BACKGROUND The diagnosis and etiology of multiple primary malignant neoplasms(MPMNs)are difficult to establish.Here,we report a case of heterochronic triple primary malignancies with gastric cancer,nasopharyngeal squa...BACKGROUND The diagnosis and etiology of multiple primary malignant neoplasms(MPMNs)are difficult to establish.Here,we report a case of heterochronic triple primary malignancies with gastric cancer,nasopharyngeal squamous cell cancer,and then rectal cancer.CASE SUMMARY The patient was first diagnosed with gastric cancer at the age of 33 in 2014 and underwent distal gastrectomy and gastrojejunostomy and six cycles of adjuvant chemotherapy.Three years later,he was diagnosed with nasopharyngeal cancer and treated with radical chemoradiotherapy in 2017.Recently,a mass in the middle of the rectum was resected and reported as ulcerative,moderately to poorly differentiated adenocarcinoma.Research on the etiology of MPMNs showed that Epstein-Barr virus(EBV)infection may be the cause of gastric cancer and nasopharyngeal squamous cell cancer since these two primary lesions were positive for transcripts of EBV-encoded ribonucleic acid using an in situ hybridization EBV-encoded ribonucleic acid probe in formalin-fixed,paraffinembedded tissue.The cause of rectal cancer may be due to a somatic mutation of tumor protein 53 gene in exon 8(c.844C>T,p.Arg282Trp)through highthroughput sequencing for the rectal cancer.Appropriate standard therapy for each primary cancer was administered,and the patient has no evidence of cancer disease to date.CONCLUSION To our knowledge,this is the first report on heterochronic triple primary malignancies whose cause may be associated with EBV infection and tumor protein 53 genetic mutations.The etiological research may not only elucidate the cause of MPMN but also has implications in clinical management.展开更多
In this editorial we comment on the article published in the recent issue of the W orld Journal of Gastroenterology.We focus specifically on the problem of occult hepatitis B virus(HBV)infection,that is a result of pr...In this editorial we comment on the article published in the recent issue of the W orld Journal of Gastroenterology.We focus specifically on the problem of occult hepatitis B virus(HBV)infection,that is a result of previous hepatitis B(PHB)and a source for reactivation of HBV.The prevalence of PHB is underestimated due to the lack of population testing programs.However,this condition not only com-plicate anticancer treatment,but may be responsible for the development of other diseases,like cancer or autoimmune disorders.Here we unveil possible mecha-nisms responsible for realization of these processes and suggest practical approa-ches for diagnosis and treatment.展开更多
Background: Prevention is one of the safe schemes against the high prevalence of viral Hepatitis. Negative perceptions or perceptions about the risks of hepatitis B among medical students and health care workers may i...Background: Prevention is one of the safe schemes against the high prevalence of viral Hepatitis. Negative perceptions or perceptions about the risks of hepatitis B among medical students and health care workers may influence the behavioral pattern and adoption of preventive measures against the virus and can affect the uptake of the Hepatitis B vaccine. This study assesses the perception of medical students towards Hepatitis B virus infection and Hepatitis B Vaccination in a Private Tertiary Hospital in Jos North Local Government, Plateau State, Nigeria. Methods: This was a descriptive cross-sectional study done in August 2021 among 236 clinical medical students using a multistage sampling technique. Data was collected using an interviewer-administered structured questionnaire and analysed using the IBM SPSS 28 (Statistical Package for the Social Sciences). Ethical approval was granted by Bingham University Teaching Hospital, Ethics Committee, Jos, Plateau State. Results: Two-thirds of respondents were of the opinion that they are at risk of contracting HBV. Half were of the opinion that the risk is very much while a third believed the risk is moderate. Among those who think they are not at risk of contracting HBV, the majority felt so because they are vaccinated while 10.3% believe that they are safe. 43.2% of respondents think that HBV Vaccine is very effective in preventing HBV infection while 39.8% think it is slightly effective, and 7.6% think it is not effective. Almost all respondents, 99.2% are of the opinion that HBV Vaccination is important for students while 0.8% think it is not important. The majority of the respondents at 95.8% were willing to be screened for HBV. The majority (85.6%) of respondents are willing to pay for HBV Vaccine as against 14.4% of respondents who are not willing to pay. Conclusion: Summarily, 21 (8.9%) of the students had a negative perception of Hepatitis B Vaccination, and 215 (91.1%) had a positive perception of Hepatitis B Vaccination. Perception-sustaining events like seminars, workshops, road shows, and campaigns should be organized among students and health workers.展开更多
Occult hepatitis B infection(OBI), is characterized by low level hepatitis B virus(HBV) DNA in circulating blood and/or liver tissue. In clinical practice the presence of antibody to hepatitis B core antigen in hepati...Occult hepatitis B infection(OBI), is characterized by low level hepatitis B virus(HBV) DNA in circulating blood and/or liver tissue. In clinical practice the presence of antibody to hepatitis B core antigen in hepatitis B surface antigen(HBsAg)-/anti-HBs-negative subjects is considered indicative of OBI. OBI is mostly observed in the window period of acute HBV infection in blood donors and in recipients of blood and blood products, in hepatitis C virus chronic carriers, in patients under pharmacological immunosuppression, and in those with immunodepression due to HIV infection or cancer. Reactivation of OBI mostly occurs in anti-HIV-positive subjects, in patients treated with immunosuppressive therapy in onco-hematological settings, in patients who undergo hematopoietic stem cell transplantation, in those treated with anti-CD20 or anti-CD52 monoclonal antibody, or anti-tumor necrosis factors antibody for rheumatological diseases, or chemotherapy for solid tumors. Under these conditions the mortality rate for hepatic failure or progression of the underlying disease due to discontinuation of specific treatment can reach 20%. For patients with OBI, prophylaxis with nucleot(s)ide analogues should be based on the HBV serological markers, the underlying diseases and the type of immunosuppressive treatment. Lamivudine prophylaxis is indicated in hemopoietic stem cell transplantation and in onco-hematological diseases when high dose corticosteroids and rituximab are used; monitoring may be indicated when rituximab-sparing schedules are used, but early treatment should be applied as soon as HBsAg becomes detectable. This review article presents an up-to-date evaluation of the current knowledge on OBI.展开更多
BACKGROUND Occult hepatitis B infection(OBI)is characterized by the detection of hepatitis B virus(HBV)DNA in serum(usually HBV DNA<200 IU/mL)or the liver but negativity for hepatitis B surface antigen(HBsAg).The d...BACKGROUND Occult hepatitis B infection(OBI)is characterized by the detection of hepatitis B virus(HBV)DNA in serum(usually HBV DNA<200 IU/mL)or the liver but negativity for hepatitis B surface antigen(HBsAg).The diagnosis of OBI relies on the sensitivity of assays used in the detection of HBV DNA and HBsAg.HBsAg assays with inadequate sensitivity or inability to detect HBV S variants may lead to misdiagnosis of OBI in people with overt HBV infection.CASE SUMMARY We report a HBsAg-negative but hepatitis B envelope antigen-positive patient who had a significant HBV DNA level.The patient was initially diagnosed as having OBI.However,sequence analysis revealed a unique insertion of amino acid residues at positions 120-124 in the S protein,which affects the formation of a disulfide bond that is associated with the formation of a loop.It is well known that there is an overlap between the S protein and Pol protein.We found that this new insertion site occurred in polymerase/reverse transcriptase domain,indi-cating that this insertion might be involved in HBV pathogenicity.The patient was finally diagnosed with a false OBI.CONCLUSION An insertion of amino acid residues at positions 120-124 of the S protein affects the formation of immunodominant epitopes and results in negative HBsAg levels.展开更多
Hepatitis B virus(HBV)affects approximately two billion people worldwide and more than 240 million people in the world are currently chronic carrier that could develop serious complications in the future,like liver ci...Hepatitis B virus(HBV)affects approximately two billion people worldwide and more than 240 million people in the world are currently chronic carrier that could develop serious complications in the future,like liver cirrhosis and hepatocellular carcinoma.Although an extended HBV immunization program is being carried out since the early‘80s,representing effective preventive measure,leading to a dramatic reduction of HBV hepatitis incidence,globally HBV infection still represents a major public health problem.The HBV virus is a DNA virus belongs to the Hepadnaviridae family.The HBV-DNA is a circular,partial double strand genome.All coding information is on the minus DNA strand and it is organized into four open reading frames.Despite hepatitis B virus is a DNA virus,it has a high mutation rate due to its replicative strategy,that leads to the production of many nonidentical variants at each cycle of replication.In fact,it contains a polymerase without the proofreading activity,and uses an RNA intermediate(pg RNA)during its replication,so error frequencies are comparable to those seen in retroviruses and other RNA viruses rather than in more stable DNA viruses.Due to the low fidelity of the polymerase,the high replication rate and the overlapping reading frames,mutations occur throughout the genome and they have been identified both in the structural and not structural gene.The arise of mutations being to develop of a whole of viral variants called"quasi-species"and the prevalent population,which favors virus replication,was selected by viral fitness,host’s immune pressure and external pressure,i.e.,vaccination or antiviral therapy.Naturally occurring mutations were found both in acute and chronic subjects.In the present review we examine and discuss the most recent available data about HBV genetic variability and its significance.展开更多
Despite the availability of an effective vaccine, hepatitis B virus (HBV) infection remains a major health problem, with more than 350 million chronically infected people worldwide and over 1 million annual deaths due...Despite the availability of an effective vaccine, hepatitis B virus (HBV) infection remains a major health problem, with more than 350 million chronically infected people worldwide and over 1 million annual deaths due to cirrhosis and liver cancer. HBV mutations are primarily generated due both to a lack of proofreading capacity by HBV polymerase and to host immune pressure, which is a very important factor for predicting disease progression and therapeutic outcomes. Several types of HBV precore/core (preC/C) mutations have been described to date. The host immune response against T cells drives mutation in the preC/C region. Specifically, preC/C mutations in the MHC class II restricted region are more common than in other regions and are significantly related to hepatocellular carcinoma. Certain mutations, including preC G1896A, are also significantly related to HBeAg-negative chronic infection. This review article mainly focuses on the HBV preC/C mutations that are related to disease severity and on the HBeAg serostatus of chronically infected patients.展开更多
Chronic hepatitis B virus (HBV) infection remains a major health problem, with more than 240 million people chronically infected worldwide and potentially 650000 deaths per year due to advanced liver diseases includin...Chronic hepatitis B virus (HBV) infection remains a major health problem, with more than 240 million people chronically infected worldwide and potentially 650000 deaths per year due to advanced liver diseases including liver cirrhosis and hepatocellular carcinoma (HCC). HBV-X protein (HBx) contributes to the biology and pathogenesis of HBV via stimulating virus replication or altering host gene expression related to HCC. The HBV X region contains only 465 bp encoding the 16.5 kDa HBx protein, which also contains several critical cis-elements such as enhancer II, the core promoter and the microRNA-binding region. Thus, mutations in this region may affect not only the HBx open reading frame but also the overlapped cis-elements. Recently, several types of HBx mutations significantly associated with clinical severity have been described, although the functional mechanism in most of these cases remains unsolved. This review article will mainly focus on the HBx mutations proven to be significantly related to clinical severity via epidemiological studies.展开更多
AIM:To investigate the presence of mixed infection and discrepancy between hepatitis C virus(HCV) genotypes in plasma,peripheral blood mononuclear cells(PBMCs),and liver biopsy specimens.METHODS:From September 2008 up...AIM:To investigate the presence of mixed infection and discrepancy between hepatitis C virus(HCV) genotypes in plasma,peripheral blood mononuclear cells(PBMCs),and liver biopsy specimens.METHODS:From September 2008 up to April 2009,133 patients with chronic hepatitis C referred to Firouzgar Hospital for initiation of an antiviral therapy were recruited in the study.Five milliliters of peripheral blood was collected from each patient and liver biopsy was performed in those who gave consent or had indications.HCV genotyping was done using INNO-LiPATM HCV in serum,PBMCs,and liver biopsy specimens and then conf irmed by sequencing of 5'-UTR fragments.RESULTS:The mean age of patients was 30.3 ± 17.1 years.Multiple transfusion was seen in 124(93.2%) of patients.Multiple HCV genotypes were found in 3(2.3%) of 133 plasma samples,9(6.8%) of 133 PBMC samples,and 8(18.2%) of 44 liver biopsy specimens.It is notable that the different genotypes found in PBMCs were not the same as those found in plasma and liver biopsy specimens.CONCLUSION:Our study shows that a signif icant proportion of patients with chronic hepatitis C are affected by multiple HCV genotypes which may not be detectable only in serum of patients.展开更多
The systemic therapies available for the management of Psoriasis (PsO) patients who cannot be treated with more conservative options, such as topical agents and/or phototherapy, with the exception of acitretin, can wo...The systemic therapies available for the management of Psoriasis (PsO) patients who cannot be treated with more conservative options, such as topical agents and/or phototherapy, with the exception of acitretin, can worsen or reactivate a chronic infection. Therefore, before administering immunosuppressive therapies with either conventional disease-modifying drugs (cDMARDs) or biological ones (bDMARDs) it is mandatory to screen patients for some infections, including hepatitis B virus (HBV) and hepatitis C virus (HCV). In particular, the patients eligible to receive an immunosuppressive drug must be screened for the following markers: antibody to hepatitis B core, antibody to hepatitis B surface antigen (anti-HBsAg), HBsAg, and antibody to HCV (anti-HCV). In case HBV or HCV infection is diagnosed, a close collaboration with a consultant hepatologist is needed before and during an immunosuppressive therapy. Concerning therapy with immunosuppressive drugs in PsO patients with HBV or HCV infection, data exist mainly for cyclosporine a (CyA) or bDMARDs (etanercept, adalimumab, infliximab, ustekinumab). The natural history of HBV and HCV infection differs significantly as well as the effect of immunosuppression on the aforementioned infectious diseases. As a rule, in the case of active HBV infection, systemic immunosuppressive antipsoriatic therapies must be deferred until the infection is controlled with an adequate antiviral treatment. Inactive carriers need to receive antiviral prophylaxis 2-4 wk before starting immunosuppressive therapy, to be continued after 6-12 mo from its suspension. Due to the risk of HBV reactivation, these patients should be monitored monthly for the first 3 mo and then every 3 mo for HBV DNA load together with transaminases levels. Concerning the patients who are occult HBV carriers, the risk of HBV reactivation is very low. Therefore, these patients generally do not need antiviral prophylaxis and the sera HBsAg and transaminases dosing can be monitored every 3 mo. Concerning PsO patients with chronic HCV infection their management with immunosuppressive drugs is less problematic as compared to those infected by HBV. In fact, HCV reactivation is an extremely rare event after administration of drugs such as CyA or tumor necrosis factor-α inhibitors. As a rule, these patients can be monitored measuring HCV RNA load, and ALT, aspartate transaminase, gamma-glutamyl-transferase, bilirubin, alkaline phosphatase, albumin and platelet every 3-6 mo. The present article provides an updated overview based on more recently reported data on monitoring and managing PsO patients who need systemic antipsoriatic treatment and have HBV or HCV infection as comorbidity.展开更多
An amino acid mutation(R127→I) in the 3A non-structural protein of an FMDV serotype Asia1 rabbit-attenuated ZB strain was previously found after attenuation of the virus. To explore the effects of this mutation on vi...An amino acid mutation(R127→I) in the 3A non-structural protein of an FMDV serotype Asia1 rabbit-attenuated ZB strain was previously found after attenuation of the virus. To explore the effects of this mutation on viral replication and infection, the amino acid residue isoleucine(I) was changed to arginine(R) in the infectious cDNA clone of the rabbit-attenuated ZB strain by sitedirected mutagenesis, and the R127-mutated virus was rescued. BHK monolayer cells and suckling mice were inoculated with the R127-mutated virus to test its growth property and pathogenicity, respectively. The effects of the R127 mutation on viral replication and virulence were analyzed. The data showed that there was a slight difference in plaque morphology between the R127-mutated and wild-type viruses. The growth rate of the mutated virus was lower in BHK-21 cells and its virulence in suckling mice was also attenuated. This study indicates that the R127 mutation in 3A may play an important role in FMDV replication in vitro and in pathogenicity in suckling mice.展开更多
It is unclear whether immune escape-associated mutations in the major hydrophilic region of hepatitis B virus surface antigen(HBsAg)are associated with nucleoside/nucleotide analog resistance.AIM To evaluate the assoc...It is unclear whether immune escape-associated mutations in the major hydrophilic region of hepatitis B virus surface antigen(HBsAg)are associated with nucleoside/nucleotide analog resistance.AIM To evaluate the association between immune escape-associated mutations and nucleoside/nucleotide analog resistance mutations.METHODS In total,19440 patients with chronic hepatitis B virus infection,who underwent resistance testing at the Fifth Medical Center of Chinese PLA General Hospital between July 2007 and December 2017,were enrolled.As determined by sequence analysis,6982 patients harbored a virus with resistance mutations and 12458 harbored a virus lacking resistance mutations.Phenotypic analyses were performed to evaluate HBsAg production,replication capacity,and drug-induced viral inhibition of patient-derived drug-resistant mutants with or without the coexistence of sA159V.RESULTS The rate of immune escape-associated mutation was significantly higher in 9 of the 39 analyzed mutation sites in patients with resistance mutations than in patients without resistance mutations.In particular,these mutations were sQ101H/K/R,sS114A/L/T,sT118A/K/M/R/S/V,sP120A/L/Q/S/T,sT/I126A/N/P/S,sM133I/L/T,sC137W/Y,sG145A/R,and sA159G/V.Among these,sA159V was detected in 1.95%(136/6982)of patients with resistance mutations and 1.08%(134/12,458)of patients lacking resistance mutations(P<0.05).The coexistence of sA159V with lamivudine(LAM)and entecavir(ETV)-resistance mutations in the same viral genome was identified during follow-up in some patients with drug resistance.HBsAg production was significantly lower and the replication capacity was significantly higher,without a significant difference in LAM/ETV susceptibility,in sA159V-containing LAM/ETV-resistant mutants than in their sA159V-lacking counterparts.CONCLUSION In summary,we observed a close link between the increase in certain immune escape-associated mutations and the development of resistance mutations.sA159V might increase the fitness of LAM/ETV-resistant mutants under environmental pressure in some cases.展开更多
Hepatitis B virus (HBV)-related liver disease is the leading indication for liver transplantation (LT) in Asia,especially in China.With the introduction of hepatitis B immunoglobulin (HBIG) and oral antiviral drugs,th...Hepatitis B virus (HBV)-related liver disease is the leading indication for liver transplantation (LT) in Asia,especially in China.With the introduction of hepatitis B immunoglobulin (HBIG) and oral antiviral drugs,the recurrent HBV infection rate after LT has been evidently reduced.However,complete eradication of recurrent HBV infection after LT is almost impossible.Recurrent graft infection may lead to rapid disease progression and is a frequent cause of death within the fi rst year after LT.At present,the availability of new oral medications,especially nucleoside or nucleotide analogues such as adefovir dipivoxil,entecavir and tenofovir disoproxil fumarate,further strengthens our ability to treat recurrent HBV infection after LT.Moreover,since combined treatment with HBIG and antiviral agents after liver re-transplantation may play an important role in improving the prognosis of recurrent HBV infection,irreversible graft dysfunction secondary to recurrent HBV infection in spite of oral medications should no longer be considered an absolute contraindication for liver re-transplantation.Published reviews focusing on the therapeutic strategies for recurrent HBV infection after LT are very limited.In this article,the current therapeutic strategies for recurrent HBV infection after LT and evolving new trends are reviewed to guide clinical doctors to choose an optimal treatment plan in different clinical settings.展开更多
Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replic...Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our understanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome.展开更多
Occult hepatitis B infection(OBI) is characterized by hepatitis B virus(HBV) DNA in serum in the absence of hepatitis B surface antigen(HBsAg) presenting HBsAg-negative and anti-HBc positive serological patterns.Occul...Occult hepatitis B infection(OBI) is characterized by hepatitis B virus(HBV) DNA in serum in the absence of hepatitis B surface antigen(HBsAg) presenting HBsAg-negative and anti-HBc positive serological patterns.Occult HBV status is associated in some cases with mutant viruses undetectable by HBsAg assays;but more frequently it is due to a strong suppression of viral replication and gene expression.OBI is an entity with world-wide diffusion.The failure to detect HBsAg,despite the persistence of the viral DNA,is due in most cases to the strong suppression of viral replication and gene expression that characterizes this"occult"HBV infection;although the mechanisms responsible for suppression of HBV are not well understood.The majority of OBI cases are secondary to overt HBV infection and represent a residual low viremia level suppressed by a strong immune response together with histological derangements which occurred during acute or chronic HBV infection.Much evidence suggests that it can favour the progression of liver fibrosis and the development of hepatocellular carcinoma.展开更多
Hepatitis B is caused by the host immune response and T cells play a major role in the immunopathogenesis. More importantly,T cells not only destroy hepatocytes infected by hepatitis B virus(HBV),but also control HBV ...Hepatitis B is caused by the host immune response and T cells play a major role in the immunopathogenesis. More importantly,T cells not only destroy hepatocytes infected by hepatitis B virus(HBV),but also control HBV replication or eradicate HBV in a noncytolytic manner.Therefore,analysis of T cell immune response during acute and chronic HBV infection is important to develop a strategy for successful viral control,which could lead to immunotherapy for terminating persistent HBV infection.There have been many attempts at immunotherapy for chronic HBV infection,and some have shown promising results.High viral load has been shown to suppress antiviral immune responses and immunoinhibitory signals have been recently elucidated, therefore,viral suppression by nucleos(t)ide analogs, stimulation of antiviral immune response,and suppression of the immunoinhibitory signals must be combined to achieve desirable antiviral effects.展开更多
Occult hepatitis B virus(HBV) infection(OBI) is characterized by the persistence of HBV DNA in the liver tissue in individuals negative for the HBV surface antigen.The prevalence of OBI is quite variable depending on ...Occult hepatitis B virus(HBV) infection(OBI) is characterized by the persistence of HBV DNA in the liver tissue in individuals negative for the HBV surface antigen.The prevalence of OBI is quite variable depending on the level of endemic disease in different parts of the world,the different assays utilized in the studies,and the different populations studied.Many studies have been carried out on OBI prevalence in different areas of the world and categories of individuals.The studies show that OBI prevalence seems to be higher among subjects at high risk for HBV infection and with liver disease than among individuals at low risk of infection and without liver disease.展开更多
In 2008,the European Association for the study of the liver(EASL) defined occult hepatitis B virus infection (OBI) as the"presence of hepatitis B virus(HBV) DNA in the liver(with detectable or undetectable HBV DN...In 2008,the European Association for the study of the liver(EASL) defined occult hepatitis B virus infection (OBI) as the"presence of hepatitis B virus(HBV) DNA in the liver(with detectable or undetectable HBV DNA in the serum) of individuals testing hepatitis B surface antigen(HBsAg) negative by currently available assays".Several aspects of occult HBV infection are still poorly understood,including the definition itself and a standardized approach for laboratory-based detection,which is the purpose of this review.The clinical significance of OBI has not yet been established;however,in terms of public health,the clinical importance arises from the risk of HBV transmission.Consequently,it is important to detect high-risk groups for occult HBV infection to prevent transmission.The main issue is,perhaps,to identify the target population for screening OBI.Viremia is very low or undetectable in occult HBV infection,even when the most sensitive methods are used,and the detection of the viral DNA reservoir in hepatocytes would provide the best evaluation of occult HBV prevalence in a defined set of patients.However,this diagnostic approach is obviously unsuitable:blood detection of occult hepatitis B requires assays of the highest sensitivity and specificity with a lower limit of detection<10 IU/mL for HBV DNA and<0.1 ng/mL for HBsAg.展开更多
Pegylated interferon α (IFNα) in combination with ribavirin is currently recommended as a standard-of-care treatment for chronic hepatitis C virus (HCV) infection. This combination therapy has drastically improved t...Pegylated interferon α (IFNα) in combination with ribavirin is currently recommended as a standard-of-care treatment for chronic hepatitis C virus (HCV) infection. This combination therapy has drastically improved the rate of sustained virological response, specifically in difficult-to-treat patients. Recently, individualized treatment, such as response-guided therapy, is being developed based on host-, HCV- and treatment-related factors. Furthermore, modified regimens with currently available medications, novel modified IFNα and ribavirin or combinations with specifically targeted antiviral therapy for HCV agents, are currently being investigated. The purpose of this review is to address some issues and epoch-making topics in the treatment of chronic HCV infection, and to discuss more optimal and highly individualized therapeutic strategies for HCV-infected patients.展开更多
AIM: To investigate the responses of TT virus (TTV) and hepatitis B virus (HBV) to a long-term lamivudine therapy.METHODS: Sixteen patients infected with both TTV and HBV were treated with lamivudine 100 mg daily for ...AIM: To investigate the responses of TT virus (TTV) and hepatitis B virus (HBV) to a long-term lamivudine therapy.METHODS: Sixteen patients infected with both TTV and HBV were treated with lamivudine 100 mg daily for 30 months. Blood samples were drawn at the beginning of the therapy and subsequently at month 3, 6, 9, 12 and 30.Serum TTV was quantified by real time PCR and serum HBV was detected by hybridization assay and nested polymerase chain reaction.RESULTS: TTV infection was detected in 100 % of HBV-infected patients. Loss of serum TTV DNA after one year of treatment occurred in 1/16 (6 %) patients. At the end of therapy, TTV DNA was positive in 94 % of them. The decline of HBV viremia was evident at 3 months after therapy and the response rate was 31%, 44 %, 63 %, 50 % and 50 %at month 3, 6, 9, 12 and 30, respectively.CONCLUSION: TTV replication is not sensitive to lamivudine and is highly prevalent in HBV-infected patients.展开更多
文摘BACKGROUND The diagnosis and etiology of multiple primary malignant neoplasms(MPMNs)are difficult to establish.Here,we report a case of heterochronic triple primary malignancies with gastric cancer,nasopharyngeal squamous cell cancer,and then rectal cancer.CASE SUMMARY The patient was first diagnosed with gastric cancer at the age of 33 in 2014 and underwent distal gastrectomy and gastrojejunostomy and six cycles of adjuvant chemotherapy.Three years later,he was diagnosed with nasopharyngeal cancer and treated with radical chemoradiotherapy in 2017.Recently,a mass in the middle of the rectum was resected and reported as ulcerative,moderately to poorly differentiated adenocarcinoma.Research on the etiology of MPMNs showed that Epstein-Barr virus(EBV)infection may be the cause of gastric cancer and nasopharyngeal squamous cell cancer since these two primary lesions were positive for transcripts of EBV-encoded ribonucleic acid using an in situ hybridization EBV-encoded ribonucleic acid probe in formalin-fixed,paraffinembedded tissue.The cause of rectal cancer may be due to a somatic mutation of tumor protein 53 gene in exon 8(c.844C>T,p.Arg282Trp)through highthroughput sequencing for the rectal cancer.Appropriate standard therapy for each primary cancer was administered,and the patient has no evidence of cancer disease to date.CONCLUSION To our knowledge,this is the first report on heterochronic triple primary malignancies whose cause may be associated with EBV infection and tumor protein 53 genetic mutations.The etiological research may not only elucidate the cause of MPMN but also has implications in clinical management.
基金Supported by Ministry of Science and Higher education of Russia,No.FGMF-2022-0005Moscow Healthcare Department,No.123040700014-4.
文摘In this editorial we comment on the article published in the recent issue of the W orld Journal of Gastroenterology.We focus specifically on the problem of occult hepatitis B virus(HBV)infection,that is a result of previous hepatitis B(PHB)and a source for reactivation of HBV.The prevalence of PHB is underestimated due to the lack of population testing programs.However,this condition not only com-plicate anticancer treatment,but may be responsible for the development of other diseases,like cancer or autoimmune disorders.Here we unveil possible mecha-nisms responsible for realization of these processes and suggest practical approa-ches for diagnosis and treatment.
文摘Background: Prevention is one of the safe schemes against the high prevalence of viral Hepatitis. Negative perceptions or perceptions about the risks of hepatitis B among medical students and health care workers may influence the behavioral pattern and adoption of preventive measures against the virus and can affect the uptake of the Hepatitis B vaccine. This study assesses the perception of medical students towards Hepatitis B virus infection and Hepatitis B Vaccination in a Private Tertiary Hospital in Jos North Local Government, Plateau State, Nigeria. Methods: This was a descriptive cross-sectional study done in August 2021 among 236 clinical medical students using a multistage sampling technique. Data was collected using an interviewer-administered structured questionnaire and analysed using the IBM SPSS 28 (Statistical Package for the Social Sciences). Ethical approval was granted by Bingham University Teaching Hospital, Ethics Committee, Jos, Plateau State. Results: Two-thirds of respondents were of the opinion that they are at risk of contracting HBV. Half were of the opinion that the risk is very much while a third believed the risk is moderate. Among those who think they are not at risk of contracting HBV, the majority felt so because they are vaccinated while 10.3% believe that they are safe. 43.2% of respondents think that HBV Vaccine is very effective in preventing HBV infection while 39.8% think it is slightly effective, and 7.6% think it is not effective. Almost all respondents, 99.2% are of the opinion that HBV Vaccination is important for students while 0.8% think it is not important. The majority of the respondents at 95.8% were willing to be screened for HBV. The majority (85.6%) of respondents are willing to pay for HBV Vaccine as against 14.4% of respondents who are not willing to pay. Conclusion: Summarily, 21 (8.9%) of the students had a negative perception of Hepatitis B Vaccination, and 215 (91.1%) had a positive perception of Hepatitis B Vaccination. Perception-sustaining events like seminars, workshops, road shows, and campaigns should be organized among students and health workers.
文摘Occult hepatitis B infection(OBI), is characterized by low level hepatitis B virus(HBV) DNA in circulating blood and/or liver tissue. In clinical practice the presence of antibody to hepatitis B core antigen in hepatitis B surface antigen(HBsAg)-/anti-HBs-negative subjects is considered indicative of OBI. OBI is mostly observed in the window period of acute HBV infection in blood donors and in recipients of blood and blood products, in hepatitis C virus chronic carriers, in patients under pharmacological immunosuppression, and in those with immunodepression due to HIV infection or cancer. Reactivation of OBI mostly occurs in anti-HIV-positive subjects, in patients treated with immunosuppressive therapy in onco-hematological settings, in patients who undergo hematopoietic stem cell transplantation, in those treated with anti-CD20 or anti-CD52 monoclonal antibody, or anti-tumor necrosis factors antibody for rheumatological diseases, or chemotherapy for solid tumors. Under these conditions the mortality rate for hepatic failure or progression of the underlying disease due to discontinuation of specific treatment can reach 20%. For patients with OBI, prophylaxis with nucleot(s)ide analogues should be based on the HBV serological markers, the underlying diseases and the type of immunosuppressive treatment. Lamivudine prophylaxis is indicated in hemopoietic stem cell transplantation and in onco-hematological diseases when high dose corticosteroids and rituximab are used; monitoring may be indicated when rituximab-sparing schedules are used, but early treatment should be applied as soon as HBsAg becomes detectable. This review article presents an up-to-date evaluation of the current knowledge on OBI.
基金Supported by the Shanghai Municipal Commission of Health and Family Planning,No.PKJ2018-Y05.
文摘BACKGROUND Occult hepatitis B infection(OBI)is characterized by the detection of hepatitis B virus(HBV)DNA in serum(usually HBV DNA<200 IU/mL)or the liver but negativity for hepatitis B surface antigen(HBsAg).The diagnosis of OBI relies on the sensitivity of assays used in the detection of HBV DNA and HBsAg.HBsAg assays with inadequate sensitivity or inability to detect HBV S variants may lead to misdiagnosis of OBI in people with overt HBV infection.CASE SUMMARY We report a HBsAg-negative but hepatitis B envelope antigen-positive patient who had a significant HBV DNA level.The patient was initially diagnosed as having OBI.However,sequence analysis revealed a unique insertion of amino acid residues at positions 120-124 in the S protein,which affects the formation of a disulfide bond that is associated with the formation of a loop.It is well known that there is an overlap between the S protein and Pol protein.We found that this new insertion site occurred in polymerase/reverse transcriptase domain,indi-cating that this insertion might be involved in HBV pathogenicity.The patient was finally diagnosed with a false OBI.CONCLUSION An insertion of amino acid residues at positions 120-124 of the S protein affects the formation of immunodominant epitopes and results in negative HBsAg levels.
文摘Hepatitis B virus(HBV)affects approximately two billion people worldwide and more than 240 million people in the world are currently chronic carrier that could develop serious complications in the future,like liver cirrhosis and hepatocellular carcinoma.Although an extended HBV immunization program is being carried out since the early‘80s,representing effective preventive measure,leading to a dramatic reduction of HBV hepatitis incidence,globally HBV infection still represents a major public health problem.The HBV virus is a DNA virus belongs to the Hepadnaviridae family.The HBV-DNA is a circular,partial double strand genome.All coding information is on the minus DNA strand and it is organized into four open reading frames.Despite hepatitis B virus is a DNA virus,it has a high mutation rate due to its replicative strategy,that leads to the production of many nonidentical variants at each cycle of replication.In fact,it contains a polymerase without the proofreading activity,and uses an RNA intermediate(pg RNA)during its replication,so error frequencies are comparable to those seen in retroviruses and other RNA viruses rather than in more stable DNA viruses.Due to the low fidelity of the polymerase,the high replication rate and the overlapping reading frames,mutations occur throughout the genome and they have been identified both in the structural and not structural gene.The arise of mutations being to develop of a whole of viral variants called"quasi-species"and the prevalent population,which favors virus replication,was selected by viral fitness,host’s immune pressure and external pressure,i.e.,vaccination or antiviral therapy.Naturally occurring mutations were found both in acute and chronic subjects.In the present review we examine and discuss the most recent available data about HBV genetic variability and its significance.
基金Supported by A National Research Foundation grant of Ministry of Science, ICT and Future Planning, South Korea, No. NRF-2015R1C1A1A02037267a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute, the Ministry of Health and Welfare, South Korea, No. HI14C0955
文摘Despite the availability of an effective vaccine, hepatitis B virus (HBV) infection remains a major health problem, with more than 350 million chronically infected people worldwide and over 1 million annual deaths due to cirrhosis and liver cancer. HBV mutations are primarily generated due both to a lack of proofreading capacity by HBV polymerase and to host immune pressure, which is a very important factor for predicting disease progression and therapeutic outcomes. Several types of HBV precore/core (preC/C) mutations have been described to date. The host immune response against T cells drives mutation in the preC/C region. Specifically, preC/C mutations in the MHC class II restricted region are more common than in other regions and are significantly related to hepatocellular carcinoma. Certain mutations, including preC G1896A, are also significantly related to HBeAg-negative chronic infection. This review article mainly focuses on the HBV preC/C mutations that are related to disease severity and on the HBeAg serostatus of chronically infected patients.
基金Supported by National Research Foundation grant of Ministry of Science,ICT and Future Planning,South Korea,No.NRF-2015R1C1A1A02037267Korea Health Technology R&D Project through the Korea Health Industry Development Institute,funded by the Ministry of Health and Welfare,South Korea,No.HI14C0955
文摘Chronic hepatitis B virus (HBV) infection remains a major health problem, with more than 240 million people chronically infected worldwide and potentially 650000 deaths per year due to advanced liver diseases including liver cirrhosis and hepatocellular carcinoma (HCC). HBV-X protein (HBx) contributes to the biology and pathogenesis of HBV via stimulating virus replication or altering host gene expression related to HCC. The HBV X region contains only 465 bp encoding the 16.5 kDa HBx protein, which also contains several critical cis-elements such as enhancer II, the core promoter and the microRNA-binding region. Thus, mutations in this region may affect not only the HBx open reading frame but also the overlapped cis-elements. Recently, several types of HBx mutations significantly associated with clinical severity have been described, although the functional mechanism in most of these cases remains unsolved. This review article will mainly focus on the HBx mutations proven to be significantly related to clinical severity via epidemiological studies.
基金Supported by Local Fund from Iran University of Medical Sciences
文摘AIM:To investigate the presence of mixed infection and discrepancy between hepatitis C virus(HCV) genotypes in plasma,peripheral blood mononuclear cells(PBMCs),and liver biopsy specimens.METHODS:From September 2008 up to April 2009,133 patients with chronic hepatitis C referred to Firouzgar Hospital for initiation of an antiviral therapy were recruited in the study.Five milliliters of peripheral blood was collected from each patient and liver biopsy was performed in those who gave consent or had indications.HCV genotyping was done using INNO-LiPATM HCV in serum,PBMCs,and liver biopsy specimens and then conf irmed by sequencing of 5'-UTR fragments.RESULTS:The mean age of patients was 30.3 ± 17.1 years.Multiple transfusion was seen in 124(93.2%) of patients.Multiple HCV genotypes were found in 3(2.3%) of 133 plasma samples,9(6.8%) of 133 PBMC samples,and 8(18.2%) of 44 liver biopsy specimens.It is notable that the different genotypes found in PBMCs were not the same as those found in plasma and liver biopsy specimens.CONCLUSION:Our study shows that a signif icant proportion of patients with chronic hepatitis C are affected by multiple HCV genotypes which may not be detectable only in serum of patients.
文摘The systemic therapies available for the management of Psoriasis (PsO) patients who cannot be treated with more conservative options, such as topical agents and/or phototherapy, with the exception of acitretin, can worsen or reactivate a chronic infection. Therefore, before administering immunosuppressive therapies with either conventional disease-modifying drugs (cDMARDs) or biological ones (bDMARDs) it is mandatory to screen patients for some infections, including hepatitis B virus (HBV) and hepatitis C virus (HCV). In particular, the patients eligible to receive an immunosuppressive drug must be screened for the following markers: antibody to hepatitis B core, antibody to hepatitis B surface antigen (anti-HBsAg), HBsAg, and antibody to HCV (anti-HCV). In case HBV or HCV infection is diagnosed, a close collaboration with a consultant hepatologist is needed before and during an immunosuppressive therapy. Concerning therapy with immunosuppressive drugs in PsO patients with HBV or HCV infection, data exist mainly for cyclosporine a (CyA) or bDMARDs (etanercept, adalimumab, infliximab, ustekinumab). The natural history of HBV and HCV infection differs significantly as well as the effect of immunosuppression on the aforementioned infectious diseases. As a rule, in the case of active HBV infection, systemic immunosuppressive antipsoriatic therapies must be deferred until the infection is controlled with an adequate antiviral treatment. Inactive carriers need to receive antiviral prophylaxis 2-4 wk before starting immunosuppressive therapy, to be continued after 6-12 mo from its suspension. Due to the risk of HBV reactivation, these patients should be monitored monthly for the first 3 mo and then every 3 mo for HBV DNA load together with transaminases levels. Concerning the patients who are occult HBV carriers, the risk of HBV reactivation is very low. Therefore, these patients generally do not need antiviral prophylaxis and the sera HBsAg and transaminases dosing can be monitored every 3 mo. Concerning PsO patients with chronic HCV infection their management with immunosuppressive drugs is less problematic as compared to those infected by HBV. In fact, HCV reactivation is an extremely rare event after administration of drugs such as CyA or tumor necrosis factor-α inhibitors. As a rule, these patients can be monitored measuring HCV RNA load, and ALT, aspartate transaminase, gamma-glutamyl-transferase, bilirubin, alkaline phosphatase, albumin and platelet every 3-6 mo. The present article provides an updated overview based on more recently reported data on monitoring and managing PsO patients who need systemic antipsoriatic treatment and have HBV or HCV infection as comorbidity.
基金jointly supported by grants from National Natural Science Foundation of China(No.31060343)Innovative Talents in Science and Technology Project of Yunnan Province(2011HB035)
文摘An amino acid mutation(R127→I) in the 3A non-structural protein of an FMDV serotype Asia1 rabbit-attenuated ZB strain was previously found after attenuation of the virus. To explore the effects of this mutation on viral replication and infection, the amino acid residue isoleucine(I) was changed to arginine(R) in the infectious cDNA clone of the rabbit-attenuated ZB strain by sitedirected mutagenesis, and the R127-mutated virus was rescued. BHK monolayer cells and suckling mice were inoculated with the R127-mutated virus to test its growth property and pathogenicity, respectively. The effects of the R127 mutation on viral replication and virulence were analyzed. The data showed that there was a slight difference in plaque morphology between the R127-mutated and wild-type viruses. The growth rate of the mutated virus was lower in BHK-21 cells and its virulence in suckling mice was also attenuated. This study indicates that the R127 mutation in 3A may play an important role in FMDV replication in vitro and in pathogenicity in suckling mice.
基金the National Natural Science Foundation of China,No.81572010,No.81671399,No.81721002 and No.81971329the Capital Health Research and Development of Special Fund Program,No.2016-2-5032and the Beijing Natural Science Foundation No.7172206.
文摘It is unclear whether immune escape-associated mutations in the major hydrophilic region of hepatitis B virus surface antigen(HBsAg)are associated with nucleoside/nucleotide analog resistance.AIM To evaluate the association between immune escape-associated mutations and nucleoside/nucleotide analog resistance mutations.METHODS In total,19440 patients with chronic hepatitis B virus infection,who underwent resistance testing at the Fifth Medical Center of Chinese PLA General Hospital between July 2007 and December 2017,were enrolled.As determined by sequence analysis,6982 patients harbored a virus with resistance mutations and 12458 harbored a virus lacking resistance mutations.Phenotypic analyses were performed to evaluate HBsAg production,replication capacity,and drug-induced viral inhibition of patient-derived drug-resistant mutants with or without the coexistence of sA159V.RESULTS The rate of immune escape-associated mutation was significantly higher in 9 of the 39 analyzed mutation sites in patients with resistance mutations than in patients without resistance mutations.In particular,these mutations were sQ101H/K/R,sS114A/L/T,sT118A/K/M/R/S/V,sP120A/L/Q/S/T,sT/I126A/N/P/S,sM133I/L/T,sC137W/Y,sG145A/R,and sA159G/V.Among these,sA159V was detected in 1.95%(136/6982)of patients with resistance mutations and 1.08%(134/12,458)of patients lacking resistance mutations(P<0.05).The coexistence of sA159V with lamivudine(LAM)and entecavir(ETV)-resistance mutations in the same viral genome was identified during follow-up in some patients with drug resistance.HBsAg production was significantly lower and the replication capacity was significantly higher,without a significant difference in LAM/ETV susceptibility,in sA159V-containing LAM/ETV-resistant mutants than in their sA159V-lacking counterparts.CONCLUSION In summary,we observed a close link between the increase in certain immune escape-associated mutations and the development of resistance mutations.sA159V might increase the fitness of LAM/ETV-resistant mutants under environmental pressure in some cases.
文摘Hepatitis B virus (HBV)-related liver disease is the leading indication for liver transplantation (LT) in Asia,especially in China.With the introduction of hepatitis B immunoglobulin (HBIG) and oral antiviral drugs,the recurrent HBV infection rate after LT has been evidently reduced.However,complete eradication of recurrent HBV infection after LT is almost impossible.Recurrent graft infection may lead to rapid disease progression and is a frequent cause of death within the fi rst year after LT.At present,the availability of new oral medications,especially nucleoside or nucleotide analogues such as adefovir dipivoxil,entecavir and tenofovir disoproxil fumarate,further strengthens our ability to treat recurrent HBV infection after LT.Moreover,since combined treatment with HBIG and antiviral agents after liver re-transplantation may play an important role in improving the prognosis of recurrent HBV infection,irreversible graft dysfunction secondary to recurrent HBV infection in spite of oral medications should no longer be considered an absolute contraindication for liver re-transplantation.Published reviews focusing on the therapeutic strategies for recurrent HBV infection after LT are very limited.In this article,the current therapeutic strategies for recurrent HBV infection after LT and evolving new trends are reviewed to guide clinical doctors to choose an optimal treatment plan in different clinical settings.
文摘Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our understanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome.
文摘Occult hepatitis B infection(OBI) is characterized by hepatitis B virus(HBV) DNA in serum in the absence of hepatitis B surface antigen(HBsAg) presenting HBsAg-negative and anti-HBc positive serological patterns.Occult HBV status is associated in some cases with mutant viruses undetectable by HBsAg assays;but more frequently it is due to a strong suppression of viral replication and gene expression.OBI is an entity with world-wide diffusion.The failure to detect HBsAg,despite the persistence of the viral DNA,is due in most cases to the strong suppression of viral replication and gene expression that characterizes this"occult"HBV infection;although the mechanisms responsible for suppression of HBV are not well understood.The majority of OBI cases are secondary to overt HBV infection and represent a residual low viremia level suppressed by a strong immune response together with histological derangements which occurred during acute or chronic HBV infection.Much evidence suggests that it can favour the progression of liver fibrosis and the development of hepatocellular carcinoma.
文摘Hepatitis B is caused by the host immune response and T cells play a major role in the immunopathogenesis. More importantly,T cells not only destroy hepatocytes infected by hepatitis B virus(HBV),but also control HBV replication or eradicate HBV in a noncytolytic manner.Therefore,analysis of T cell immune response during acute and chronic HBV infection is important to develop a strategy for successful viral control,which could lead to immunotherapy for terminating persistent HBV infection.There have been many attempts at immunotherapy for chronic HBV infection,and some have shown promising results.High viral load has been shown to suppress antiviral immune responses and immunoinhibitory signals have been recently elucidated, therefore,viral suppression by nucleos(t)ide analogs, stimulation of antiviral immune response,and suppression of the immunoinhibitory signals must be combined to achieve desirable antiviral effects.
文摘Occult hepatitis B virus(HBV) infection(OBI) is characterized by the persistence of HBV DNA in the liver tissue in individuals negative for the HBV surface antigen.The prevalence of OBI is quite variable depending on the level of endemic disease in different parts of the world,the different assays utilized in the studies,and the different populations studied.Many studies have been carried out on OBI prevalence in different areas of the world and categories of individuals.The studies show that OBI prevalence seems to be higher among subjects at high risk for HBV infection and with liver disease than among individuals at low risk of infection and without liver disease.
文摘In 2008,the European Association for the study of the liver(EASL) defined occult hepatitis B virus infection (OBI) as the"presence of hepatitis B virus(HBV) DNA in the liver(with detectable or undetectable HBV DNA in the serum) of individuals testing hepatitis B surface antigen(HBsAg) negative by currently available assays".Several aspects of occult HBV infection are still poorly understood,including the definition itself and a standardized approach for laboratory-based detection,which is the purpose of this review.The clinical significance of OBI has not yet been established;however,in terms of public health,the clinical importance arises from the risk of HBV transmission.Consequently,it is important to detect high-risk groups for occult HBV infection to prevent transmission.The main issue is,perhaps,to identify the target population for screening OBI.Viremia is very low or undetectable in occult HBV infection,even when the most sensitive methods are used,and the detection of the viral DNA reservoir in hepatocytes would provide the best evaluation of occult HBV prevalence in a defined set of patients.However,this diagnostic approach is obviously unsuitable:blood detection of occult hepatitis B requires assays of the highest sensitivity and specificity with a lower limit of detection<10 IU/mL for HBV DNA and<0.1 ng/mL for HBsAg.
文摘Pegylated interferon α (IFNα) in combination with ribavirin is currently recommended as a standard-of-care treatment for chronic hepatitis C virus (HCV) infection. This combination therapy has drastically improved the rate of sustained virological response, specifically in difficult-to-treat patients. Recently, individualized treatment, such as response-guided therapy, is being developed based on host-, HCV- and treatment-related factors. Furthermore, modified regimens with currently available medications, novel modified IFNα and ribavirin or combinations with specifically targeted antiviral therapy for HCV agents, are currently being investigated. The purpose of this review is to address some issues and epoch-making topics in the treatment of chronic HCV infection, and to discuss more optimal and highly individualized therapeutic strategies for HCV-infected patients.
基金Fundacion Manchega de Investigaciony Docencia en Gastroenterologia
文摘AIM: To investigate the responses of TT virus (TTV) and hepatitis B virus (HBV) to a long-term lamivudine therapy.METHODS: Sixteen patients infected with both TTV and HBV were treated with lamivudine 100 mg daily for 30 months. Blood samples were drawn at the beginning of the therapy and subsequently at month 3, 6, 9, 12 and 30.Serum TTV was quantified by real time PCR and serum HBV was detected by hybridization assay and nested polymerase chain reaction.RESULTS: TTV infection was detected in 100 % of HBV-infected patients. Loss of serum TTV DNA after one year of treatment occurred in 1/16 (6 %) patients. At the end of therapy, TTV DNA was positive in 94 % of them. The decline of HBV viremia was evident at 3 months after therapy and the response rate was 31%, 44 %, 63 %, 50 % and 50 %at month 3, 6, 9, 12 and 30, respectively.CONCLUSION: TTV replication is not sensitive to lamivudine and is highly prevalent in HBV-infected patients.