Real-life effectiveness and safety of sofosbuvir/velpatasvir/voxilaprevir in hepatitis C patients with previous DAA failure.

BACKGROUND & AIMS: Sofosbuvir/velpatasivr/voxilaprevir (SOF/VEL/VOX) is approved for retreatment of patients with HCV and a previous failure on direct-acting antivirals (DAAs), however real-life data are limited. The aim of this study was to assess the effectiveness and safety of SOF/VEL/VOX in a real-life setting. METHODS: All consecutive patients with HCV receiving SOF/VEL/VOX between May-October 2018 in 27 centers in Northern Italy were enrolled. Bridging fibrosis (F3) and cirrhosis (F4) were diagnosed by liver stiffness measurement: >10 and >13 kPa respectively. Sustained virological response (SVR) was defined as undetectable HCV-RNA 4 (SVR4) or 12 (SVR12) weeks after the end-of-treatment. RESULTS: A total of 179 patients were included: median age 57 (18-88) years, 74% males, median HCV-RNA 1,081,817 (482-25,590,000) IU/ml. Fibrosis stage was F0-F2 in 32%, F3 in 21%, F4 in 44%. HCV genotype was 1 in 58% (1b 33%, 1a 24%, 1nc 1%), 2 in 10%, 3 in 23% and 4 in 9%; 82% of patients carried resistance-associated substitutions in the NS3, NS5A or NS5B regions. Patients received SOF/VEL/VOX for 12 weeks, ribavirin was added in 22% of treatment schedules. Undetectable HCV-RNA was achieved by 74% of patients at week 4 and by 99% at week 12. Overall, 162/179 (91%) patients by intention to treat analysis and 162/169 (96%) by per protocol analysis achieved SVR12, respectively; treatment failures included 6 relapsers and 1 virological non-responder. Cirrhosis (p = 0.005) and hepatocellular carcinoma (p = 0.02) were the only predictors of treatment failure. Most frequent adverse events included fatigue (6%), hyperbilirubinemia (6%) and anemia (4%). CONCLUSIONS: SOF/VEL/VOX is an effective and safe retreatment for patients with HCV who have failed on a previous DAA course in a real-life setting. LAY SUMMARY: This is the largest European real-life study evaluating effectiveness and safety of sofosbuvir/velpatasvir/voxilaprevir (SOF/VEL/VOX) in a large cohort of consecutive patients with hepatitis C virus infection and a prior direct-acting antiviral failure, who were treated within the NAVIGATORE Lombardia and Veneto Networks, in Italy. This study demonstrated excellent effectiveness (98% and 96% sustained virological response rates at week 4 and 12, respectively) and an optimal safety profile of SOF/VEL/VOX. Cirrhosis and hepatocellular carcinoma onset were the only features associated with treatment failure.

Interferon-free antiviral treatment in B-cell lymphoproliferative disorders associated with hepatitis C virus infection.

Regression of hepatitis C virus (HCV)-associated lymphoma with interferon (IFN)-based antiviral treatment supports an etiological link between lymphoma and HCV infection. In addition, a favorable impact of antiviral treatment on overall survival of patients with HCV-related lymphoma has been reported. Data on IFN-free regimens combining direct-acting antivirals (DAAs) in HCV-associated lymphoproliferative disorders are scanty. We analyzed the virological and lymphoproliferative disease response (LDR) of 46 patients with indolent B-cell non-Hodgkin lymphomas (NHLs) or chronic lymphocytic leukemia (CLL) and chronic HCV infection treated with DAAs. The histological distribution was 37 marginal zone lymphomas (MZLs), 2 lymphoplasmacytic lymphomas, 2 follicular lymphomas, 4 CLL/small lymphocytic lymphomas (CLL/SLLs), and 1 low-grade NHL not otherwise specified. Thirty-nine patients received a sofosbuvir-based regimen and 7 patients received other DAAs. The median duration of DAA therapy was 12 weeks (range, 6-24 weeks). A sustained virological response at week 12 after finishing DAAs was obtained in 45 patients (98%); the overall LDR rate was 67%, including 12 patients (26%) who achieved a complete response. The LDR rate was 73% among patients with MZL, whereas no response was observed in CLL/SLL patients. Seven patients cleared cryoglobulins out of 15 who were initially positive. After a median follow-up of 8 months, 1-year progression-free and overall survival rates were 75% (95% confidence interval [CI], 51-88] and 98% [95% CI, 86-100], respectively. DAA therapy induces a high LDR rate in HCV-associated indolent lymphomas. These data provide a strong rationale for prospective trials with DAAs in this setting.

Acute hepatitis C: a 24-week course of pegylated interferon α-2b versus a 12-week course of pegylated interferon α-2b alone or with ribavirin.

UNLABELLED: Therapy of acute hepatitis C (AHC) has not yet been standardized and several issues are still unresolved. This open, randomized, multicenter trial aimed to assess the efficacy and safety of a 24-week course of pegylated IFN (Peg-IFN) alpha-2b versus a 12-week course of Peg-IFN alpha-2b alone or with ribavirin (RBV) in AHC patients. One hundred and thirty HCV acutely infected patients who did not spontaneously resolve by week 12 after onset were consecutively enrolled and randomized to receive Peg-IFN alpha-2b monotherapy (1.5 µg/kg/week) for 24 or 12 weeks (arm 1, n = 44 and arm 2, n = 43, respectively) or in combination with RBV (10.6 mg/kg/day) for 12 weeks (arm 3, n = 43). The primary endpoint was undetectable HCV RNA at 6-month posttreatment follow-up (sustained virological response; SVR). All patients were followed for 48 weeks after therapy cessation. HCV RNA levels were determined by real-time polymerase chain reaction (limit of detection: 15 IU/mL) at the central laboratory at baseline, week 4, end of treatment, and 6 and 12 months posttreatment. Using an intent-to-treat analysis, overall SVR rate was 71.5%. In particular, an SVR was achieved in 31 of 44 (70.5%), 31 of 43 (72.1%), and 31 of 43 (72.1%) patients in arms 1, 2, and 3, respectively (P = 0.898). Sixteen patients (12.3%) prematurely discontinued therapy or were lost to follow-up; thus, sustained response rates with per-protocol analysis were 81.6%, 81.6%, and 81.6% for patients in arms 1, 2, and 3 respectively. With multivariate analysis, virologic response at week 4 of treatment was an independent predictor of SVR. Peg-IFN alpha-2b was well tolerated. CONCLUSION: Peg-IFN alpha-2b induces a high SVR in chronically evolving AHC patients. Response rates were not influenced by combination therapy or treatment duration.

Snail1 transcription factor is a critical mediator of hepatic stellate cell activation following hepatic injury.

Following liver injury, the wound-healing process is characterized by hepatic stellate cell (HSC) activation from the quiescent fat-storing phenotype to a highly proliferative myofibroblast-like phenotype. Snail1 is a transcription factor best known for its ability to trigger epithelial-mesenchymal transition, to influence mesoderm formation during embryonic development, and to favor cell survival. In this study, we evaluated the expression of Snail1 in experimental and human liver fibrosis and analyzed its role in the HSC transdifferentiation process. Liver samples from patients with liver fibrosis and from mice treated by either carbon tetrachloride (CCl(4)) or thioacetamide (TAA) were evaluated for mRNA expression of Snail1. The transcription factor expression was investigated by immunostaining and real-time quantitative RT-PCR (qRT-PCR) on in vitro and in vivo activated murine HSC. Snail1 knockdown studies on cultured HSC and on CCl(4)-treated mice were performed by adenoviral delivery of short-hairpin RNA; activation-related genes were quantitated by real-time qRT-PCR and Western blotting. Snail1 mRNA expression resulted upregulated in murine experimental models of liver injury and in human hepatic fibrosis. In vitro studies showed that Snail1 is expressed by HSC and that its transcription is augmented in in vitro and in vivo activated HSC compared with quiescent HSC. At the protein level, we could observe the nuclear translocation of Snail1 in activated HSC. Snail1 knockdown resulted in the downregulation of activation-related genes both in vitro and in vivo. Our data support a role for Snail1 transcription factor in the hepatic wound-healing response and its involvement in the HSC transdifferentiation process.

Full-length characterization of hepatitis C virus subtype 3a reveals novel hypervariable regions under positive selection during acute infection.

Hepatitis C virus subtype 3a is a highly prevalent and globally distributed strain that is often associated with infection via injection drug use. This subtype exhibits particular phenotypic characteristics. In spite of this, detailed genetic analysis of this subtype has rarely been performed. We performed full-length viral sequence analysis in 18 patients with chronic HCV subtype 3a infection and assessed genomic viral variability in comparison to other HCV subtypes. Two novel regions of intragenotypic hypervariability within the envelope protein E2, of HCV genotype 3a, were identified. We named these regions HVR495 and HVR575. They consisted of flanking conserved hydrophobic amino acids and central variable residues. A 5-amino-acid insertion found only in genotype 3a and a putative glycosylation site is contained within HVR575. Evolutionary analysis of E2 showed that positively selected sites within genotype 3a infection were largely restricted to HVR1, HVR495, and HVR575. Further analysis of clonal viral populations within single hosts showed that viral variation within HVR495 and HVR575 were subject to intrahost positive selecting forces. Longitudinal analysis of four patients with acute HCV subtype 3a infection sampled at multiple time points showed that positively selected mutations within HVR495 and HVR575 arose early during primary infection. HVR495 and HVR575 were not present in HCV subtypes 1a, 1b, 2a, or 6a. Some variability that was not subject to positive selection was present in subtype 4a HVR575. Further defining the functional significance of these regions may have important implications for genotype 3a E2 virus-receptor interactions and for vaccine studies that aim to induce cross-reactive anti-E2 antibodies.

Insulin resistance predicts rapid virological response in non-diabetic, non-cirrhotic genotype 1 HCV patients treated with peginterferon alpha-2b plus ribavirin.

BACKGROUND/AIMS: The rapid decline in hepatitis C virus RNA is crucial for determining the outcome of therapy in patients with genotype 1 chronic hepatitis C. However, the variables influencing the early phase of viral decay are still largely unexplored. We aimed to assess which pre-treatment variable may predict rapid virologic response (RVR) and sustained virologic response (SVR). METHODS: We evaluated 90 consecutive non-diabetic patients with genotype 1 chronic hepatitis C without cirrhosis, treated with peginterferon alpha-2b plus ribavirin. Viral load (COBAS Amplicore, Roche) was measured at 1, 4 and 12 weeks after starting treatment, and then 24 weeks after the end of treatment. RESULTS: The overall SVR was 47%. The SVR in patients with RVR was 100%. Age, GGT levels, viral load, steatosis, fibrosis and HOMA-IR were significantly associated with RVR in univariate analysis. After logistic regression, HOMA-IR proved to be the strongest independent predictor of RVR (OR 0.37, 95% CI: 0.16-0.89; p=0.027), whereas fibrosis had a weaker independent association with RVR (OR 0.32, 95% CI: 0.1-1.04; p=0.057). Among the eight pre-treatment variables, both BMI and steatosis were significantly associated with HOMA-IR, either in univariate or in multivariate analyses. CONCLUSIONS: Our data suggest that insulin resistance is strongly associated with RVR, thus reflecting the important role played by metabolic factors in the early phase of viral kinetics. HOMA-IR would appear to be a useful tool in predicting RVR and should be evaluated at baseline in all chronic hepatitis C patients before initiating antiviral treatment.

Antiviral activity of bone morphogenetic proteins and activins.

Understanding the control of viral infections is of broad importance. Chronic hepatitis C virus (HCV) infection causes decreased expression of the iron hormone hepcidin, which is regulated by hepatic bone morphogenetic protein (BMP)/SMAD signalling. We found that HCV infection and the BMP/SMAD pathway are mutually antagonistic. HCV blunted induction of hepcidin expression by BMP6, probably via tumour necrosis factor (TNF)-mediated downregulation of the BMP co-receptor haemojuvelin. In HCV-infected patients, disruption of the BMP6/hepcidin axis and genetic variation associated with the BMP/SMAD pathway predicted the outcome of infection, suggesting that BMP/SMAD activity influences antiviral immunity. Correspondingly, BMP6 regulated a gene repertoire reminiscent of type I interferon (IFN) signalling, including upregulating interferon regulatory factors (IRFs) and downregulating an inhibitor of IFN signalling, USP18. Moreover, in BMP-stimulated cells, SMAD1 occupied loci across the genome, similar to those bound by IRF1 in IFN-stimulated cells. Functionally, BMP6 enhanced the transcriptional and antiviral response to IFN, but BMP6 and related activin proteins also potently blocked HCV replication independently of IFN. Furthermore, BMP6 and activin A suppressed growth of HBV in cell culture, and activin A inhibited Zika virus replication alone and in combination with IFN. The data establish an unappreciated important role for BMPs and activins in cellular antiviral immunity, which acts independently of, and modulates, IFN.

Corrigendum: Conformational rearrangements in the transmembrane domain of CNGA1 channels revealed by single-molecule force spectroscopy.

This corrects the article DOI: 10.1038/ncomms8093.

Acute hepatitis E virus infection in a migrant population in North East Italy: A retrospective analysis.

OBJECTIVE: To study the epidemiological and clinical features of Hepatitis E Virus (HEV) infection in a migrant population. METHODS: We performed a retrospective chart review, identifying a cohort of 21 symptomatic patients of migrant origin with confirmed HEV infection admitted in the period between January 1995-November 2014. RESULTS: 20 (95%) patients came from South Asian countries highly endemic for HEV, all positive for HEV genotype 1. Recent travel to a highly endemic country was the most consistent risk factor identified in 90% of cases, duration from return to Italy to hospitalization ranged from 10 to 120 days. Nausea and vomiting (100%), jaundice (95.2%), and anorexia (85.7%) were the most common reported symptoms. Fever was present in 57.1% of cases. Transaminase values were elevated in all patients and serum bilirubin was raised in 86% of patients. We found no statistically significant differences between clinical symptoms, laboratory results or duration of hospitalization in patients with co-morbidities compared to those without. We also report a secondary case of HEV genotype 1 transmitted within Italy. CONCLUSION: Our study highlights the epidemiological risk factors and clinical features of HEV infection in a migrant population in Italy and should stimulate further research regarding the prevalence and morbidity of HEV within migrant populations in Europe.

Onset of type 1 diabetes mellitus during peginterferon alpha-2b plus ribavirin treatment for chronic hepatitis C.

A 61-year-old man was observed to develop type 1 diabetes mellitus following a 3-month treatment with recombinant alpha-2b peginterferon combined with ribavirin for chronic hepatitis C. Serum samples, collected before the start of therapy and 2 months after the diagnosis of diabetes mellitus, revealed islet-cell antibodies at a titer of 20 and 40 JDF-U, respectively, and glutamic acid decarboxylase autoantibodies at a value of 76.5 and 196 IU/ml, respectively. Antibodies to second islet autoantigen were persistently negative. HLA class II typing revealed the presence of DRB1*04/DRB1*14, DQA1*0303-0104 and DQB1*04-0503 alleles. Eight months after the onset of type 1 diabetes mellitus, the patient is still receiving 30 IU insulin daily; the liver function tests are normal and serum hepatitis C virus RNA is negative. These data confirm that, in patients with potential diabetes mellitus, the disease may become manifest as a side-effect during therapy with peginterferon-alpha plus ribavirin. The patient as a candidate for interferon treatment should therefore be investigated, in addition to thyroid autoimmunity, also for pancreatic autoantibodies before starting therapy.

The Role of Rac1 in the Growth Cone Dynamics and Force Generation of DRG Neurons.

We used optical tweezers, video imaging, immunocytochemistry and a variety of inhibitors to analyze the role of Rac1 in the motility and force generation of lamellipodia and filopodia from developing growth cones of isolated Dorsal Root Ganglia neurons. When the activity of Rac1 was inhibited by the drug EHop-016, the period of lamellipodia protrusion/retraction cycles increased and the lamellipodia retrograde flow rate decreased; moreover, the axial force exerted by lamellipodia was reduced dramatically. Inhibition of Arp2/3 by a moderate amount of the drug CK-548 caused a transient retraction of lamellipodia followed by a complete recovery of their usual motility. This recovery was abolished by the concomitant inhibition of Rac1. The filopodia length increased upon inhibition of both Rac1 and Arp2/3, but the speed of filopodia protrusion increased when Rac1 was inhibited and decreased instead when Arp2/3 was inhibited. These results suggest that Rac1 acts as a switch that activates upon inhibition of Arp2/3. Rac1 also controls the filopodia dynamics necessary to explore the environment.

MAIT cells are activated during human viral infections.

Mucosal-associated invariant T (MAIT) cells are abundant in humans and recognize bacterial ligands. Here, we demonstrate that MAIT cells are also activated during human viral infections in vivo. MAIT cells activation was observed during infection with dengue virus, hepatitis C virus and influenza virus. This activation-driving cytokine release and Granzyme B upregulation-is TCR-independent but dependent on IL-18 in synergy with IL-12, IL-15 and/or interferon-α/ß. IL-18 levels and MAIT cell activation correlate with disease severity in acute dengue infection. Furthermore, HCV treatment with interferon-α leads to specific MAIT cell activation in vivo in parallel with an enhanced therapeutic response. Moreover, TCR-independent activation of MAIT cells leads to a reduction of HCV replication in vitro mediated by IFN-γ. Together these data demonstrate MAIT cells are activated following viral infections, and suggest a potential role in both host defence and immunopathology.

The role of myosin-II in force generation of DRG filopodia and lamellipodia.

Differentiating neurons process the mechanical stimulus by exerting the protrusive forces through lamellipodia and filopodia. We used optical tweezers, video imaging and immunocytochemistry to analyze the role of non-muscle myosin-II on the protrusive force exerted by lamellipodia and filopodia from developing growth cones (GCs) of isolated Dorsal Root Ganglia (DRG) neurons. When the activity of myosin-II was inhibited by 30 µM Blebbistatin protrusion/retraction cycles of lamellipodia slowed down and during retraction lamellipodia could not lift up axially as in control condition. Inhibition of actin polymerization with 25 nM Cytochalasin-D and of microtubule polymerization with 500 nM Nocodazole slowed down the protrusion/retraction cycles, but only Cytochalasin-D decreased lamellipodia axial motion. The force exerted by lamellipodia treated with Blebbistatin decreased by 50%, but, surprisingly, the force exerted by filopodia increased by 20-50%. The concomitant disruption of microtubules caused by Nocodazole abolished the increase of the force exerted by filopodia treated with Blebbistatin. These results suggest that; i- Myosin-II controls the force exerted by lamellipodia and filopodia; ii- contractions of the actomyosin complex formed by filaments of actin and myosin have an active role in ruffle formation; iii- myosin-II is an essential component of the structural stability of GCs architecture.

Conformational rearrangements in the transmembrane domain of CNGA1 channels revealed by single-molecule force spectroscopy.

Cyclic nucleotide-gated (CNG) channels are activated by binding of cyclic nucleotides. Although structural studies have identified the channel pore and selectivity filter, conformation changes associated with gating remain poorly understood. Here we combine single-molecule force spectroscopy (SMFS) with mutagenesis, bioinformatics and electrophysiology to study conformational changes associated with gating. By expressing functional channels with SMFS fingerprints in Xenopus laevis oocytes, we were able to investigate gating of CNGA1 in a physiological-like membrane. Force spectra determined that the S4 transmembrane domain is mechanically coupled to S5 in the closed state, but S3 in the open state. We also show there are multiple pathways for the unfolding of the transmembrane domains, probably caused by a different degree of α-helix folding. This approach demonstrates that CNG transmembrane domains have dynamic structure and establishes SMFS as a tool for probing conformational change in ion channels.

Occult hepatitis B virus infection does not affect liver histology or response to therapy with interferon alpha and ribavirin in intravenous drug users with chronic hepatitis C.

BACKGROUND: the frequency and the impact of occult HBV infection in patients with chronic hepatitis C infection is still a matter of some controversy. OBJECTIVES: our aim was to evaluate the prevalence of occult HBV infection and assess its impact on liver biochemistry, HCV viral titre, liver histology and on outcome of therapy in patients with chronic hepatitis C. STUDY DESIGN: paired liver biopsies and serum samples were collected from 51 patients (84% IVDUS) with HBsAg negative chronic hepatitis C, and tested for HBV-DNA with nested PCR. Liver biopsies were further studied histologically, with morphometric analyses and immunostaining techniques. Twenty-five were treated with alpha Interferon and ribavirin and followed for at least 18 months. RESULTS: HBV DNA was detected in 29.4% of liver tissue specimens and in only one (1.9%) serum sample. Three liver specimens were positive for surface gene, nine for core gene, three for both and none for the X gene. No significant difference in mean transaminase values, HCV viral titre, HCV genotype, or grading and staging and morphometric analysis was observed in patients with or without HBV DNA. Moreover, all 51 liver specimens were negative for both HBsAg and HBcAg. Sustained response to combination therapy was achieved in 40% of patients with and in 53% of patients without HBV DNA in the liver specimens (P=NS). CONCLUSIONS: HBV DNA is frequently found in the liver of patients with chronic hepatitis C. However, the lack of any significant impact on HCV viral titre, liver enzymes, histological parameters and response to therapy, suggests that in most cases HBV DNA detected in the liver by PCR may be either an integrated or low level replicative form.

Therapy of chronic hepatitis C with PEG-IFN α-2b plus ribavirin in patients with genotype 2 or 3: 16 versus 24 weeks, clinical outcome and direct cost analyses.

INTRODUCTION: Short antiviral therapy has been proposed for patients with chronic hepatitis C, easy genotypes, low fibrosis score, low viral load at baseline, and rapid virological response (RVR). However, this approach is not completely accepted. OBJECTIVES: The aims of this study were (a) to evaluate the sustained virological response (SVR) in noncirrhotic patients with genotype 2 or 3, achieving an RVR, randomized to receive pegylated-interferon (IFN) α-2b plus ribavirin for either 16 or 24 weeks and (b) to carry out direct cost analysis comparing patients treated for 16 versus 24 weeks. RESULTS: Of the 142 initially evaluated patients, 130 were enrolled according to the selection criteria, but independent of the viral load. According to the intention-to-treat analysis, SVR was achieved in 104 patients (80%). Logistic regression analysis showed that RVR (P<0.001) and genotype 2 (P<0.03) were the most important factors independently associated with SVR. Among patients with RVR, SVR was comparable between patients treated for 16 weeks and those treated for 24 weeks (86.2 vs. 89.7%, P=NS). The mean direct costs were €4003.7 for patients treated for 16 weeks and €5676.7 for those treated for 24 weeks, with a 30% difference between the two arms. CONCLUSION: In patients achieving an RVR, a 16-week treatment with pegylated-interferon plus ribavirin was comparable to a 24-week treatment. Short treatment in patients with RVR allows us to save 30% of the direct costs, independent of the viral load at baseline.

Changing epidemiology of HCV and HBV infections in Northern Italy: a survey in the general population.

AIM: To evaluate the hepatitis B virus (HBV) and the hepatitis C virus (HCV) epidemiology in the general population of Northern Italy, a cohort of 965 subjects, all residents (including 47 immigrants), were anonymously tested for HBV and HCV infections. MATERIAL AND METHODS: Serum samples were assayed for anti-HCV and anti-HBV markers by enzyme-linked immunosorbent assay and for HCV-RNA by polymerase chain reaction, and the positive cases were genotyped. HBsAg-positive cases were assayed for HBeAg/anti-HBe, whereas HBsAg negatives were tested for both anti-HBc and anti-HBs. RESULTS: The overall prevalence of anti-HCV was 2.6%, with a bimodal distribution characterized by the highest prevalence (12%) in subjects over 75 years old. None of the subjects under 25 years old was anti-HCV positive. Anti-HCV positivity was similar in males and females (2.4% vs. 2.7%). HCV-RNA was positive in 40% of cases and genotype 1 was the most common. The HBsAg prevalence was 1%, with a significant difference according to country of origin (0.8% in Italian subjects vs. 6.4% in immigrants, P=0.01). HBsAg positivity increased significantly with age (R2=0.57, P<0.02). The overall percentages for the prevalence of isolated anti-HBs, anti-HBs+/anti-HBc+, and isolated anti-HBc were 23.8%, 8.4%, and 4.2%, respectively. CONCLUSIONS: Our study provides a new picture of HCV and HBV epidemiology in Northern Italy, with these features: (1) a cohort effect showing a reduction of HCV infection in the elderly, possible due to age-related mortality; (2) an unchanged overall prevalence of HBV infection, despite continuing immigration of subjects from endemic countries.

Impact of occult HBV infection in HIV/HCV co-infected patients: HBV-DNA detection in liver specimens and in serum samples.

Prevalence and impact of occult HBV infection in HIV positive patients is controversial. The aims of this study were to determine the prevalence of occult HBV infection and its impact on histological and virological parameters. 52 HIV/HCV (but HBsAg-negative) co-infected patients, 29 HBsAg and anti-HCV negative chronic hepatitis, and 20 HBsAg positive chronic hepatitis controls were studied. DNA was extracted from frozen biopsies and amplified with primers for S, C and X regions, and for (ccc) HBV-DNA. Sera were tested for HBV-DNA with two quantitative assays (Cobas Amplicor HBV Monitor, and the real-time COBAS (r) Taqman HBV Test, Roche Diagnostics, UK). Occult HBV infection was detected in 7 (13.4%) liver biopsies of the study group, and in none case of the non viral chronic hepatitis group (p=0.04). All serum samples were HBV-DNA negative with Cobas Amplicor HBV monitor assay, while 3 cases were found positive with real time PCR. Statistical analysis didn't show any impact of occult HBV infection on liver histology, CD4+ cells count, HIV and HCV load, and ALT levels. Occult B infection is relatively frequent in HIV/HCV co-infected patients, and is underestimated by common HBV-DNA serological assays. However, it doesn't seem to exert a relevant impact.