. Study Population

The blood samples of 100 Iranian patients with hemophilia were collected 12 weeks after receiving DAA therapy. The patients with HCV infection were treated with DAA regimen including daclatasvir/sofosbuvir and ledipasvir/sofosbuvir. The DAA regimens including daclatasvir/sofosbuvir fixed dose (n = 18.18%) and ledipasvir/sofosbuvir fixed dose (n = 82.82%) were administered to patients (with or without ribavirin). All of patients were HBsAg-seronegative and HBcAb test result was positive in seven (7%) patients. The mean serum level of HBsAb was 73.21 ± 45.21. None of them were infected with HIV. Table 1 shows the demographic characteristics and laboratory tests data of the study participants. The mean age of the patients was 37 ± 10.50 years, ranged 23 to 64, of which 81 (81%) were male and 19 (19%) female.

4.2. Detection of OBI in the Study Participants

Of the 100 patients achieving SVR (undetectable HCV RNA 12 weeks after treatment), HBV DNA was found in one (1%) plasma and three (3%) PBMC samples. All these patients were male (n = 3, mean age = 32 years).One patient had a positive PCR test both for plasma and PBMC samples. All of the HBV-positive patients were seronegative for HBcAb and HbsAg markers. DAA regimens of HBV-positive samples were ledipasvir/sofosbuvir and pretreatment HBV PCR results were negative. In addition, the activities of serum ALT and AST were collected from patients’ medical records. For all patients, mean serum levels of ALT and AST were 28.77 ± 22.45 and 30.94 ± 19.91 mg/mL, respectively. The current study findings showed that AST activity was within the normal range for both PBMC and plasma positive samples. In two patients, ALT levels were normal, but its level remarkably increased in the PBMC-positive sample (53 U/L) compared with the normal range (Table 3).

Table 3. Characteristics of Patients with Occult HBV Infection
Variables Patient ID
Age, y323135
ALT level, mg/dL
Post treatment531811
AST level, mg/dL
Post treatment322429
Post treatmentPositive (PBMC)Positive (PBMC and plasma)Positive (PBMC)
Post treatmentNegativeNegativeNegative
Baseline< 100> 100> 100
Post treatment< 4> 100> 100

5. Discussion

The current study aimed at determining the prevalence of OBI in DAA-naïve HCV-infected patients with hemophilia. Different concerns caused HBV activation after successful clearance of HCV through the use of DAA therapy in patients with HCV infection (31). HCV treatment and the alteration of immune synergy in coinfection could be considered as a reason for the risk of HBV activation (13). The current study demonstrated that in 100 HBsAg-negative patients, HBV DNA was detected in 1% of the plasma and 3% of PBMC samples. Indeed, 3% of patients were at the risk of HBV activation after DAA therapy. The examinations were performed on Iranian DAA-naïve HCV-infected patients with hemophilia evaluated for OBI through the analysis of both plasma samples and PBMCs. Results of the current study demonstrated no additional risk of OBI after cessation of DAA therapy for HCV infection. To date, OBI is reported in patients with HIV, chronic HCV infection, hepatocellular carcinoma (HCC), advanced cryptogenic liver fibrosis, intravenous drug users, and the patients requiring permanent blood transfusion and hemodialysis (32).

A previous study showed that the prevalence of OBI was 0.5% among about 200 patients undergoing hemodialysis in Tehran, Iran. This result was confirmed by positive results of PCR testing for both the serum and PBMCs (32). In some studies, the prevalence of HCV/HBV coinfection was reported 15.6% to 48.9% (33). So far no other publication showed the frequency of OBI in HCV-infected patients treated with DAAs without any history of HBV infections. However, several studies pointed out that HBV reactivation related to DAA treatment occurred in 2.1% - 57.1% of the HBsAg-positive patients and frequently during DAA treatment (30). In general, both HCV and HBV have developed mechanisms to escape the host immune responses to develop chronic infection (33). Some studies represented that HBV infection can be inhibited by HCV infection with a suppressing effect of HCV core proteins on HBV replication (34). Indeed, actively replicated HCV could induce a host immune system suitable to control HBV replication. Therefore, treatment of HCV infection with drugs could change immune response against HBV replication resulting in HBV activation (9, 35). For instance, Londono et al., showed that HBV reactivation occurred as an increase in HBV DNA levels ≥ 1 log in patients with chronic hepatitis C (CHC) receiving an IFN-free regimen (36). Wang et al., demonstrated that HBV reactivation had a prevalence of about 3.1% in 327 HBsAg-positive patients receiving DAAs oral regimen for HCV infections (37). Similarly, Calvaruso et al., reported eight HBsAg-positive cases (7.7%) in 104 patients treated with DAAs (38). In China, Huang et al., showed that 50% of HBsAg-positive and 1.6% of anti-HBc-positive patients presented HBV reactivation during treatment with DAAs without any clinical features (34). A cohort study by Tyson et al., indicated that HBV transmission was predominant in the United States adults, since the prevalence of HBV coinfection in HCV-positive American veterans was low (39). Some reports from Egypt and Turkey represented that the prevalence of HBV coinfection in patients with HCV infection was 0.7% and 2.6%, respectively (40, 41). In contrast to other studies, Ozaras et al. indicated that treatment with DAAs led to hepatitis caused by HBV reactivation in OBI-positive patients with CHC (42). Similarly, Kawagishi et al., showed that five (5.7%) of 87 patients with previous HBV infection presented HBV-reactivation and/ or detectable HBV-DNA during IFN-free DAA treatment (43).

5.1. Conclusions

In conclusion, results of the current study showed that the overall prevalence of OBI was 3% among 100 patients with hemophilia receiving DAAs, confirmed by positive results of nested PCR testing for both the plasma samples and PBMCs. As observed in the current study, the prevalence of OBI in such patients was likely low due to regular vaccination for HBV or other unknown agents. However, further studies with more exact laboratory techniques and larger sample sizes are required to improve OBI screening, especially in blood transfusion centers.


  • 1.

    Pawlowska M, Domagalski K. Risk of HBV reactivation in patients infected with HBV/HCV treated with DAA. Hepat Mon. 2017;17(8). e12317. doi: 10.5812/hepatmon.12317.

  • 2.

    Mandour M, Nemr N, Shehata A, Kishk R, Badran D, Hawass N. Occult HBV infection status among chronic hepatitis C and hemodialysis patients in Northeastern Egypt: Regional and national overview. Rev Soc Bras Med Trop. 2015;48(3):258-64. doi: 10.1590/0037-8682-0037-2015. [PubMed: 26108002].

  • 3.

    Messina JP, Humphreys I, Flaxman A, Brown A, Cooke GS, Pybus OG, et al. Global distribution and prevalence of hepatitis C virus genotypes. Hepatology. 2015;61(1):77-87. doi: 10.1002/hep.27259. [PubMed: 25069599]. [PubMed Central: PMC4303918].

  • 4.

    Averhoff FM, Glass N, Holtzman D. Global burden of hepatitis C: Considerations for healthcare providers in the United States. Clin Infect Dis. 2012;55 Suppl 1:S10-5. doi: 10.1093/cid/cis361. [PubMed: 22715208].

  • 5.

    Schweitzer A, Horn J, Mikolajczyk RT, Krause G, Ott JJ. Estimations of worldwide prevalence of chronic hepatitis B virus infection: A systematic review of data published between 1965 and 2013. Lancet. 2015;386(10003):1546-55. doi: 10.1016/S0140-6736(15)61412-X. [PubMed: 26231459].

  • 6.

    Wu T, Kwok RM, Tran TT. Isolated anti-HBc: The relevance of hepatitis B core antibody: A review of new issues. Am J Gastroenterol. 2017;112(12):1780-8. doi: 10.1038/ajg.2017.397. [PubMed: 29087395].

  • 7.

    Saffioti F, Raimondo G. What do we know about occult hepatitis B virus infection? APMB. 2017;105(2):1-13. doi: 10.6092/1828-6550/APMB.105.2.2017.SD2.

  • 8.

    Calvaruso V, Craxi A. HBV recurrence after HCV clearance on DAAs: Sometimes they come back. J Hepatol. 2017;67(5):898-901. doi: 10.1016/j.jhep.2017.08.017. [PubMed: 28864279].

  • 9.

    Wahle RC, Perez RM, Pereira PF, Oliveira EM, Emori CT, Uehara SN, et al. Hepatitis B virus reactivation after treatment for hepatitis C in hemodialysis patients with HBV/HCV coinfection. Braz J Infect Dis. 2015;19(5):533-7. doi: 10.1016/j.bjid.2015.04.003. [PubMed: 25997784].

  • 10.

    Konstantinou D, Deutsch M. The spectrum of HBV/HCV coinfection: Epidemiology, clinical characteristics, viralinteractions and management. Ann Gastroenterol. 2015;28(2):221-8. [PubMed: 25830779]. [PubMed Central: PMC4367211].

  • 11.

    Mucke MM, Backus LI, Mucke VT, Coppola N, Preda CM, Yeh ML, et al. Hepatitis B virus reactivation during direct-acting antiviral therapy for hepatitis C: A systematic review and meta-analysis. Lancet Gastroenterol Hepatol. 2018;3(3):172-80. doi: 10.1016/S2468-1253(18)30002-5. [PubMed: 29371017].

  • 12.

    Evens AM, Jovanovic BD, Su YC, Raisch DW, Ganger D, Belknap SM, et al. Rituximab-associated hepatitis B virus (HBV) reactivation in lymphoproliferative diseases: Meta-analysis and examination of FDA safety reports. Ann Oncol. 2011;22(5):1170-80. doi: 10.1093/annonc/mdq583. [PubMed: 21115603]. [PubMed Central: PMC3082161].

  • 13.

    Paul S, Saxena A, Terrin N, Viveiros K, Balk EM, Wong JB. Hepatitis B virus reactivation and prophylaxis during solid tumor chemotherapy: A systematic review and meta-analysis. Ann Intern Med. 2016;164(1):30-40. doi: 10.7326/M15-1121. [PubMed: 26595058].

  • 14.

    Boccaccio V, Bruno S. Optimal management of patients with chronic hepatitis C and comorbidities. Liver Int. 2015;35 Suppl 1:35-43. doi: 10.1111/liv.12712. [PubMed: 25529086].

  • 15.

    Raimondo G, Cacciamo G, Saitta C. Hepatitis B virus and hepatitis C virus co-infection: additive players in chronic liver disease? Ann Hepatol. 2005;4(2):100-6. [PubMed: 16010242].

  • 16.

    Bellecave P, Gouttenoire J, Gajer M, Brass V, Koutsoudakis G, Blum HE, et al. Hepatitis B and C virus coinfection: A novel model system reveals the absence of direct viral interference. Hepatology. 2009;50(1):46-55. doi: 10.1002/hep.22951. [PubMed: 19333911].

  • 17.

    Tramuto F, Maida CM, Colomba GM, Di Carlo P, Vitale F. Prevalence of occult hepatitis B virus infection in a cohort of HIV-positive patients resident in Sicily, Italy. Biomed Res Int. 2013;2013:859583. doi: 10.1155/2013/859583. [PubMed: 24063015]. [PubMed Central: PMC3770005].

  • 18.

    Oliveira MP, Lemes PS, Matos MA, Del-Rios NH, Carneiro MA, Silva AM, et al. Overt and occult hepatitis B virus infection among treatment-naive HIV-infected patients in Brazil. J Med Virol. 2016;88(7):1222-9. doi: 10.1002/jmv.24462. [PubMed: 27061406].

  • 19.

    Omar HH, Taha SA, Hassan WH, Omar HH. Impact of schistosomiasis on increase incidence of occult hepatitis B in chronic hepatitis C patients in Egypt. J Infect Public Health. 2017;10(6):761-5. doi: 10.1016/j.jiph.2016.11.010. [PubMed: 28196636].

  • 20.

    McClary H, Koch R, Chisari FV, Guidotti LG. Inhibition of hepatitis B virus replication during schistosoma mansoni infection in transgenic mice. J Exp Med. 2000;192(2):289-94. [PubMed: 10899915]. [PubMed Central: PMC2193253].

  • 21.

    Chen G, Wang C, Chen J, Ji D, Wang Y, Wu V, et al. Hepatitis B reactivation in hepatitis B and C coinfected patients treated with antiviral agents: A systematic review and meta-analysis. Hepatology. 2017;66(1):13-26. doi: 10.1002/hep.29109. [PubMed: 28195337].

  • 22.

    Gish RG. HBV/HCV coinfection and possible reactivation of HBV following DAA use. Gastroenterol Hepatol (N Y). 2017;13(5):292-5. [PubMed: 28656026]. [PubMed Central: PMC5479342].

  • 23.

    Bersoff-Matcha SJ, Cao K, Jason M, Ajao A, Jones SC, Meyer T, et al. Hepatitis B virus reactivation associated with direct-acting antiviral therapy for chronic hepatitis C virus: A review of cases reported to the U.S. Food and Drug Administration Adverse Event Reporting System. Ann Intern Med. 2017;166(11):792-8. doi: 10.7326/M17-0377. [PubMed: 28437794].

  • 24.

    Ma K, Shokoohi S, Reau N. Reactivation of occult HBV infection in patients cured of HCV with direct-acting antivirals. Curr Treat Option Infect Dis. 2017;9(4):380-8. doi: 10.1007/s40506-017-0134-8.

  • 25.

    Suda T, Shimakami T, Shirasaki T, Yamashita T, Mizukoshi E, Honda M, et al. Reactivation of hepatitis B virus from an isolated anti-HBc positive patient after eradication of hepatitis C virus with direct-acting antiviral agents. J Hepatol. 2017;67(5):1108-11. doi: 10.1016/j.jhep.2017.07.014. [PubMed: 28739112].

  • 26.

    Shah N, Pierce T, Kowdley KV. Review of direct-acting antiviral agents for the treatment of chronic hepatitis C. Expert Opin Investig Drugs. 2013;22(9):1107-21. doi: 10.1517/13543784.2013.806482. [PubMed: 23735127].

  • 27.

    Ghany MG, Strader DB, Thomas DL, Seeff LB; American Association for the Study of Liver Diseases. Diagnosis, management, and treatment of hepatitis C: An update. Hepatology. 2009;49(4):1335-74. doi: 10.1002/hep.22759. [PubMed: 19330875].

  • 28.

    Liu CH, Liu CJ, Su TH, Fang YJ, Yang HC, Chen PJ, et al. Hepatitis B virus reactivation in patients receiving interferon-free direct-acting antiviral agents for chronic hepatitis C virus infection. Open Forum Infect Dis. 2017;4(1):ofx028. doi: 10.1093/ofid/ofx028. [PubMed: 28480296]. [PubMed Central: PMC5414056].

  • 29.

    Dagur PK, McCoy JP Jr. Collection, storage, and preparation of human blood cells. Curr Protoc Cytom. 2015;73:5 1 1-16. doi: 10.1002/0471142956.cy0501s73. [PubMed: 26132177]. [PubMed Central: PMC4524540].

  • 30.

    Yeh ML, Huang CF, Hsieh MH, Ko YM, Chen KY, Liu TW, et al. Reactivation of hepatitis B in patients of chronic hepatitis C with hepatitis B virus infection treated with direct acting antivirals. J Gastroenterol Hepatol. 2017;32(10):1754-62. doi: 10.1111/jgh.13771. [PubMed: 28230928].

  • 31.

    Aggeletopoulou I, Konstantakis C, Manolakopoulos S, Triantos C. Risk of hepatitis B reactivation in patients treated with direct-acting antivirals for hepatitis C. World J Gastroenterol. 2017;23(24):4317-23. doi: 10.3748/wjg.v23.i24.4317. [PubMed: 28706414]. [PubMed Central: PMC5487495].

  • 32.

    Ranjbar M, Dadkhah M, Bokharaei Salim F, Daneshbodi M, Savaj S, Keyvani H. The prevalence of occult HBV infection among hemodialysis patients of Tehran, Iran. Mod Care J. 2017;14(4). doi: 10.5812/modernc.65546.

  • 33.

    Holmes JA, Yu ML, Chung RT. Hepatitis B reactivation during or after direct acting antiviral therapy - implication for susceptible individuals. Expert Opin Drug Saf. 2017;16(6):651-72. doi: 10.1080/14740338.2017.1325869. [PubMed: 28471314]. [PubMed Central: PMC5589072].

  • 34.

    Huang R, Yan X, Xia J, Wang J, Wu C. Letter: Hepatitis B virus reactivation in patients with chronic hepatitis C during direct-acting anti-viral therapy. Aliment Pharmacol Ther. 2017;45(12):1558. doi: 10.1111/apt.14080. [PubMed: 28503862].

  • 35.

    Fabbri G, Mastrorosa I, Vergori A, Mazzotta V, Pinnetti C, Grisetti S, et al. Reactivation of occult HBV infection in an HIV/HCV Co-infected patient successfully treated with sofosbuvir/ledipasvir: A case report and review of the literature. BMC Infect Dis. 2017;17(1):182. doi: 10.1186/s12879-017-2287-y. [PubMed: 28249574]. [PubMed Central: PMC5333431].

  • 36.

    Londono MC, Lens S, Marino Z, Bonacci M, Ariza X, Broquetas T, et al. Hepatitis B reactivation in patients with chronic hepatitis C undergoing anti-viral therapy with an interferon-free regimen. Aliment Pharmacol Ther. 2017;45(8):1156-61. doi: 10.1111/apt.13985. [PubMed: 28206681].

  • 37.

    Wang C, Ji D, Chen J, Shao Q, Li B, Liu J, et al. Hepatitis due to reactivation of hepatitis B virus in endemic areas among patients with hepatitis C treated with direct-acting antiviral agents. Clin Gastroenterol Hepatol. 2017;15(1):132-6. doi: 10.1016/j.cgh.2016.06.023. [PubMed: 27392759].

  • 38.

    Calvaruso V, Ferraro D, Licata A, Bavetta MG, Petta S, Bronte F, et al. HBV reactivation in patients with HCV/HBV cirrhosis on treatment with direct-acting antivirals. J Viral Hepat. 2018;25(1):72-9. doi: 10.1111/jvh.12754. [PubMed: 28703895].

  • 39.

    Tyson GL, Kramer JR, Duan Z, Davila JA, Richardson PA, El-Serag HB. Prevalence and predictors of hepatitis B virus coinfection in a United States cohort of hepatitis C virus-infected patients. Hepatology. 2013;58(2):538-45. doi: 10.1002/hep.26400. [PubMed: 23505059]. [PubMed Central: PMC3729715].

  • 40.

    Mekky MA, Nasr AM, Saleh MA, Wasif NK, Khalaf M, Aboalam H, et al. Virologic and histologic characterisation of dual hepatitis B and C co-infection in Egyptian patients. Arab J Gastroenterol. 2013;14(4):143-7. doi: 10.1016/j.ajg.2013.11.003. [PubMed: 24433642].

  • 41.

    Senturk H, Tahan V, Canbakan B, Uraz S, Ulger Y, Ozaras R, et al. Chronic hepatitis C responds poorly to combination therapy in chronic hepatis B carriers. Neth J Med. 2008;66(5):191-5. [PubMed: 18490796].

  • 42.

    Ozaras R, Mete B, Tabak F. Occult hepatitis B and risk of reactivation after hepatitis C treatment with direct-acting antivirals. Clin Gastroenterol Hepatol. 2017;15(4):605. doi: 10.1016/j.cgh.2016.11.030. [PubMed: 27923721].

  • 43.

    Kawagishi N, Suda G, Onozawa M, Kimura M, Maehara O, Ito J, et al. Hepatitis B virus reactivation during hepatitis C direct-acting antiviral therapy in patients with previous HBV infection. J Hepatol. 2017;67(5):1106-8. doi: 10.1016/j.jhep.2017.04.008. [PubMed: 28438688].

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