Addition of PEG-interferon to long-term nucleos(t)ide analogue therapy enhances HBsAg decline and clearance in HBeAg-negative chronic hepatitis B: Multicentre Randomized Trial (PAS Study)

We studied whether 48 weeks of PEG-IFN alfa-2a add-on increases HBsAg-decline and clearance in HBeAg-negative patients on long-term nucleo(s)tide analogue (NA) therapy. In this investigator-initiated, randomized, controlled trial conducted in Europe and Canada, HBeAg-negative patients treated with NA > 12 months, with HBVDNA < 200 IU/mL, were enrolled. Patients were randomized 2:1 to 48 weeks of PEG-IFN alfa-2a add-on (180 μg per week) or continued NA-monotherapy with subsequent follow-up to Week 72. Endpoints were HBsAg decline (≥1 log10 IU/mL) and HBsAg clearance at Week 48. Of the 86 patients in the modified-intention-to-treat analysis, 58 patients received PEG-IFN add-on, and 28 continued NA monotherapy. At Week 48, 16(28%) patients achieved HBsAg decline ≥1 log10 in the add-on arm versus none on NA-monotherapy (p < .001), and HBsAg clearance was observed in 6 (10%) PEG-IFN add-on patients versus 0% NA-monotherapy (p = .01). HBVRNA was only detected in 2% after PEG-IFN treatment versus 19% in NA-monotherapy (p = .002) at Week 48. PEG-IFN add-on therapy was well tolerated in majority of patients. Low baseline HBsAg levels (<10 IU/mL) identified patients most likely to achieve HBsAg loss with PEG-IFN add-on, whereas an HBsAg level > 200 IU/mL at on-treatment Week 12 was highly predictive of non-response (NPV = 100%). Addition of PEG-IFN to long-term NA enhanced HBsAg decline and increased the chance of HBsAg clearance in HBeAg-negative patients on long-term NA. On-treatment HBsAg levels >200 IU/mL identify patients unlikely to benefit from PEG-IFN add-on and could be used as a potential stopping-rule for PEG-IFN therapy. Our findings support further exploration of immune modulation add-on to antiviral therapy, preferably using response-guided strategies, to increase functional cure rates in patients with CHB.

HBV transcription and translation persist despite viral suppression in HBV-HIV co-infected patients on antiretroviral therapy

BACKGROUND AND AIMS

Liver injury may persist in patients with HBV receiving antiviral therapy who have ongoing transcription and translation. We sought to assess ongoing HBV transcription by serum HBV RNA, translation by serum hepatitis B core related antigen (HBcrAg), and their associations with hepatic HBsAg and HBcAg staining in patients coinfected with HBV and HIV.

METHODS

This is a cross-sectional study of 110 adults coinfected with HBV and HIV who underwent clinical assessment and liver biopsy. Immunohistochemistry (IHC) was performed for HBsAg and HBcAg. Viral biomarkers included quantitative HBsAg, HBV RNA, and HBcrAg.

RESULTS

Participants' median age was 49 years (male, 93%; Black, 51%; HBeAg+, 65%), with suppressed HBV DNA (79%) and undetectable HIV RNA (77%) on dually active antiretroviral therapy. Overall, HBV RNA and HBcrAg were quantifiable in 81% and 83%, respectively (96% and 100% in HBeAg+, respectively). HBcAg staining was detected in 60% and HBsAg in 79%. Higher HBV RNA was associated with higher HBcAg and HBsAg IHC grades (both p < 0.0001). The HBsAg membranous staining pattern was significantly associated with higher HBV-RNA and HBcrAg levels.

CONCLUSION

HBcAg and HBsAg IHC staining persisted despite viral suppression, and IHC grades and staining patterns correlated with markers of transcription (HBV RNA) and translation (HBcrAg). These data indicate that apparent HBV suppression is associated with residual transcription and translation that could contribute to liver pathology. Additional antiviral strategies directed to HBV protein expression may be useful to ameliorate liver injury.

A prospective cohort study of renal function and bone turnover in adults with hepatitis B virus (HBV)-HIV co-infection with high prevalence of tenofovir-based antiretroviral therapy use

OBJECTIVE

Tenofovir disoproxil fumarate (TDF) is a common component of antiretroviral therapy in hepatitis B virus (HBV)-HIV co-infected adults but few studies have evaluated worsening renal function and bone turnover, known effects of TDF.

METHODS

Adults from eight North American sites were enrolled in this cohort study. Research assessments were conducted at entry and every 24 weeks for ≤192 weeks. Bone markers were tested at baseline, week 96 and week 192 from stored serum. We evaluated changes in markers of renal function and bone turnover over time and potential contributing factors.

RESULTS

A total of 115 patients were prospectively followed; median age 49 years, 91% male and 52% non-Hispanic Black. Duration of HIV was 20.5 years. TDF use ranged from 80% to 92% throughout follow-up. Estimated glomerular filtration rate (eGFR) (ml/min/1.73m² ) decreased from 87.1 to 79.9 over 192 weeks (p < 0.001); however, the prevalence of eGFR <60 ml/min/1.73m² did not appear to differ over time (always <16%; p = 0.43). From baseline to week 192, procollagen type I N-terminal propeptide (P1NP) (146.7 to 130.5 ng/ml; p = 0.001), osteocalcin (14.4 to 10.2 ng/ml; p < 0.001) and C-terminal telopeptides of type I collagen (CTX-1) (373 to 273 pg/ml; p < 0.001) decreased. Younger age, male sex and overweight/obesity versus normal weight predicted a decrease in eGRF. Black race, healthy weight versus underweight, advanced fibrosis, undetectable HBV DNA, and lower parathyroid hormone level predicted worsening bone turnover.

CONCLUSION

In this HBV-HIV cohort with high prevalence of TDF use, several biomarkers of renal function and bone turnover indicated worsening status over approximately 4 years, highlighting the importance of clinical awareness in co-infected adults.

A Prospective Cohort Study of Novel Markers of Hepatitis B Virus Replication in Human Immunodeficiency Virus Coinfection

BACKGROUND & AIMS

The contribution of the novel biomarkers, hepatitis B virus (HBV) RNA and HBV core-related antigen (HBcrAg), to characterization of HBV-human immunodeficiency virus (HIV) coinfection is unclear. We evaluated the longitudinal dynamics of HBV RNA and HBcrAg and their association with classical HBV serum biomarkers and liver histology and viral staining.

METHODS

HBV-HIV co-infected adults from 8 North American centers entered a National Institutes of Health-funded prospective cohort study. Demographic, clinical, serological, and virological data were collected at entry and every 24 to 48 weeks for up to 192 weeks. Participants with HBV RNA and HBcrAg measured ≥2 times (N = 95) were evaluated; 56 had paired liver biopsies obtained at study entry and end of follow-up.

RESULTS

Participants had a median age of 50 years; 97% were on combination anti-viral therapy. In hepatitis B e antigen (HBeAg)+ participants, there were significant declines in HBV RNA and HBcrAg over 192 weeks that tracked with declines in HBeAg, hepatitis B surface antigen, HBV DNA, and hepatitis B core antigen (HBcAg) hepatocyte staining grade (all P < .05). In HBeAg- participants, there were not significant declines in HBV RNA (P = .49) and HBcrAg (P = .63), despite modest reductions in hepatitis B surface antigen (P < .01) and HBV DNA (P = .03). HBV serum biomarkers were not significantly related to change in hepatic activity index, Ishak fibrosis score, or hepatocyte HBcAg loss (all P > .05).

CONCLUSIONS

In HBV-HIV coinfected adults on suppressive dually active antiviral therapy, the use of novel HBV markers reveals continued improvement in suppression of HBV transcription and translation over time. The lack of further improvement in HBV serum biomarkers among HBeAg- patients suggests limits to the benefit of combination anti-viral therapy and provide rationale for additional agents with distinct mechanisms of action.

Early virologic relapse predicts alanine aminotransferase flares after nucleos(t)ide analogue withdrawal in patients with chronic hepatitis B

When patients with chronic hepatitis B (CHB) stop nucleos(t)ide analogue (NA) therapy before achieving HBsAg loss, flares often ensue which are challenging to predict early. We determined the incidence, severity, outcome and predictors of flares after NA withdrawal. Forty-five patients enrolled in an RCT were included; 107 patients from an external, prospective cohort were used for validation. Retreatment criteria were pre-defined. Pre- and post-treatment predictors of alanine aminotransferase (ALT) flare (>5× ULN) were evaluated by Cox proportional-hazards regression. Seventy-two weeks after NA withdrawal, 23/45 (51%) patients had developed >5× ULN and 14 (31%) >20× ULN. Median time to develop ALT >5× ULN was 12 weeks after NA withdrawal. Independent predictors of ALT >5× ULN were male sex (HR [95% CI] 3.2 [1.2-8.9]; p = 0.03) and serum HBV DNA (1.2 [1.0-1.8]; p = 0.03) at Week 6 off-therapy. Specifically, week 6 HBV DNA >10,000 IU/ml predicted ALT >5× ULN (3.4 [1.4-8.4]; p = 0.01), which was externally validated. In conclusion, this study on post-treatment flares revealed a high cumulative incidence in CHB. Week 6 HBV DNA >10,000 IU/ml independently predicted flares. The proposed threshold enables prediction of imminent flares in patients who may benefit from closer monitoring and earlier retreatment.

SARS-CoV-2 Infections Among Patients With Liver Disease and Liver Transplantation Who Received COVID-19 Vaccination

Many safe and effective severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccinations dramatically reduce risks of coronavirus disease 2019 (COVID-19) complications and deaths. We aimed to describe cases of SARS-CoV-2 infection among patients with chronic liver disease (CLD) and liver transplant (LT) recipients with at least one prior COVID-19 vaccine dose. The SECURE-Liver and COVID-Hep international reporting registries were used to identify laboratory-confirmed COVID-19 in CLD and LT patients who received a COVID-19 vaccination. Of the 342 cases of lab-confirmed SARS-CoV-2 infections in the era after vaccine licensing, 40 patients (21 with CLD and 19 with LT) had at least one prior COVID-19 vaccination, including 12 who were fully vaccinated (≥2 weeks after second dose). Of the 21 patients with CLD (90% with cirrhosis), 7 (33%) were hospitalized, 1 (5%) was admitted to the intensive care unit (ICU), and 0 died. In the LT cohort (n = 19), there were 6 hospitalizations (32%), including 3 (16%) resulting in mechanical ventilation and 2 (11%) resulting in death. All three cases of severe COVID-19 occurred in patients who had a single vaccine dose within the last 1-2 weeks. In contemporary patients with CLD, rates of symptomatic infection, hospitalization, ICU admission, invasive ventilation, and death were numerically higher in unvaccinated individuals. Conclusion: This case series demonstrates the potential for COVID-19 infections among patients with CLD and LT recipients who had received the COVID-19 vaccination. Vaccination against SARS-CoV-2 appears to result in favorable outcomes as attested by the absence of mechanical ventilation, ICU, or death among fully vaccinated patients.

Performance of Serum-Based Scores for Identification of Mild Hepatic Steatosis in HBV Mono-infected and HBV-HIV Co-infected Adults

BACKGROUND

There are limited data on noninvasive methods to identify hepatic steatosis in coexisting hepatitis B virus (HBV) infection.

AIMS

To evaluate the diagnostic performance of noninvasive serum-based scores to detect steatosis using two distinct chronic HBV cohorts with liver histology evaluation.

METHODS

Chronic HBV cohorts with untreated HBV mono-infection (N = 302) and with treated HBV-HIV (N = 92) were included. Liver histology was scored centrally. Four serum-based scores were calculated: hepatic steatosis index (HSI), nonalcoholic fatty liver disease Liver Fat Score (NAFLD-LFS), visceral adiposity index (VAI), and triglyceride glucose (TyG) index. Optimal cutoffs (highest sensitivity + specificity) to detect ≥ 5% HS, stratified by cohort, were evaluated.

RESULTS

HBV-HIV (vs. HBV mono-infected) patients were older (median 50 vs. 43 years), and a higher proportion were male (92% vs. 60%), were black (51% vs. 8%), had the metabolic syndrome (41% vs. 25%), and suppressed HBV DNA (< 1000 IU/mL; 82% vs. 9%). Applying optimal cutoffs, the area under the receiver operator curve for detecting ≥ 5% steatosis in HBV-only and HBV-HIV, respectively, was 0.69 and 0.61 for HSI, 0.70 and 0.76 for NAFLD-LFS, 0.68 and 0.64 for TyG, and 0.68 and 0.69 for VAI. The accuracy of optimal cutoffs ranged from 61% (NAFLD-LFS) to 67% (TyG) among HBV-only and 56% (HSI) to 76% (NAFLD-LFS) among HBV-HIV. Negative predictive values were higher than positive predictive values for all scores in both groups.

CONCLUSION

The relative utility of scores to identify steatosis in chronic HBV differs by co-infection/anti-HBV medication status. However, even with population-specific cutoffs, several common serum-based scores have only moderate utility. ClinicalTrials.gov NCT01924455.

Fatty Liver Disease in a Prospective North American Cohort of Adults With Human Immunodeficiency Virus and Hepatitis B Virus Coinfection

BACKGROUND

Hepatitis B virus (HBV) and fatty liver disease (FLD) are common in human immunodeficiency virus (HIV). Correlates of FLD and its relationship with alanine aminotransferase (ALT) were examined longitudinally in HIV-HBV coinfection.

METHODS

From 28/4/2014-7/11/2018, 114 HIV-HBV adults had liver biopsy and were followed for a median of 3 years (ancillary study of Hepatitis B Research Network). Steatohepatitis was based on presence of steatosis, ballooning, and perisinusoidal fibrosis. FLD was defined as ≥5% steatosis and/or steatohepatitis.

RESULTS

Median age was 49 years, 93% were male, 51% black, 93% had HIV RNA <400 copies/mL and 83% HBV DNA <1000 IU/mL. Thirty percent had FLD (20% steatosis, 10% steatohepatitis). Those with FLD had higher median triglyceride (171 vs 100 mg/dL, P < .01) and small, dense LDL (44 vs 29 mg/dL, P < .01) and lower HDL-2-C (9 vs 12 mg/dL, P = .001). After adjusting for age, sex, and alcohol use, white and other versus black race (ORs, 8.49 and 16.54, respectively), ALT (OR, 3.13/doubling), hypertension (OR, 10.93), hyperlipidemia (OR, 4.36), and diabetes family history (OR, 5.38) were associated with having FLD (all P < .05). Steatohepatitis or steatosis alone (vs none) was associated with higher ALT over time (1.93 and 1.34 times higher, respectively; P < .001), with adjustment for age, sex, and HBV DNA.

CONCLUSIONS

About 30% with HIV-HBV coinfection had FLD including 10% with steatohepatitis. FLD was associated with non-black race, metabolic risks, an atherogenic lipid profile, and elevated ALT over time. Thus, identification of FLD and management of adverse metabolic profiles are critically important in HIV-HBV coinfection. Clinical Trial Registration. NCT01924455.

A Prospective Study Evaluating Changes in Histology, Clinical and Virologic Outcomes in HBV-HIV Co-infected Adults in North America

BACKGROUND AND AIMS

Histological and clinical outcomes in HBV-HIV coinfection in the era of combination antiretroviral therapy (cART) are poorly defined.

APPROACH AND RESULTS

Adult patients co-infected with HBV-HIV from eight North American sites were enrolled in this National Institutes of Health (NIH)-funded prospective observational study (n = 139). Demographic, clinical, serological, and virological data were collected at entry and every 24 weeks for ≤ 192 weeks. Paired liver biopsies were obtained at study entry and at ≥ 3 years of follow-up. Biopsies were assessed by a central pathology committee using the modified Ishak scoring system. Clinical outcome rate and changes in histology are reported. Among participants with follow-up data (n = 114), median age was 49 years, 91% were male, 51% were non-Hispanic Black, and 13% had at-risk alcohol use, with a median infection of 20 years. At entry, 95% were on anti-HBV cART. Median CD4 count was 562 cells/mm³ and 93% had HIV < 400 copies/mL. HBeAg was positive in 61%, and HBV DNA was below the limit of quantification (< 20 IU/mL) in 61% and < 1,000 IU/mL in 80%. Clinical events were uncommon across follow-up: one hepatic decompensation, two HCC, no liver transplants, and one HBV-related deaths, with a composite endpoint rate of 0.61/100 person-years. Incident cirrhosis (n = 1), alanine aminotransferase flare (n = 2), and HBeAg loss (n = 13) rates were 0.40, 0.65, and 6.86 per 100 person-years, respectively. No participants had HBsAg loss. Paired biopsy (n = 62; median 3.6 years apart) revealed minimal improvement in Histologic Activity Index (median [interquartile range]: 3 [2-4] to 3 [1-3]; P = 0.02) and no significant change in fibrosis score (1 [1-2] to 1 [0-3]; P = 0.58).

CONCLUSIONS

In a North American cohort of adults with HBV-HIV on cART with virological suppression, clinical outcomes and worsening histological disease were uncommon.

The Inflammatory Cytokine Profile Associated with Liver Damage is Broader and Stronger in Chronic Hepatitis B Patients Compared to Acute Hepatitis B Patients

Liver damage in hepatitis B is immune driven and correlates with inflammatory markers in patient serum. There is no comparison of these markers to determine if inflammatory profiles are distinct to different types of liver damage across patients at different stages of disease. We measured 25 inflammatory markers in acute hepatitis B, chronic hepatitis B patients with HBeAg seroconversion and chronic patients stopping nucleoside analogue therapy. Myeloid markers dominated the inflammatory profile in all stages of hepatitis B. More inflammatory markers were detectable in chronic patients, including elevated concentrations of cytotoxic effectors Fas ligand, TRAIL and TNF-α.

Low Incidence of Adverse Outcomes in Adults With Chronic Hepatitis B Virus Infection in the Era of Antiviral Therapy

BACKGROUND AND AIMS

Outcomes of persons with chronic hepatitis B virus (HBV) infection in the era of antiviral therapy (AVT) are not well characterized. We determined the incidence and factors associated with clinical outcomes in a multiethnic, North American cohort of adults with chronic HBV infection, who were not on AVT at enrollment.

APPROACH AND RESULTS

Adults with chronic HBV infection, not receiving AVT, and without a history of decompensation, HCC, or liver transplantation (LT), were prospectively followed. Participants with known human immunodeficiency virus (HIV), hepatitis C virus, or hepatitis D virus (HDV) coinfection were excluded. During follow-up, treatment could be initiated per standard of care. Clinical outcomes included: incident cirrhosis, decompensation, HCC, OLT, and HBV-related death. Among 1,418 participants analyzed, 51.5% were women, median age was 41.1 years, 75% were Asian, 10% White, 13% Black, 24% HBeAg(+), and 1.5% cirrhosis at baseline. During the study, 274 started treatment, 83 had an alanine aminotransferase flare, 118 of 330 initially HBeAg(+) became HBeAg(-), and 90 of 1,329 became HBsAg(-). After 6,641 person-years follow-up, 8 participants (4 of 21 with baseline cirrhosis) had 12 clinical outcomes (2 decompensation, 5 HCC, 2 OLT, and 3 HBV-related deaths) and 19 of 1,397 had incident cirrhosis. Twenty-one of 26 participants had first outcome before treatment, none had become HBsAg(-), whereas 5/9 HBeAg(+) had become HBeAg(-) at time of first outcome. Cumulative percentage of clinical outcomes was 16% at year 4 in participants with baseline cirrhosis and 2% (including incident cirrhosis) at year 7 in those without.

CONCLUSIONS

Incidence of adverse outcomes was low in this closely monitored, large cohort of North American adults with predominantly inactive, chronic HBV without cirrhosis. Our data highlight the benefits of HBsAg loss and the importance of early diagnosis and treatment to prevent cirrhosis and other complications of chronic HBV infection.

Maintained virological suppression and renal function with reduced dose tenofovir disoproxil fumarate in renally impaired chronic hepatitis B patients

Tenofovir disoproxil fumarate (TDF) effectively suppresses viral replication in chronic hepatitis B (CHB), but occasionally leads to renal impairment. We evaluated the prevalence of viral and biochemical breakthrough and renal function kinetics in renally impaired patients with CHB on reduced and on full-dose TDF. This clinic-based longitudinal cohort study included patients receiving full and reduced dose TDF (due to eGFR [Cockcroft-Gault] <60 mL/min/1.73 m² ). Viral and biochemical breakthroughs were assessed 1 month after starting full and reduced TDF dose until the end-of-follow-up. Breakthroughs were studied in full and reduced dose TDF, and renal function (MDRD) longitudinally before and after dose reduction within patients starting on full-dose TDF. Of 750 patients on TDF, 78 (10%) had reduced dose and 672 (90%) full dose. At the time of dose reduction, 36 (46%) patients had chronic kidney disease stage G3B. A viral breakthrough occurred in one cirrhotic dialysis-dependent patient (dosed 300 mg weekly) which resolved without signs of decompensation, and in one patient on full dose which resolved spontaneously. One biochemical breakthrough occurred during dose reduction and resolved naturally without viral breakthrough. The MDRD improved within the first year of dose reduction (+3.0 [2.5] mL/min per year; P < .005) and remained stable thereafter. Fifty-three (79%) patients reached an MDRD >50 mL/min during dose reduction. Low dose TDF maintains renal function and viral suppression in most renally impaired patients with CHB, even in those with advanced liver disease. This useful, yet simple strategy could be particularly viable in resource-constrained settings.

Evaluating Noninvasive Markers to Identify Advanced Fibrosis by Liver Biopsy in HBV/HIV Co-infected Adults

Noninvasive biomarkers are used increasingly to assess fibrosis in patients with chronic liver disease. We determined the utility of dual cutoffs for noninvasive biomarkers to exclude and confirm advanced fibrosis in hepatitis B virus (HBV)-human immunodeficiency virus (HIV) co-infected patients receiving combined antiretroviral therapy. Participants were anti-HIV/hepatitis B surface antigen-positive adults from eight clinical sites in the United States and Canada of the Hepatitis B Research Network. Fibrosis was staged by a central pathology committee using the Ishak fibrosis score (F). Clinical, laboratory, and vibration-controlled transient elastography (VCTE) data were collected at each site. Dual cutoffs for three noninvasive biomarkers (aspartate aminotransferase-to-platelet ratio index, Fibrosis-4 index [FIB-4], and liver stiffness by VCTE) with the best accuracy to exclude or confirm advanced fibrosis (F ≥ 3) were determined using established methodology. Of the 139 enrolled participants, 108 with a liver biopsy and having at least one noninvasive biomarker were included: 22% had advanced fibrosis and 54% had normal alanine aminotransferase. The median (interquartile range) of APRI (n = 106), FIB-4 (n = 106), and VCTE (n = 63) were 0.34 (0.26-0.56), 1.35 (0.99-1.89), and 4.9 (3.8-6.8) kPa, respectively. The area under the curve for advanced fibrosis was 0.69 for APRI, 0.66 for FIB-4, and 0.87 for VCTE. VCTE cutoffs of 5.0 kPa or less (to exclude) and 8.8 kPa or greater (to confirm) advanced fibrosis had a sensitivity of 92.3% and specificity of 96.0%, respectively, and accounted for 65.1% of participants. Among the 34.9% with values between the cutoffs, 26.1% had advanced fibrosis. Considering APRI or FIB-4 jointly with VCTE did not improve the discriminatory capacity. Conclusion: VCTE is a better biomarker of advanced fibrosis compared with APRI or FIB-4 in HBV/HIV co-infected adults on combined antiretroviral therapy. Using VCTE dual cutoffs, approximately two-thirds of patients could avoid biopsy to determine advanced fibrosis.

Limited sustained response after stopping nucleos(t)ide analogues in patients with chronic hepatitis B: results from a randomised controlled trial (Toronto STOP study)

OBJECTIVE

Although most patients with chronic hepatitis B (CHB) reach effective virological suppression with long-term nucleos(t)ide analogues (NA) therapy, some might not need to continue treatment for life. In this randomised, controlled, phase IV trial, we evaluated off-therapy outcomes in patients after discontinuing long-term NA therapy.

DESIGN

Patients who had received NA therapy for ≥1 year and achieved virological suppression (hepatitis B e antigen (HBeAg) seroconversion combined with undetectable hepatitis B virus (HBV) DNA ≥12 months in HBeAg-positive patients or undetectable HBV DNA ≥36 months in HBeAg-negative patients) were randomised 2:1 to stop or continue NA therapy for 72 weeks. Sustained disease remission (HBeAg negative, HBV DNA <2000 IU/mL and normal alanine aminotransferase (ALT)) was evaluated at 72 weeks after stopping NA therapy.

RESULTS

Among 67 enrolled patients, sustained disease remission was observed in 13/45 (29%) stop versus 18/22 (82%) continue patients. Hepatitis B surface antigen (HBsAg) loss occurred in two patients (one in each group). The median HBsAg decline from randomisation to week 72 was similar in both groups (0.2 (0.0-0.4) vs 0.1 (0.0-0.2) log IU/mL in stop vs continue patients). Among patients who stopped, 15/45 (33%) had virological or biochemical relapse and 17/45 (38%) were retreated according to predefined criteria. A total of 11/18 (61%) pretreatment HBeAg-positive versus 6/27 (22%) HBeAg-negative patients required retreatment (p=0.01). Fourteen (31%) patients developed ALT >10× upper limit of normal (ULN) and another 7 (16%) had ALT >5× ULN. No patients experienced liver decompensation or died.

CONCLUSION

The findings of this prospective study suggest limited benefit of stopping NA therapy in chronic hepatitis B.

TRIAL REGISTRATION NUMBER

NCT01911156.

1208. Preventing Transmission of Bloodborne Viruses from-Infected Healthcare Workers to Patients in Canadian Healthcare Settings: A National Guideline

Background

Infectious agents, such as bloodborne viruses (BBVs), can potentially be transmitted from healthcare workers (HCWs) to patients. In an effort to reduce this risk to patients, this guideline, which provides a framework for policies on the management of HCWs infected with BBVs in Canada, was developed.

Methods

A total of six systematic reviews (1995–2016) were conducted to inform the risk of transmission of human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV) from infected HCWs to patients and the infectivity of each virus related to source serum viral load. Three environmental scans were conducted to inform sections on disclosure of HCW’s serologic status, Expert Review Panels, and lookback investigations. Government partners and key stakeholder organizations were consulted and a Task Group provided technical expertise.

Results

The risk of HCW-to-patient BBV transmission is negligible, except during exposure-prone procedures where there is a risk of HCW injury and possible exposure of a patient’s open tissues to the HCW’s blood. Transmission rates were lowest with HIV and highest with HBV (Table 1). Rates varied with several factors including source viral load, nature of potential exposure, infection prevention and control breaches, susceptibility of exposed patient, and use of post-exposure prophylaxis where relevant. The extent of reporting bias for exposure incidents where transmission did not occur is unknown. Current antiviral therapy informed guideline recommendations, with viral load thresholds provided to assist treating physician, Expert Review Panels and regulatory authorities in determining a HCW’s fitness for practice.

Conclusion

Routine Practices (or Standard Precautions) are critical to prevent HCW-to-patient transmission of infections; including BBVs. Recommendations provided in this guideline aim to further reduce the already minimal risk of HCW-to-patient transmission. The guideline provides a pan-Canadian approach for managing HCWs infected with a BBV, with recommendations directly impacting clinical practice related to preventing and controlling healthcare-associated infections.

Disclosures

All authors: No reported disclosures.

Ten-year efficacy and safety of tenofovir disoproxil fumarate treatment for chronic hepatitis B virus infection

BACKGROUND & AIMS

Tenofovir disoproxil fumarate (TDF) is a first-line treatment for chronic hepatitis B (CHB). We aimed to describe the efficacy and safety profiles of TDF treatment for up to 10 years in a well-described cohort of CHB patients.

METHODS

Hepatitis B e antigen (HBeAg)-negative and HBeAg-positive patients from two randomised, double-blind trials (ClinicalTrials.gov: NCT00117676 and NCT00116805) completed 48 weeks of randomised treatment with TDF or adefovir dipivoxil. A subset of these patients was then eligible to receive open-label TDF treatment for up to 10 years. At Year 10, patients were assessed for virological suppression, alanine aminotransferase (ALT) normalisation, serological response, safety and tolerability.

RESULTS

Of 641 randomised and treated patients, 585 (91%) entered the open-label extension phase with 203 (32%) patients completing Year 10 of the study. At Year 10, 118/118 (100%) of HBeAg-negative patients and 78/80 (98%) of HBeAg-positive patients with available data achieved hepatitis B virus (HBV) DNA < 69 IU/mL, while 88/106 (83%) and 60/77 (78%) patients achieved ALT normalisation, respectively. Of the 23 patients with HBeAg status available at Year 10, 12 (52%) and six (27%) experienced HBeAg loss and seroconversion, respectively. No resistance to TDF was documented up to Year 10. In the period between Year 8 and Year 10, the safety profile of TDF was similar to previous reports, with few patients experiencing renal- or bone-related adverse events.

CONCLUSIONS

Over 10 years, TDF had a favourable safety profile, was well tolerated, and resulted in continued maintenance of virological suppression with no documented resistance.

Epidemiologic and clinical features of chronic hepatitis B virus infection in 8 Canadian provinces: a descriptive study by the Canadian HBV Network

BACKGROUND

Published Canadian epidemiologic data on hepatitis B virus (HBV) infection include single-centre studies or are focused on Indigenous populations. We performed a study to characterize the demographic and clinical features, liver disease status and treatment of people with chronic hepatitis B in Canada.

METHODS

In this descriptive, opportunistic, cross-sectional study, available data for people known to be monoinfected with HBV were collected by the Canadian HBV Network from existing clinical databases, with support from the National Microbiology Laboratory, Public Health Agency of Canada. Data were collected in all provinces with the exception of New Brunswick and Newfoundland and Labrador. We analyzed the data using parametric and nonparametric statistical methods, with a significance level of p < 0.05.

RESULTS

In the 9380 unique patient records reviewed, the median age was 48 years, and 5193 patients (55.4%) were male. Ethnicity information was available for 7858 patients, of whom 5803 (73.8%) were Asian, 916 (11.6%) were black and 914 (11.6%) were white. Most of those tested (5556/6796 [81.8%]) were negative for HBV e-antigen, and most of those with fibrosis data (3481/4260 [81.7%]) had minimal liver fibrosis, with more advanced fibrosis noted in older people (> 40 yr). Of the 980 patients with genotype data, 521 (53.2%) had genotype B or C infection. Most of the 9241 patients with known confirmed treatment status received tenofovir disoproxil fumarate (1655 [17.9%]), lamivudine (1434 [15.5%]) or entecavir (548 [5.9%]).

INTERPRETATION

Based on available data, Canadian patients with chronic hepatitis B are predominantly Asian and negative for HBV e-antigen, and have genotype B or C infection. Interprovincial variations were noted in antiviral treatment regimen. This multicentre nationwide study provides data regarding patients with chronic hepatitis B and may inform future studies on the epidemiologic features of HBV infection in Canada.

Preventing complications: Hepatitis B screening in cancer patients undergoing systemic therapy

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Background: Chemotherapy is a risk factor for HBV reactivation in pts with cancer and chronic HBV. Anti-viral prophylaxis can prevent reactivation but requires identification of infected pts. Many guidelines recommend universal HBV screening prior to cytotoxic/immunosuppressive-therapy, but lack of screening is common globally. A serious safety event and high prevalence of pts from HBV endemic regions receiving treatment at our institution led to a quality improvement project to increase HBV screening prior to chemotherapy. We aimed to increase HBV screening in pts starting systemic therapy at Princess Margaret by 100% by February 28, 2019. Methods: Starting April 2017, an interrupted time series study was undertaken. Baseline HBV screening rate was 43%. Diagnostics including interviews, process mapping and root cause analysis were performed. Interventions to address identified root causes were implemented including specifying required HBV tests, tips for ordering HBV tests, provision of electronic Hepatology referral form, a safety alert email, grand rounds presentation of serious safety event, including HBV screening rate in departmental monthly quality emails and Divisional meetings and adding positive HBV results to the laboratory alerting system. The main outcome measure was the proportion of pts starting systemic therapy screened for HBV. Process measures included correct test ordering, number of Hepatology referrals was a balancing measure. Results were analysed with statistical process control charts. Results: From April 2017-Feb 2019, 5604 pts commenced systemic therapy. Interventions were modified iteratively as the project progressed. HBV screening rate improved from 43 to 79% (84% improvement). Incidence of chronic HBV was routinely above the Canadian average ( > 2%). The percent of correctly ordered screening tests fell from 48 to 33% (31% worsening), while the volume of Hepatology referrals remained manageable (1.5 pts/week). Conclusions: Our Quality Improvement project led to a significant improvement in HBV screening prior to systemic therapy. Further interventions are planned to achieve our target improvement of 100%.

Prevalence and predictors of complementary and alternative medicine modalities in patients with chronic hepatitis B

BACKGROUND & AIMS

The use of complementary and alternative medicine (CAM) in patients with chronic hepatitis B (CHB) can interact with antiviral treatment or influence health-seeking behaviour. We aimed to study the use of individual CAM modalities in CHB and explore determinants of use, particularly migration-related, socio-economic and clinical factors.

METHODS

A total of 436 CHB outpatients who attended the Toronto Centre for Liver Disease in 2015-2016 were included in this cross-sectional study. Using the comprehensive I-CAM questionnaire and health records, data were collected on socio-demographic and clinical variables and on usage of 16 CAM modalities in the last year.

RESULTS

Sixty percent of patients were male, 74% were Asian and 46% were using antiviral treatment. Three-hundred and nine (71%) patients used CAM. Vitamin/mineral preparations (45% of patients) were most commonly used. Overall CAM use and the specific use of potentially injurious CAM, such as green tea extract (9.2%) and St. John's wort (0.2%), were not associated with liver disease severity. Female sex, family history of CHB, lower serum HBV DNA, and higher socio-economic status were independently associated with bio-holistic CAM use, the clinically most-relevant CAM group (P < 0.05); ethnicity, antiviral therapy use and liver disease severity were not.

CONCLUSIONS

CAM use among CHB patients was extensive, especially use of vitamin and mineral preparations, but without direct influence on liver disease severity. Bio-holistic CAM use appeared to be associated with socio-economic status rather than with ethnicity or liver disease severity. Despite the rare use of hepatotoxins, physicians should actively inquire about it.

Spectrum of Liver Disease in Hepatitis B Virus (HBV) Patients Co-infected with Human Immunodeficiency Virus (HIV): Results of the HBV-HIV Cohort Study

BACKGROUND

Because most HBV/HIV co-infected patients on combination antiretroviral therapy (cART) have suppressed HBV DNA and normal liver enzymes, the histologic spectrum of liver disease in HBV/HIV coinfection is poorly defined. To address this gap in knowledge, we conducted a prospective study to comprehensively characterize liver disease severity assessed by liver biopsy in a well-defined cohort of HBV/HIV patients in North America receiving cART.

METHODS

Adult HIV/HBsAg positive patients on stable cART were recruited. Demographic, clinical, serological, and virological data were collected. Liver histology was assessed by a central pathology committee. The association of demographic, clinical, serologic, and virologic characteristics with liver histology was assessed using logistic regression.

RESULTS

In this cross-sectional analysis, the mean age of the cohort (N = 139) was 49 years; 92% were male, 51% were non-Hispanic black, 7% had at-risk alcohol use with a median duration of infections of 14 years. The median ALT was 28 IU/L and CD4 count was 568 cells/mm. Almost all (99%) were on cART. Three-fourths (75%) had undetectable HIV RNA (<20 copies/mL). HBeAg was positive in 62%, HBV DNA was below the limit of quantification (<20 IU/mL) in 57% and <1000 IU/ mL in 80%; 7% had incomplete viral suppression (HBV DNA ≥1000 IU/mL and HIV RNA <20 copies/mL). Liver histology (available in n = 114) showed significant periportal, lobular, and portal inflammation (scores ≥2) in 14%, 31%, and 22% respectively. Over a third (37%) had significant fibrosis (Ishak stage ≥2); 24% had advanced fibrosis (Ishak stage ≥3). Higher ALT (adjusted OR 1.19 per 10 IU/L; 95% CI [1.01, 1.41]; p = 0.03) and lower platelet count (adjusted OR 0.81 per 20,000 mm; 95% CI [0.67-0.97]; p = 0.02) but not HBV DNA were independently associated with advanced fibrosis.

CONCLUSIONS

In this cohort of patients with HBV/HIV coinfection receiving long-term cART with viral suppression, we observed significant fibrosis in more than one-third of patients.

exRNA Atlas Analysis Reveals Distinct Extracellular RNA Cargo Types and Their Carriers Present across Human Biofluids

To develop a map of cell-cell communication mediated by extracellular RNA (exRNA), the NIH Extracellular RNA Communication Consortium created the exRNA Atlas resource (https://exrna-atlas.org). The Atlas version 4P1 hosts 5,309 exRNA-seq and exRNA qPCR profiles from 19 studies and a suite of analysis and visualization tools. To analyze variation between profiles, we apply computational deconvolution. The analysis leads to a model with six exRNA cargo types (CT1, CT2, CT3A, CT3B, CT3C, CT4), each detectable in multiple biofluids (serum, plasma, CSF, saliva, urine). Five of the cargo types associate with known vesicular and non-vesicular (lipoprotein and ribonucleoprotein) exRNA carriers. To validate utility of this model, we re-analyze an exercise response study by deconvolution to identify physiologically relevant response pathways that were not detected previously. To enable wide application of this model, as part of the exRNA Atlas resource, we provide tools for deconvolution and analysis of user-provided case-control studies.

Abstract 184: Hyperglycemia Enhances Pro-inflammatory Properties of Macrophage-derived Exosomes to Drive Hematopoiesis in Apolipoprotein E-deficient Mouse

Background and Purpose: Diabetes is recognized to enhance the frequency and severity of atherosclerosis and cardiovascular disease. Recent studies have shown that hyperglycemia is associated with enhanced hematopoiesis and macrophage accumulation in atherosclerotic lesions. We explored whether high glucose concentrations can enhance intercellular communication between mature macrophages and hematopoietic progenitors via exosomes to promote inflammation and diabetic atherosclerosis.

Methods: Bone marrow derived macrophages (BMDM) from C57BL/6 mice were cultured with normal (5mM) or high glucose concentrations (25mM). Exosomes were isolated with our cushioned-density gradient ultracentrifugation method followed by nanoparticle tracking and western blot analysis. Pro-inflammatory properties of high glucose exosomes (HGexo) were tested in vitro by exposing them to BMDM cultured in normal low glucose. The capacity for BMDM-derived exosomes to alter systemic and vascular inflammation were next tested by infusing 25-30 weeks-old ApoE -/- mice fed a chow diet with 3 x 10 10 exosomes three times a week, for four weeks.

Results: Our data show that HGexo can stimulate the expression of inflammatory cytokines (IL-6, IL-1ß) as well as NADPH oxidases (Nox-1 and Nox-4) in cultured BMDM. Furthermore, our findings show that intraperitoneally injected exosomes distribute to numerous organs and tissues including the bone marrow and the spleen. Lastly, HGexo enhance the expansion of multipotent and lineage committed hematopoietic progenitors.

Conclusions: We identify that exosomes derived from cultured BMDM exposed to high glucose have the capacity to exert intercellular communication in vitro , and in vivo. Our findings suggest that exosomes produced by macrophages exposed to hyperglycemia could represent an unsuspected source of inflammation to accelerate atherosclerosis in diabetes.

Faldaprevir, pegylated interferon, and ribavirin for treatment-naïve HCV genotype-1: pooled analysis of two phase 3 trials

INTRODUCTION & AIM

Faldaprevir is a potent once-daily (q.d.) hepatitis C virus (HCV) NS3/4A protease inhibitor. The STARTVerso1 and STARTVerso2 phase 3 studies evaluated faldaprevir plus peginterferon alfa-2a/ribavirin (PegIFN/RBV) in treatment-naïve patients with chronic HCV genotype-1 infection.

MATERIAL AND METHODS

Patients were randomized 1:2:2 to receive placebo, faldaprevir 120 mg q.d. (12 or 24 weeks) or faldaprevir 240 mg q.d. (12 weeks) all with PegIFN/RBV (24-48 weeks). Faldaprevir 120 mg for 12 weeks only (STARTVerso1 only) required early treatment success (ETS, HCV RNA < 25 IU/mL at week 4 and undetected at week 8). All faldaprevir-treated patients with ETS stopped PegIFN/RBV at week 24. Primary endpoint: sustained virologic response 12 weeks post-treatment (SVR12).

RESULTS

SVR12 rates were significantly higher for patients treated with faldaprevir 120 or 240 mg (72% and 73%, respectively) compared with placebo (50%); estimated differences (adjusted for trial, race, and genotype-1 subtype) faldaprevir 120 mg 24% (95% CI: 17-31%, P < 0.0001), faldaprevir 240 mg 23% (95% CI: 16-30%, P < 0.0001). Subgroup analyses consistently showed higher SVR12 rates for patients receiving faldaprevir compared with placebo. The incidence of adverse events (AEs) was similar in faldaprevir 120-mg and placebo groups and slightly higher in the faldaprevir 240-mg group. Serious Aes were reported in 6%, 7%, and 8% of patients in placebo, faldaprevir 120-mg, and faldaprevir 240-mg groups, respectively.

CONCLUSION

Addition of faldaprevir to PegIFN/RBV increased SVR12 in patients with HCV genotype-1, and was well tolerated. Faldaprevir 120 mg is effective in the treatment of HCV genotype-1. ClinicalTrials.gov: NCT01343888 and NCT01297270.

The applicability of hepatocellular carcinoma risk prediction scores in a North American patient population with chronic hepatitis B infection

BACKGROUND

Patients with chronic hepatitis B (CHB) infection are at an increased risk of developing hepatocellular carcinoma (HCC). Risk scores have been developed in Asian populations to predict HCC risk over time.

AIM

To assess the performance of HCC risk prediction models in a heterogeneous population of patients with CHB.

METHODS

Scores were calculated at baseline using CU-HCC, REACH-B, NGM1-HCC, NGM2-HCC and GAG-HCC models and the incidence of HCC was determined. The predictive ability of each score was evaluated using the area under the receiver operating characteristic curve (AUROC), Cox regression and plots of observed versus predicted HCC. The predictive value of the scores was compared between Asian and non-Asian patients and between cirrhotic versus non-cirrhotic with and without treatment.

RESULTS

Of 2105 patients, 70 developed HCC. Increasing risk score was associated with HCC in all models. The CU-HCC model had the highest AUROC in Asian (0.85) and non-Asian (0.91) patients. Patients identified as low risk by any model had a very low incidence of HCC (0-0.15 per year), with the highest proportion of patients identified as low risk using CU-HCC (67%) or GAG-HCC (78%). The risk of HCC was similar to predicted for low-risk and medium-risk patients but was lower than predicted for high-risk patients. Treated patients had a lower than predicted risk of HCC, particularly in non-cirrhotic high-risk patients with longer follow-up.

CONCLUSIONS

Although all models predicted the risk of HCC, models that incorporated parameters of liver function or cirrhosis (CU-HCC/GAG-HCC) were most accurate. Low-risk patients likely require reduced HCC surveillance.

HCV Specific IL-21 Producing T Cells but Not IL-17A Producing T Cells Are Associated with HCV Viral Control in HIV/HCV Coinfection

BACKGROUND

Decreased hepatitis C virus (HCV) clearance, faster cirrhosis progression and higher HCV RNA levels are associated with Human Immunodeficiency virus (HIV) coinfection. The CD4+ T helper cytokines interleukin (IL)-21 and IL-17A are associated with virus control and inflammation, respectively, both important in HCV and HIV disease progression. Here, we examined how antigen-specific production of these cytokines during HCV mono and HIV/HCV coinfection was associated with HCV virus control.

METHODS

We measured HCV-specific IL-21 and IL-17A production by transwell cytokine secretion assay in PBMCs from monoinfected and coinfected individuals. Viral control was determined by plasma HCV RNA levels.

RESULTS

In acutely infected individuals, those able to establish transient/complete HCV viral control tended to have stronger HCV-specific IL-21-production than non-controllers. HCV-specific IL-21 production also correlated with HCV viral decline in acute infection. Significantly stronger HCV-specific IL-21 production was detected in HAART-treated coinfected individuals. HCV-specific IL-17A production was not associated with lower plasma HCV RNA levels in acute or chronic HCV infection and responses were stronger in HIV coinfection. HCV-specific IL-21/ IL-17A responses did not correlate with microbial translocation or fibrosis. Exogenous IL-21 treatment of HCV-specific CD8+ T cells from monoinfected individuals enhanced their function although CD8+ T cells from coinfected individuals were somewhat refractory to the effects of IL-21.

CONCLUSIONS

These data show that HCV-specific IL-21 and IL-17A-producing T cells are induced in HIV/HCV coinfection. In early HIV/HCV coinfection, IL-21 may contribute to viral control, and may represent a novel tool to enhance acute HCV clearance in HIV/HCV coinfected individuals.

Hepatitis B Virus--Specific and Global T-Cell Dysfunction in Chronic Hepatitis B

BACKGROUND & AIMS

T cells play a critical role in viral infection. We examined whether T-cell effector and regulatory responses can define clinical stages of chronic hepatitis B (CHB).

METHODS

We enrolled 200 adults with CHB who participated in the National Institutes of Health-supported Hepatitis B Research Network from 2011 through 2013 and 20 uninfected individuals (controls). Peripheral blood lymphocytes from these subjects were analyzed for T-cell responses (proliferation and production of interferon gamma and interleukin 10) to overlapping hepatitis B virus (HBV) peptides (preS, S, preC, core, and reverse transcriptase), influenza matrix peptides, and lipopolysaccharide. T-cell expression of regulatory markers FOXP3, programmed death-1, and cytotoxic T lymphocyte-associated antigen-4 was examined by flow cytometry. Immune measures were compared with clinical parameters, including physician-defined immune-active, immune-tolerant, or inactive CHB phenotypes, in a blinded fashion.

RESULTS

Compared with controls, patients with CHB had weak T-cell proliferative, interferon gamma, and interleukin 10 responses to HBV, with increased frequency of circulating FOXP3(+)CD127(-) regulatory T cells and CD4(+) T-cell expression of programmed death-1 and cytotoxic T lymphocyte-associated antigen-4. T-cell measures did not clearly distinguish between clinical CHB phenotypes, although the HBV core-specific T-cell response was weaker in hepatitis B e antigen (HBeAg)(+) than HBeAg(-) patients (percent responders: 3% vs 23%; P = .00008). Although in vitro blockade of programmed death-1 or cytotoxic T lymphocyte-associated antigen-4 increased T-cell responses to HBV, the effect was weaker in HBeAg(+) than HBeAg(-) patients. Furthermore, T-cell responses to influenza and lipopolysaccharide were weaker in CHB patients than controls.

CONCLUSIONS

HBV persists with virus-specific and global T-cell dysfunction mediated by multiple regulatory mechanisms, including circulating HBeAg, but without distinct T-cell-based immune signatures for clinical phenotypes. These findings suggest additional T-cell-independent or regulatory mechanisms of CHB pathogenesis that warrant further investigation.

Ledipasvir and Sofosbuvir for HCV in Patients Coinfected with HIV-1

BACKGROUND

Effective treatment for hepatitis C virus (HCV) in patients coinfected with human immunodeficiency virus type 1 (HIV-1) remains an unmet medical need.

METHODS

We conducted a multicenter, single-group, open-label study involving patients coinfected with HIV-1 and genotype 1 or 4 HCV receiving an antiretroviral regimen of tenofovir and emtricitabine with efavirenz, rilpivirine, or raltegravir. All patients received ledipasvir, an NS5A inhibitor, and sofosbuvir, a nucleotide polymerase inhibitor, as a single fixed-dose combination for 12 weeks. The primary end point was a sustained virologic response at 12 weeks after the end of therapy.

RESULTS

Of the 335 patients enrolled, 34% were black, 55% had been previously treated for HCV, and 20% had cirrhosis. Overall, 322 patients (96%) had a sustained virologic response at 12 weeks after the end of therapy (95% confidence interval [CI], 93 to 98), including rates of 96% (95% CI, 93 to 98) in patients with HCV genotype 1a, 96% (95% CI, 89 to 99) in those with HCV genotype 1b, and 100% (95% CI, 63 to 100) in those with HCV genotype 4. Rates of sustained virologic response were similar regardless of previous treatment or the presence of cirrhosis. Of the 13 patients who did not have a sustained virologic response, 10 had a relapse after the end of treatment. No patient had confirmed HIV-1 virologic rebound. The most common adverse events were headache (25%), fatigue (21%), and diarrhea (11%). No patient discontinued treatment because of adverse events.

CONCLUSIONS

Ledipasvir and sofosbuvir for 12 weeks provided high rates of sustained virologic response in patients coinfected with HIV-1 and HCV genotype 1 or 4. (Funded by Gilead Sciences; ION-4 ClinicalTrials.gov number, NCT02073656.).

Missed opportunities for hepatocellular carcinoma screening in an HIV/hepatitis C virus-coinfected cohort

We examined adherence to guidelines for screening of hepatocellular carcinoma in a cohort of HIV/hepatitis C virus-coinfected patients. Thirty-six percent of patients with documented cirrhosis did not have a screening ultrasound. Patients at centers with standardized systems for screening were more likely to have had an ultrasound performed.

Mixture model-based approach for optic cup segmentation

Glaucoma is a leading cause of blindness with permanent damage to optic nerve head. ARGALI is an automated computer-aided diagnosis system designed for glaucoma detection via optic cup-to-disc ratio assessment. It employs several methods to determine the optic cup and disc from retinal images.

Learning-based approach for the automatic detection of the optic disc in digital retinal fundus photographs

The optic disc is an important feature in the retina. We propose a method for the detection of the optic disc based on a supervised learning scheme. The method employs pixel and local neighbourhood features extracted from the ROI of a digital retinal fundus photograph. A support vector machine based classification mechanism is used to classify each image point as belonging to the cup and retina. The proposed method is evaluated on a sample image set of 68 retinal fundus images. The results show a high correlation (r>0.9) with the ground truth segmentation, with an overlap error of 6.02%, and found to be comparable to the inter-observer variability based on an independent second observer segmentation of the same data set.

Automatic detection of pathological myopia using variational level set

Pathological myopia, the seventh leading cause of legal blindness in United States, is a condition caused by pathological axial elongation and eyes that deviates from the normal distribution curve of axial length, resulting in impaired vision. Studies have shown that ocular risks associated with myopia should not be underestimated, and there is a public health need to prevent the onset or progression of myopia. Peripapillary atrophy (PPA) is one of the clinical indicators for pathological myopia. In this paper, we introduce a novel method, to detect pathological myopia via peripapaillary atrophy feature by means of variational level set. This method is a core algorithm of our system, PAMELA, an automated system for the detection of pathological myopia. The proposed method has been tested on 40 images from Singapore Cohort study Of the Risk factors for Myopia (SCORM), producing a 95% accuracy of correct assessment, and a sensitivity and specificity of 0.9 and 1 respectively. The results highlight the potential of PAMELA as a possible clinical tool for objective mass screening of pathological myopia.

Reduction in red blood cell transfusions among preterm infants: results of a randomized trial with an in-line blood gas and chemistry monitor

BACKGROUND

Critically ill, extremely premature infants develop anemia because of intensive laboratory blood testing and undergo multiple red blood cell (RBC) transfusions in the early weeks of life. To date, researchers have had only limited success in finding ways to reduce transfusions significantly in this patient population.

OBJECTIVE

To reduce RBC transfusions for these infants by using a point-of-care bedside monitor that returns analyzed blood to the patient.

DESIGN, SETTING, AND PATIENTS

This was a prospective, 2-center, randomized, open, controlled, clinical trial with a 1:1 assignment of extremely low birth weight infants (weighing 500-1000 g at birth) to control or monitor groups and analysis with the intention-to-treat approach. Predefined RBC transfusion criteria were applied uniformly in the 2 groups.

INTERVENTIONS

Clinical treatment of study subjects with an in-line, ex vivo, bedside monitor that withdraws blood through an umbilical artery catheter, analyzes blood gases and sodium, potassium, and hematocrit levels, and returns the sample to the patient.

MAIN OUTCOME MEASURES

The total volume and number of RBC transfusions during the first 2 weeks of life and the total volume of blood removed for laboratory testing.

RESULTS

The trial was terminated prematurely when one center's NICU changed its standard method of laboratory testing. In the first 2 weeks of life, there was a nonsignificant 17% lower cumulative RBC transfusion volume in the monitor group (n = 46), compared with the control group (n = 47). However, data from the first week only (the period of greater catheter use) demonstrated a significant 33% lower cumulative RBC transfusion volume in the monitor group. Cumulative phlebotomy loss was approximately 25% less in the monitor group throughout the 2-week study period. There was no difference between groups in neonatal mortality, morbidity, and neurodevelopmental outcome rates at 18 to 24 months. This is the first randomized trial documenting that RBC transfusions administered to neonates can by reduced by decreasing laboratory phlebotomy loss.

CONCLUSIONS

As long as an umbilical artery catheter is available for blood sampling with an in-line blood gas and chemistry monitor, significant reductions in neonatal RBC transfusions can be achieved. The patients most likely to benefit from monitor use are the smallest, most critically ill newborns.

An in vivo probe based on mechanically strong but structurally small carbon electrodes with an appreciable surface area

Physically small carbon electrodes were fabricated by pyrolyzing acetylene in a nitrogen atmosphere using pulled quartz capillaries as the supporting substrate. A carbon disk geometry was obtained when a parallel flow of acetylene (50 kPa) and nitrogen (10 mL min(-1)) was introduced into the system. Further, carbon was found to deposit at the tip and on the shank of the quartz capillaries when the nitrogen flow rate was increased (80 mL min(-1)), yielding an approximately cylindrical geometry. A series of electrochemical and spectroscopic analyses was carried out to examine the type of carbon surface obtained by pyrolysis of acetylene. The results suggested that a surface consisting of an almost defect-free highly oriented pyrolytic graphite type structure was formed by the pyrolyzed acetylene. However, this contradicts the kinetically reversible electron transfer observed for dopamine oxidation at these electrodes. Meanwhile, the nonpolar and relatively oxygen-free characteristics indicate that these electrodes also behave similarly to a hydrogenated carbon surface. The formation of a hydrogenated carbon-type surface may be plausible as a result of the attack on the carbon surface by a surplus of hydrogen produced by the pyrolysis of acetylene to form graphitic carbon. These characteristics are expected to aid in reducing electrode fouling, which is often encountered in electrochemical detection of neurotransmitters in vivo. In conjunction with a miniature physical dimension, their appreciable surface area and enhanced mechanical strength make these carbon electrodes well suited to the detection of neurotransmitters in vivo.

The plasmid-stabilizing ytl2 protein coats DNA in a sequence-independent manner

Plasmids carrying the ytl2 gene from the large resident plasmid pSLT of Salmonella typhimurium were stabilized >10(5)-fold (compared to control ytl2-free plasmids) in S. typhimurium cells. Purified Ytl2 protein was localized in the cell cytosol and bound to DNA in a sequence-independent manner to form a high-molecular-weight complex, suggesting cooperative binding to the DNA. A mutant ytl2 gene, with a modified C-terminus, did not mediate plasmid stabilization and the mutant Ytl2 protein did not bind cooperatively to DNA. In vivo, while a plasmid carrying the ytl2 gene was stabilized, another plasmid (lacking ytl2) coexisting in the same cell was not. This result suggests that the Ytl2 protein, newly synthesized in a transcription-translation complex, binds preferentially to DNA of the replicon which encodes it and that this binding initiates subsequent cooperative DNA coating by more Ytl2 molecules. Plasmid-encoded newly synthesized Ytl2 protein is thus unavailable to stabilize coresident plasmid DNA, which does not contain the ytl2 gene.

Detection of diverse hepatitis C virus (HCV)-specific cytotoxic T lymphocytes in peripheral blood of infected persons by screening for responses to all translated proteins of HCV

Broadly directed hepatitis C virus (HCV)-specific cytotoxic T lymphocytes (CTL) have been identified from liver-infiltrating lymphocytes but have been more difficult to assess in peripheral blood of infected persons. To enhance the detection of CTL from peripheral blood mononuclear cells (PBMC), we cocultured PBMC with autologous Epstein-Barr virus-transformed B-lymphoblastoid cell lines that had been infected with recombinant vaccinia virus constructs so that they expressed the entire translated polyprotein of HCV-H, a type 1a strain. These stimulated cells from HCV-infected as well as exposed seronegative persons were then cloned at limiting dilution and tested for HCV-specific CTL activity using a standard (51)Cr release assay. HCV-specific CTL were detected in PBMC from seven of nine persons with chronic hepatitis, including five of seven in whom CTL had previously been detected from liver biopsy specimens but not PBMC. In a single person with chronic HCV infection, CTL directed against as many as five different epitopes were detected in peripheral blood and were similar in specificity to those detected in liver tissue. This technique was used to evaluate eight subjects identified to be at high risk for HCV exposure due to continued injection drug abuse; no evidence of CTL in PBMC was found. We conclude that CTL can be detected in PBMC from the majority of persons with chronic HCV infection but are present at lower levels or absent in exposed but persistently seronegative persons. The high degree of concordance of HCV epitopes identified from liver and PBMC suggests that this strategy is a reasonable alternative to liver biopsy for characterizing the CTL response to HCV in chronically infected persons.

Spontaneous release of large packets of noradrenaline from sympathetic nerve terminals in rat mesenteric arteries in vitro

Continuous amperometry was used to monitor noradrenaline (NA) release from sympathetic nerves supplying rat mesenteric arteries in vitro. During electrical stimulation the amplitude of oxidation currents evoked by successive stimuli varied over a small range, with occasional events of larger amplitude. In the absence of stimulation, spontaneous oxidation currents (s.o.cs) were recorded. The frequency of s.o.cs was increased by alpha-latrotoxin (1 nM). This agent also increased the frequency of spontaneous excitatory junction potentials (s.e.j.ps), which monitor the packeted release of adenosine 5' triphosphate (ATP). The frequency of s.o.cs recorded 20-25 min after applying alpha-latrotoxin was about four times the control value, but that of s.e.j.ps was about 30 times the control value. The findings suggest that continuous amperometry can detect the spontaneous packeted release of NA, probably from large dense-cored vesicles. In contrast, s.e.j.ps monitor spontaneous release of neurotransmitter (ATP) from a different store, most likely the small dense-cored vesicles.

Salmonella enterica serovar typhi uses type IVB pili to enter human intestinal epithelial cells

DNA sequencing upstream of the Salmonella enterica serovar Typhi pilV and rci genes previously identified in the ca. 118-kb major pathogenicity island (X.-L. Zhang, C. Morris, and J. Hackett, Gene 202:139-146, 1997) identified a further 10 pil genes apparently forming a pil operon. The product of the pilS gene, prePilS protein (a putative type IVB structural prepilin) was purified, and an anti-prePilS antiserum was raised in mice. Mutants of serovar Typhi either lacking the whole pil operon or with an insertion mutation in the pilS gene were constructed, as was a strain in which the pilN to pilV genes were driven by the tac promoter. The pil(+) strains synthesized type IVB pili, as judged by (i) visualization in the electron microscope of thin pili in culture supernatants of one such strain and (ii) the presence of PilS protein (smaller than the prePilS protein by removal of the leader peptide) on immunoblotting of material pelleted by high-speed centrifugation of either the culture supernatant or sonicates of pil(+) strains. Control pil mutants did not express the PilS protein. A pilS mutant of serovar Typhi entered human intestinal INT407 cells in culture to levels only 5 to 25% of those of the wild-type strain, and serovar Typhi entry was strongly inhibited by soluble prePilS protein (50% inhibition of entry at 1.4 microM prePilS).

An indirect perfluorosulfonated ionomer-coated electrochemical immunosensor for the detection of the protein human chorionic gonadotrophin

The development of an amperometric immunosensor for the detection of human chorionic gonadotrophin (hCG) is described. In this immunosensor, Nafion was used to immobilize an anti-hCG monoclonal antibody onto a glassy carbon electrode. A systematic study on the effects of experimental parameters such as the quantity of ethanol present in the Nafion solution, the percentage composition of Nafion, the pH of the immobilization buffer, and the concentration of antibody used for entrapment experiments on the binding between the immobilized antibody and 125I-labeled hCG has been carried out. Two immobilization methods, coimmobilization and adsorption immobilization, have then been attempted. A binding of approximately 3% was obtained in the former method, while 5.5% binding was achieved in the latter. On the basis of these results, adsorption immobilization was employed to entrap antibody on the electrode surface. A sandwich assay was then developed for hCG in which the enzyme horseradish peroxidase was conjugated to a second anti-hCG monoclonal antibody. The activity of the enzyme was determined electrochemically by the reduction of benzoquinone to hydroquinone. Binding of hCG to immobilized antibody determines the quantity of enzyme-conjugated antibody at the electrode surface, permitting the quantification of hCG. By a standard additions calibration method of hCG performed in blank human serum samples, the immunosensor exhibits a limit of linearity at 200 mIU mL-1 and a detection limit of 11.2 mIU mL-1 (based on twice the standard deviation of the blank solution).

Long-term follow-up of a randomized trial of interferon therapy for chronic hepatitis B in a predominantly homosexual male population

BACKGROUND/AIMS

Extended follow-up of a previously published therapeutic trial with interferon alfa is now available to further clarify the long-term outcome of HIV-negative and HIV-positive subjects with chronic hepatitis B virus infection after interferon alfa therapy.

METHODS

Forty-five subjects with compensated liver disease and chronic hepatitis B infection with evidence of active hepatitis B replication were studied. These subjects were enrolled between 1986 and 1991 and had been randomized, stratified by HIV status, to either receive interferon therapy (10 MU/m2 of lymphoblastoid interferon alfa 3 times per week for 12 weeks) or no treatment. Hepatitis B serology, serum hepatitis B viral DNA and alanine aminotransferase were measured on an annual to biannual basis. CD4-positive T lymphocyte counts and HIV RNA concentration were also obtained.

RESULTS

From 9 months post-interferon alfa treatment to the end of the extended follow-up (4 to 9 years), the relative risk of seroconverting to anti-HBe positive for subjects who had received interferon alfa therapy compared to those who did not was not significant in either HIV-negative (p = 0.80) or HIV-positive (p = 0.62) subjects.

CONCLUSIONS

Unlike the first 9 months following interferon alfa therapy, the rate of elimination of markers of hepatitis B virus replication, regardless of HIV status, was not increased above the natural rate beyond 9 months following interferon alfa therapy.

Characterization of exochelins of the Mycobacterium bovis type strain and BCG substrains

Pathogenic mycobacteria must acquire iron in the host in order to multiply and cause disease. To do so, they release abundant quantities of siderophores called exochelins, which have the capacity to scavenge iron from host iron-binding proteins and deliver it to the mycobacteria. In this study, we have characterized the exochelins of Mycobacterium bovis, the causative agent of bovine and occasionally of human tuberculosis, and the highly attenuated descendant of M. bovis, bacillus Calmette-Guérin (BCG), widely used as a vaccine against human tuberculosis. The M. bovis type strain, five substrains of M. bovis BCG (Copenhagen, Glaxo, Japanese, Pasteur, and Tice), and two strains of virulent Mycobacterium tuberculosis all produce the same set of exochelins, although the relative amounts of individual exochelins may differ. Among these mycobacteria, the total amount of exochelins produced is greatest in M. tuberculosis, intermediate in M. bovis, and smallest in M. bovis BCG.

Identification of fur, aconitase, and other proteins expressed by Mycobacterium tuberculosis under conditions of low and high concentrations of iron by combined two-dimensional gel electrophoresis and mass spectrometry

Iron plays a critical role in the pathophysiology of Mycobacterium tuberculosis. To gain a better understanding of iron regulation by this organism, we have used two-dimensional (2-D) gel electrophoresis, mass spectrometry, and database searching to study protein expression in M. tuberculosis under conditions of high and low iron concentration. Proteins in cellular extracts from M. tuberculosis Erdman strain grown under low-iron (1 microM) and high-iron (70 microM) conditions were separated by 2-D polyacrylamide gel electrophoresis, which allowed high-resolution separation of several hundred proteins, as visualized by Coomassie staining. The expression of at least 15 proteins was induced, and the expression of at least 12 proteins was decreased under low-iron conditions. In-gel trypsin digestion was performed on these differentially expressed proteins, and the digestion mixtures were analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry to determine the molecular masses of the resulting tryptic peptides. Partial sequence data on some of the peptides were obtained by using after source decay and/or collision-induced dissociation. The fragmentation data were used to search computerized peptide mass and protein sequence databases for known proteins. Ten iron-regulated proteins were identified, including Fur and aconitase proteins, both of which are known to be regulated by iron in other bacterial systems. Our study shows that, where large protein sequence databases are available from genomic studies, the combined use of 2-D gel electrophoresis, mass spectrometry, and database searching to analyze proteins expressed under defined environmental conditions is a powerful tool for identifying expressed proteins and their physiologic relevance.

Liver-derived CTL in hepatitis C virus infection: breadth and specificity of responses in a cohort of persons with chronic infection

Hepatitis C virus (HCV)-specific CTL have been found within the inflammatory infiltrate of the liver of chronically infected individuals, but the breadth and specificity of the CTL response in relation to viral load are less well characterized. In this study, we analyzed the intrahepatic CTL response in liver biopsy specimens from 44 chronically infected subjects. Liver-infiltrating lymphocytes were expanded polyclonally in bulk cultures, and multiple clones were derived by limiting dilution. HCV-specific CTL responses directed at genotype 1a structural proteins were assessed in all subjects, and 22 subjects were tested more comprehensively using vectors expressing all structural and nonstructural HCV Ags. CTL responses were further characterized to determine the HLA restriction and optimal epitopes recognized. In those persons screened for recognition of all HCV Ags, HLA class I-restricted CTL were detected in 45%. Nineteen different CTL epitopes were identified, which were distributed throughout the genome; only one epitope was targeted by more than one person. In those persons with CTL responses, the breadth of response ranged from one to five epitopes. There was no correlation between the presence of a detectable CTL response and viral load. These results indicate considerable heterogeneity in detectable HCV-specific CTL responses in chronically infected persons. The mechanisms by which HCV persists during chronic infection remain to be clarified.

Hepatitis C virus-specific cytolytic T lymphocyte and T helper cell responses in seronegative persons

Hepatitis C virus (HCV) is a common infection worldwide, and in most persons, it leads to persistent viremia and liver damage. Efforts to identify the correlates of protective immunity are hampered by this high rate of persistent infection in both infected humans and the only animal model, the chimpanzee. Peripheral blood mononuclear cells from seronegative persons were stimulated with synthetic peptides that represent epitopes recognized by HCV-specific cytotoxic T lymphocytes (CTL) after natural infection. In addition, CD4+ proliferative responses to recombinant HCV proteins were examined in these same persons. CTL responses directed against a peptide epitope of HCV and proliferative responses in 2 HCV-seronegative persons with possible occupational exposure to HCV were found. These otherwise healthy persons were not viremic, suggesting that they may have recovered from acute HCV infection. Characterization of virus-specific immune responses in exposed but seronegative persons may provide important clues as to the nature of protective immunity in HCV.