Blood donation screening for hepatitis B virus core antibodies: The importance of confirmatory testing and initial implication for rare blood donor groups

BACKGROUND AND OBJECTIVES

Exclusion of blood donors with hepatitis B virus (HBV) core antibodies (anti-HBc) prevents transfusion-transmitted HBV infection but can lead to significant donor loss. As isolated anti-HBc positivity does not always indicate true past HBV infection, we have investigated the effectiveness of confirmatory anti-HBc testing and the representation of rare blood groups in anti-HBc-positive donors.

MATERIALS AND METHODS

Three hundred ninety-seven HBV surface antigen-negative and anti-HBc initially reactive blood donor samples were tested by five different anti-HBc assays.

RESULTS

Eighty percentage of samples reactive in Architect anti-HBc assay were positive by the Murex assay and anti-HBc neutralization. Eleven out of 397 samples showed discordant results in supplementary testing from the Murex confirmatory test result, and five remained undetermined following extensive serological testing. Thirty-eight percentage of anti-HBc-positive donors identified as minority ethnic groups compared with 11% representation in anti-HBc-negative donors (p < 0.0001); the frequency of the Ro blood group in anti-HBc-positive donors was 18 times higher in non-white ethnic groups.

CONCLUSION

Using two anti-HBc assays effectively enabled the identification of HBV-exposed and potentially infectious donors, their deferral and potential clinical follow-up. However, the exclusion of confirmed anti-HBc-positive donors will still impact the supply of rare blood such as Ro.

Increasing SARS-CoV-2 seroprevalence among UK pediatric patients on dialysis and kidney transplantation between January 2020 and August 2021

BACKGROUND

Coronavirus disease 2019 (COVID-19) was officially declared a pandemic by the World Health Organisation (WHO) on 11 March 2020, as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread rapidly across the world. We investigated the seroprevalence of anti-SARS-CoV-2 antibodies in pediatric patients on dialysis or kidney transplantation in the UK.

METHODS

Excess sera samples were obtained prospectively during outpatient visits or haemodialysis sessions and analysed using a custom immunoassay calibrated with population age-matched healthy controls. Two large pediatric centres contributed samples.

RESULTS

In total, 520 sera from 145 patients (16 peritoneal dialysis, 16 haemodialysis, 113 transplantation) were analysed cross-sectionally from January 2020 until August 2021. No anti-SARS-CoV-2 antibody positive samples were detected in 2020 when lockdown and enhanced social distancing measures were enacted. Thereafter, the proportion of positive samples increased from 5% (January 2021) to 32% (August 2021) following the emergence of the Alpha variant. Taking all patients, 32/145 (22%) were seropositive, including 8/32 (25%) with prior laboratory-confirmed SARS-CoV-2 infection and 12/32 (38%) post-vaccination (one of whom was also infected after vaccination). The remaining 13 (41%) seropositive patients had no known stimulus, representing subclinical cases. Antibody binding signals were comparable across patient ages and dialysis versus transplantation and highest against full-length spike protein versus spike subunit-1 and nucleocapsid protein.

CONCLUSIONS

Anti-SARS-CoV-2 seroprevalence was low in 2020 and increased in early 2021. Serological surveillance complements nucleic acid detection and antigen testing to build a greater picture of the epidemiology of COVID-19 and is therefore important to guide public health responses. A higher resolution version of the Graphical abstract is available as Supplementary information.

Ultrasensitive PCR system for HBV DNA detection: Risk stratification for occult hepatitis B virus infection in English blood donors

Occult hepatitis B (HBV) infection (OBI), characterized by low viral loads, accounts for much of the risk of HBV transfusion-transmitted infection. With anticore antibodies (anti-HBc) screening introduced in England, the imperative to identify OBI donors has increased. We aimed to develop an ultra-sensitive PCR system and investigate risk factors for HBV DNA presence in blood donations. Seven extraction methods and three PCR assays were compared. The optimal system was sought to determine HBV DNA presence in anti-HBc-positive donations. Predictors of DNA positivity were subsequently investigated. Extraction from 5 mL of plasma increased sample representation and resulted in HBV DNA detection in low viral load samples (~0.5 IU/mL). Screening of 487 763 donations in 2022 identified two OBI donors and 2042 anti-HBc-positive donors, 412 of the latter with anti-HBs < 100 mIU/mL. Testing of 134 anti-HBc-positive donations utilizing the 5 mL extraction method identified two further HBV DNA-positive donations. Higher anti-HBc titer and anti-HBs negativity were significant predictors of DNA detectability in anti-HBc-positive donations. An ultrasensitive PCR assay identified potentially infectious donations increasing HBV DNA detection in anti-HBc-positive donors from 0.5% to 1.9%. Anti-HBc titers may further complement the risk stratification for DNA positivity in anti-HBc screening and minimize unnecessary donor deferral.

Mortality rates among patients successfully treated for hepatitis C in the era of interferon-free antivirals: population based cohort study

OBJECTIVES

To quantify mortality rates for patients successfully treated for hepatitis C in the era of interferon-free, direct acting antivirals and compare these rates with those of the general population.

DESIGN

Population based cohort study.

SETTING

British Columbia, Scotland, and England (England cohort consists of patients with cirrhosis only).

PARTICIPANTS

21 790 people who were successfully treated for hepatitis C in the era of interferon-free antivirals (2014-19). Participants were divided into three liver disease severity groups: people without cirrhosis (pre-cirrhosis), those with compensated cirrhosis, and those with end stage liver disease. Follow-up started 12 weeks after antiviral treatment completion and ended on date of death or 31 December 2019.

MAIN OUTCOME MEASURES

Crude and age-sex standardised mortality rates, and standardised mortality ratio comparing the number of deaths with that of the general population, adjusting for age, sex, and year. Poisson regression was used to identify factors associated with all cause mortality rates.

RESULTS

1572 (7%) participants died during follow-up. The leading causes of death were drug related mortality (n=383, 24%), liver failure (n=286, 18%), and liver cancer (n=250, 16%). Crude all cause mortality rates (deaths per 1000 person years) were 31.4 (95% confidence interval 29.3 to 33.7), 22.7 (20.7 to 25.0), and 39.6 (35.4 to 44.3) for cohorts from British Columbia, Scotland, and England, respectively. All cause mortality was considerably higher than the rate for the general population across all disease severity groups and settings; for example, all cause mortality was three times higher among people without cirrhosis in British Columbia (standardised mortality ratio 2.96, 95% confidence interval 2.71 to 3.23; P<0.001) and more than 10 times higher for patients with end stage liver disease in British Columbia (13.61, 11.94 to 15.49; P<0.001). In regression analyses, older age, recent substance misuse, alcohol misuse, and comorbidities were associated with higher mortality rates.

CONCLUSION

Mortality rates among people successfully treated for hepatitis C in the era of interferon-free, direct acting antivirals are high compared with the general population. Drug and liver related causes of death were the main drivers of excess mortality. These findings highlight the need for continued support and follow-up after successful treatment for hepatitis C to maximise the impact of direct acting antivirals.

PRO-C3 is a predictor of clinical outcomes in distinct cohorts of patients with advanced liver disease

Background & Aims

Fibroblast activity is a key feature of fibrosis progression and organ function loss, leading to liver-related complications and mortality. The fibrogenesis marker, PRO-C3, has been shown to have prognostic significance in relation to fibrosis progression and as a treatment efficacy marker. We investigated whether PRO-C3 was prognostic for clinical outcome and mortality in two distinct cohorts of compensated cirrhosis.

Methods

Cohort 1 was a rapid fibrosis progression cohort including 104 patients with HCV and biopsy-proven Ishak fibrosis stage ≥3 without prior clinical events. Cohort 2 was a prospective cohort including 172 patients with compensated cirrhosis of mixed aetiology. Patients were assessed for clinical outcomes. PRO-C3 was assessed in serum at baseline in cohorts 1 and 2, and compared with model for end-stage liver disease and albumin-bilirubin (ALBI) scores.

Results

In cohort 1, a 2-fold increase in PRO-C3 was associated with 2.7-fold increased hazard of liver-related events (95% CI 1.6-4.6), whereas a one unit increase in ALBI score was associated with a 6.5-fold increased hazard (95% CI 2.9-14.6). In cohort 2, a 2-fold increase in PRO-C3 was associated with a 2.7-fold increased hazard (95% CI 1.8-3.9), whereas a one unit increase in ALBI score was associated with a 6.3-fold increased hazard (95% CI 3.0-13.2). A multivariable Cox regression analysis identified PRO-C3 and ALBI as being independently associated with the hazard of liver-related outcomes.

Conclusions

PRO-C3 and ALBI were independent prognostic factors for predicting liver-related clinical outcomes. Understanding the dynamic range of PRO-C3 might enhance its use for both drug development and clinical practice.

Impact and Implications

We tested novel proteins of liver scarring (PRO-C3) in two groups of liver patients with advanced disease to see if they could predict clinical events. We found that this marker and an established test called ALBI were both independently associated with future liver-related clinical outcomes.

Delivery of biannual ultrasound surveillance for individuals with cirrhosis and cured hepatitis C in the UK

BACKGROUND

Previous studies show the uptake of biannual ultrasound (US) surveillance in patients with cirrhosis is suboptimal. Here, our goal was to understand in broader terms how surveillance is being delivered to cirrhosis patients with cured hepatitis C in the UK.

METHODS

Hepatitis C cirrhosis patients achieving a sustained viral response (SVR) to antiviral therapies were identified from the national Hepatitis-C-Research-UK resource. Data on (i) liver/abdominal US examinations, (ii) HCC diagnoses, and (iii) HCC curative treatment were obtained through record-linkage to national health registries. The rate of US uptake was calculated by dividing the number of US episodes by follow-up time.

RESULTS

A total of 1908 cirrhosis patients from 31 liver centres were followed for 3.8 (IQR: 3.4-4.9) years. Overall, 10 396 liver/abdominal USs were identified. The proportion with biannual US was 19% in the first 3 years after SVR and 9% for all follow-up years. Higher uptake of biannual US was associated with attending a liver transplant centre; older age and cirrhosis decompensation. Funnel plot analysis indicated significant inter-centre variability in biannual US uptake, with 6/29 centres outside control limits. Incident HCC occurred in 133 patients, of which 49/133 (37%) were treated with curative intent. The number of US episodes in the two years prior to HCC diagnosis was significantly associated with higher odds of curative-intent treatment (aOR: 1.53; 95% CI: 1.12-2,09; p = .007).

CONCLUSIONS

This study provides novel data on the cascade of care for HCC in the UK. Our findings suggest biannual US is poorly targeted, inefficient and is not being delivered equitably to all patients.

Geographical variation in hepatitis C-related severe liver disease and patient risk factors: a multicentre cross-sectional study

Despite promising steps towards the elimination of hepatitis C virus (HCV) in the UK, several indicators provide a cause for concern for future disease burden. We aimed to improve understanding of geographical variation in HCV-related severe liver disease and historic risk factor prevalence among clinic attendees in England and Scotland. We used metadata from 3829 HCV-positive patients consecutively enrolled into HCV Research UK from 48 hospital centres in England and Scotland during 2012-2014. Employing mixed-effects statistical modelling, several independent risk factors were identified: age 46-59 y (ORadj 3.06) and ≥60 y (ORadj 5.64) relative to <46 y, male relative to female sex (ORadj 1.58), high BMI (ORadj 1.73) and obesity (ORadj 2.81) relative to normal BMI, diabetes relative to no diabetes (ORadj 2.75), infection with HCV genotype (GT)-3 relative to GT-1 (ORadj 1.75), route of infection through blood products relative to injecting drug use (ORadj 1.40), and lower odds were associated with black ethnicity (ORadj 0.31) relative to white ethnicity. A small proportion of unexplained variation was attributed to differences between hospital centres and local health authorities. Our study provides a baseline measure of historic risk factor prevalence and potential geographical variation in healthcare provision, to support ongoing monitoring of HCV-related disease burden and the design of risk prevention measures.

Hepatitis C subtyping assay failure in UK patients born in sub-Saharan Africa: Implications for global treatment and elimination

BACKGROUND AND AIMS: The newly developed direct-acting antivirals have revolutionized the treatment of chronic hepatitis C virus (HCV), with cure rates as high as 98% in some cohorts. Although genome sequencing has demonstrated that some subtypes of HCV naturally harbor drug resistance associated substitutions (RAS), these are often overlooked as "rarities." Furthermore, commercial subtyping assays and associated epidemiological findings are skewed towards Western cohorts and whole-genome sequencing can be problematic to deploy without significant infrastructure and training support. We thus aimed to develop a simple, robust and accurate HCV subtyping pipeline, to optimize and streamline molecular detection and sequence-based typing of diverse RAS-containing subtypes.

METHODS

HCV serum derived from 146 individuals, whose likely source of infection was from sub-Saharan Africa (SSA) was investigated with a novel panel of single round polymerase chain reaction (PCR) assays targeting NS5B and NS5A genomic regions. Virus subtype assignments were determined by pairwise-distance analysis and compared to both diagnostic laboratory assignments and free-to-use online typing tools.

RESULTS

Partial NS5A and NS5B sequences were respectively obtained from 131 to 135 HCV-positive patients born in 19 different countries from SSA but attending clinics in the UK. We determined that routine clinical diagnostic methods incorrectly subtyped 59.0% of samples, with a further 6.8% incorrectly genotyped. Of five commonly used online tools, Geno2Pheno performed most effectively in determining a subtype in agreement with pairwise distance analysis.

CONCLUSION

This study provides a simple low-cost pathway to accurately subtype in SSA, guide regional therapeutic choice and assist global surveillance and elimination initiatives.

Scavenger receptor class B type I genetic variants associated with disease severity in chronic hepatitis C virus infection

Analysis of host genetic polymorphisms is an increasingly important tool for understanding and predicting pathogenesis and treatment response of viral diseases. The gene locus of scavenger receptor class B type I (SR-BI), encoding a cell entry factor and receptor for hepatitis C virus (HCV), contains several genetic polymorphisms. We applied a probe extension assay to determine the frequency of six single nucleotide polymorphisms (SNPs) within the SR-BI gene locus in 374 individuals with history of HCV infection. In addition, SR-BI messenger RNA (mRNA) levels were analyzed in liver biopsy specimens of chronically infected HCV subjects. The rs5888 variant allele T was present at a higher frequency in subjects with advanced fibrosis (χ² , p = 0.016) and after adjusting for age, duration of infection and alcohol intake as confounding factors. Haplotype analysis of SNP frequencies showed that a haplotype consisting of rs61932577 variant allele C and rs5888 variant allele T was associated with an increased risk of advanced liver fibrosis (defined by an Ishak score 4-6) (adjusted odds ratio 2.81; 95% confidence interval 1.06-7.46. p = 0.038). Carriers of the rs5888 variant allele T displayed reduced SR-BI mRNA expression in liver biopsy specimens. In conclusion the rs5888 polymorphism variant is associated with decreased SR-BI expression and an increased risk of development of advanced fibrosis in chronic HCV infection. These findings provide further evidence for a role of SR-BI in HCV pathogenesis and provides a genetic marker for prediction of those infected individuals at greater risk of developing severe disease.

Human parainfluenza 2 &amp; 4: Clinical and genetic epidemiology in the UK, 2013-2017, reveals distinct disease features and co-circulating genomic subtypes

BACKGROUND

Human Parainfluenza viruses (HPIV) comprise of four members of the genetically distinct genera of Respirovirus (HPIV1&amp;3) and Orthorubulavirus (HPIV2&amp;4), causing significant upper and lower respiratory tract infections worldwide, particularly in children. However, despite frequent molecular diagnosis, they are frequently considered collectively or with HPIV4 overlooked entirely. We therefore investigated clinical and viral epidemiological distinctions of the relatively less prevalent Orthorubulaviruses HPIV2&amp;4 at a regional UK hospital across four autumn/winter epidemic seasons.

METHODS

A retrospective audit of clinical features of all HPIV2 or HPIV4 RT-PCR-positive patients, diagnosed between 1st September 2013 and 12th April 2017 was undertaken, alongside sequencing of viral genome fragments in a representative subset of samples.

RESULTS

Infection was observed across all age groups, but predominantly in children under nine and adults over 40, with almost twice as many HPIV4 as HPIV2 cases. Fever, abnormal haematology, elevated C-reactive protein and hospital admission were more frequently seen in HPIV2 than HPIV4 infection. Each of the four seasonal peaks of either HPIV2, HPIV4 or both, closely matched that of RSV, occurring in November and December and preceding that of Influenza A. A subset of viruses were partially sequenced, indicating co-circulation of multiple subtypes of both HPIV2&amp;4, but with little variation between each epidemic season or from limited global reference sequences.

CONCLUSIONS

Despite being closest known genetic relatives, our data indicates a potential difference in associated disease between HPIV2 and HPIV4, with more hospitalisation seen in HPIV2 mono-infected individuals, but a greater overall number of HPIV4 cases.

Enterovirus D68 epidemic, UK, 2018, was caused by subclades B3 and D1, predominantly in children and adults, respectively, with both subclades exhibiting extensive genetic diversity

Enterovirus D68 (EV-D68) has recently been identified in biennial epidemics coinciding with diagnoses of non-polio acute flaccid paralysis/myelitis (AFP/AFM). We investigated the prevalence, genetic relatedness and associated clinical features of EV-D68 in 193 EV-positive samples from 193 patients in late 2018, UK. EV-D68 was detected in 83 (58 %) of 143 confirmed EV-positive samples. Sequencing and phylogenetic analysis revealed extensive genetic diversity, split between subclades B3 (n=50) and D1 (n=33), suggesting epidemiologically unrelated infections. B3 predominated in children and younger adults, and D1 in older adults and the elderly (P=0.0009). Clinical presentation indicated causation or exacerbation of respiratory distress in 91.4 % of EV-D68-positive individuals, principally cough (75.3 %), shortness of breath (56.8 %), coryza (48.1 %), wheeze (46.9 %), supplemental oxygen required (46.9 %) and fever (38.9 %). Two cases of AFM were observed, one with EV-D68 detectable in the cerebrospinal fluid, but otherwise neurological symptoms were rarely reported (n=4). Both AFM cases and all additional instances of intensive care unit (ICU) admission (n=5) were seen in patients infected with EV-D68 subclade B3. However, due to the infrequency of severe infection in our cohort, statistical significance could not be assessed.

Sero-reactivity to three distinct regions within the hepatitis C virus alternative reading frame protein (ARFP/core+1) in patients with chronic HCV genotype-3 infection

Hepatitis C virus (HCV) infection affects more than 71 million people worldwide. The disease slowly progresses to chronic, long-term liver injury which leads to hepatocellular carcinoma (HCC) in 5 % of infections. The alternative reading frame protein (ARFP/core+1) is encoded by a sequence overlapping the HCV core gene in the +1 reading frame. Its role in hepatitis C pathogenesis and the viral life cycle is unclear, although some observers have related its production to disease progression and the development of HCC. The aim of this study was to determine whether ARFP is immunogenic in patients with chronic HCV genotype 3 infection and to assess whether sero-reactivity is associated with disease progression, particularly to HCC. Immunogenic epitopes within the protein were predicted by a bioinformatics tool, and three -20 aa length-peptides (ARFP-P1, ARFP-P2 and ARFP-P3) were synthesized and used in an avidin-biotin ARFP/core+1 peptide ELISA. Serum samples from 50 patients with chronic HCV genotype 3 infection, 50 genotype-1 patients, 50 HBV patients and 110 healthy controls were tested. Sero-reactivity to the ARFP peptides was also tested and compared in 114 chronic HCV genotype-3 patients subdivided on the basis of disease severity into non-cirrhotic, cirrhotic and HCC groups. Chronic HCV genotype-3 patients showed noticeable rates of reactivity to ARFP and core peptides. Seropositivity rates were 58% for ARFP-P1, 47 % for ARFP-P2, 5.9 % for ARFP-P3 and 100 % for C22 peptides. There was no significant difference between these seroreactivities between HCV genotype-3 patients with HCC, and HCV genotype-3 patients with and without liver cirrhosis. Patients with chronic HCV genotype-3 infection frequently produce antibodies against ARFP/core+1 protein. ARFP peptide reactivity was not associated with disease severity in patients with HCV genotype-3. These results support the conclusion that ARFP/core+1 is produced during HCV infection, but they do not confirm that antibodies to ARFP can indicate HCV disease progression.

Comprehensive Comparative Analysis of Standard Validated, Genetic, and Novel Biomarkers to Enhance Prognostic Risk-Stratification in Patients With Hepatitis C Virus Cirrhosis

INTRODUCTION

Risk-stratifying patients with hepatitis C virus (HCV) cirrhosis according to medium-term prognosis will inform clinical decision-making. It is unclear which biomarkers/models are optimal for this purpose. We quantified the discriminative ability of 14 diverse biomarkers for prognosis prediction over a 4-year time.

METHODS

We recruited 1196 patients with HCV cirrhosis from the United Kingdom for a prospective study. Genetic risk score, collagen (e.g., PROC3), comorbidity (e.g., CirCom), and validated biomarkers from routine data were measured at enrollment. Participants were linked to UK hospital admission, cancer, and mortality registries. Primary endpoints were (i) liver-related outcomes for patients with compensated cirrhosis and (ii) all-cause mortality for decompensated cirrhosis. The discriminative ability of all biomarkers was quantified individually and also by the fraction of new prognostic information provided.

RESULTS

At enrollment, 289 (24%) and 907 (76%) had decompensated and compensated cirrhosis, respectively. Participants were followed for 3-4 years on average, with >70% of the follow-up time occurring post-HCV cure. Seventy-five deaths in the decompensated subgroup and 98 liver-related outcomes in the compensated subgroup were reported. The discriminative ability of the albumin-bilirubin-fibrosis-4 index (C-index: 0.71-0.72) was superior to collagen biomarkers (C-index = 0.58-0.67), genetic risk scores (C-index = 0.50-0.57), and comorbidity markers (0.53-0.60). Validated biomarkers showed the greatest prognostic improvement when combined with a comorbidity or a collagen biomarker (generally >30% of new prognostic information added).

DISCUSSION

Inexpensive biomarkers such as the albumin-bilirubin-fibrosis-4 index predict medium-term cirrhosis prognosis moderately well and outperform collagen, genetic, and comorbidity biomarkers. Improvement of performance was greatest when a validated test was combined with comorbidity or collagen biomarker.

The Impact of Real-Time Whole-Genome Sequencing in Controlling Healthcare-Associated SARS-CoV-2 Outbreaks

Nosocomial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have severely affected bed capacity and patient flow. We utilized whole-genome sequencing (WGS) to identify outbreaks and focus infection control resources and intervention during the United Kingdom's second pandemic wave in late 2020. Phylogenetic analysis of WGS and epidemiological data pinpointed an initial transmission event to an admission ward, with immediate prior community infection linkage documented. High incidence of asymptomatic staff infection with genetically identical viral sequences was also observed, which may have contributed to the propagation of the outbreak. WGS allowed timely nosocomial transmission intervention measures, including admissions ward point-of-care testing and introduction of portable HEPA14 filters. Conversely, WGS excluded nosocomial transmission in 2 instances with temporospatial linkage, conserving time and resources. In summary, WGS significantly enhanced understanding of SARS-CoV-2 clusters in a hospital setting, both identifying high-risk areas and conversely validating existing control measures in other units, maintaining clinical service overall.

Serum levels of pro-inflammatory lipid mediators and specialised pro-resolving molecules are increased in SARS-CoV-2 patients and correlate with markers of the adaptive immune response

Background

Specialized proresolution molecules (SPMs) halt the transition to chronic pathogenic inflammation. We aimed to quantify serum levels of pro- and anti-inflammatory bioactive lipids in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) patients, and to identify potential relationships with innate responses and clinical outcome.

Methods

Serum from 50 hospital admitted inpatients (22 female, 28 male) with confirmed symptomatic SARS-CoV-2 infection and 94 age- and sex-matched controls collected prior to the pandemic (SARS-CoV-2 negative), were processed for quantification of bioactive lipids and anti-nucleocapsid and anti-spike quantitative binding assays.

Results

SARS-CoV-2 serum had significantly higher concentrations of omega-6–derived proinflammatory lipids and omega-6– and omega-3–derived SPMs, compared to the age- and sex-matched SARS-CoV-2–negative group, which were not markedly altered by age or sex. There were significant positive correlations between SPMs, proinflammatory bioactive lipids, and anti-spike antibody binding. Levels of some SPMs were significantly higher in patients with an anti-spike antibody value >0.5. Levels of linoleic acid and 5,6-dihydroxy-8Z,11Z,14Z-eicosatrienoic acid were significantly lower in SARS-CoV-2 patients who died.

Conclusions

SARS-CoV-2 infection was associated with increased levels of SPMs and other pro- and anti-inflammatory bioactive lipids, supporting the future investigation of the underlying enzymatic pathways, which may inform the development of novel treatments.

Immunocompromised children and young people are at no increased risk of severe COVID-19

OBJECTIVES

We aimed to prospectively describe the incidence and clinical spectrum of SARS-CoV-2 infection in immunocompromised paediatric patients in the UK.

METHODS

From March 2020 to 2021 weekly questionnaires were sent to immunocompromised paediatric patients or their parents. Information, including symptom presentation and SARS-CoV-2 PCR test results, was collected from 1527 participants from 46 hospitals. Cross-sectional serology was investigated in February and March 2021.

RESULTS

Until the end of September 2020, no cases were reported. From September 28th 2020 to March 2021 a total of 38 PCR-detected SARS-CoV-2 infections were reported. Of these, four children were admitted to hospital but none had acute severe COVID-19. Increasing age in association with immunodeficiency increased reporting of SARS-CoV-2 infection. Worsening of fever, cough, and sore throat were associated with participants reporting SARS-CoV-2 infection. Serology data included 452 unvaccinated participants. In those reporting prior positive SARS-CoV-2 PCR, there were detectable antibodies in 9 of 18 (50%). In those with no prior report of infection, antibodies were detected in 32 of 434 (7•4%).

CONCLUSIONS

This study shows SARS-CoV-2 infections have occurred in immunocompromised children and young people with no increased risk of severe disease. No children died.

Viral genome wide association study identifies novel hepatitis C virus polymorphisms associated with sofosbuvir treatment failure

Persistent hepatitis C virus (HCV) infection is a major cause of chronic liver disease, worldwide. With the development of direct-acting antivirals, treatment of chronically infected patients has become highly effective, although a subset of patients responds less well to therapy. Sofosbuvir is a common component of current de novo or salvage combination therapies, that targets the HCV NS5B polymerase. We use pre-treatment whole-genome sequences of HCV from 507 patients infected with HCV subtype 3a and treated with sofosbuvir containing regimens to detect viral polymorphisms associated with response to treatment. We find three common polymorphisms in non-targeted HCV NS2 and NS3 proteins are associated with reduced treatment response. These polymorphisms are enriched in post-treatment HCV sequences of patients unresponsive to treatment. They are also associated with lower reductions in viral load in the first week of therapy. Using in vitro short-term dose-response assays, these polymorphisms do not cause any reduction in sofosbuvir potency, suggesting an indirect mechanism of action in decreasing sofosbuvir efficacy. The identification of polymorphisms in NS2 and NS3 proteins associated with poor treatment outcomes emphasises the value of systematic genome-wide analyses of viruses in uncovering clinically relevant polymorphisms that impact treatment.

Real world SOF/VEL/VOX retreatment outcomes and viral resistance analysis for HCV patients with prior failure to DAA therapy

Sustained viral response (SVR) rates for direct-acting antiviral (DAA) therapy for hepatitis C virus (HCV) infection routinely exceed 95%. However, a small number of patients require retreatment. Sofosbuvir, velpatasvir and voxilaprevir (SOF/VEL/VOX) is a potent DAA combination primarily used for the retreatment of patients who failed by DAA therapies. Here we evaluate retreatment outcomes and the effects of resistance-associated substitutions (RAS) in a real-world cohort, including a large number of genotype (GT)3 infected patients. 144 patients from the UK were retreated with SOF/VEL/VOX following virologic failure with first-line DAA treatment regimens. Full-length HCV genome sequencing was performed prior to retreatment with SOF/VEL/VOX. HCV subtypes were assigned and RAS relevant to each genotype were identified. GT1a and GT3a each made up 38% (GT1a n = 55, GT3a n = 54) of the cohort. 40% (n = 58) of patients had liver cirrhosis of whom 7% (n = 4) were decompensated, 10% (n = 14) had hepatocellular carcinoma (HCC) and 8% (n = 12) had received a liver transplant prior to retreatment. The overall retreatment SVR12 rate was 90% (129/144). On univariate analysis, GT3 infection (50/62; SVR = 81%, p = .009), cirrhosis (47/58; SVR = 81%, p = .01) and prior treatment with SOF/VEL (12/17; SVR = 71%, p = .02) or SOF+DCV (14/19; SVR = 74%, p = .012) were significantly associated with retreatment failure, but existence of pre-retreatment RAS was not when viral genotype was taken into account. Retreatment with SOF/VEL/VOX is very successful for non-GT3-infected patients. However, for GT3-infected patients, particularly those with cirrhosis and failed by initial SOF/VEL treatment, SVR rates were significantly lower and alternative retreatment regimens should be considered.

Retrospective screening of routine respiratory samples revealed undetected community transmission and missed intervention opportunities for SARS-CoV-2 in the United Kingdom

In the early phases of the SARS coronavirus type 2 (SARS-CoV-2) pandemic, testing focused on individuals fitting a strict case definition involving a limited set of symptoms together with an identified epidemiological risk, such as contact with an infected individual or travel to a high-risk area. To assess whether this impaired our ability to detect and control early introductions of the virus into the UK, we PCR-tested archival specimens collected on admission to a large UK teaching hospital who retrospectively were identified as having a clinical presentation compatible with COVID-19. In addition, we screened available archival specimens submitted for respiratory virus diagnosis, and dating back to early January 2020, for the presence of SARS-CoV-2 RNA. Our data provides evidence for widespread community circulation of SARS-CoV-2 in early February 2020 and into March that was undetected at the time due to restrictive case definitions informing testing policy. Genome sequence data showed that many of these early cases were infected with a distinct lineage of the virus. Sequences obtained from the first officially recorded case in Nottinghamshire - a traveller returning from Daegu, South Korea - also clustered with these early UK sequences suggesting acquisition of the virus occurred in the UK and not Daegu. Analysis of a larger sample of sequences obtained in the Nottinghamshire area revealed multiple viral introductions, mainly in late February and through March. These data highlight the importance of timely and extensive community testing to prevent future widespread transmission of the virus.

Comparison of the Prognosis of Decompensated Cirrhosis in Patients with and Without Eradication of Hepatitis C Virus

Introduction

In patients with hepatitis C virus (HCV) infection and decompensated cirrhosis (DC), it is uncertain whether viral clearance is clinically meaningful and whether it decreases liver-related and non-liver-related mortality. The aim of this study was to assess whether viral eradication reduced liver-related and non-liver-related mortality in patients with HCV infection and DC.

Methods

To clarify the impact of viral eradication on liver-related and non-liver-related mortality, 364 patients with DC who received direct-acting antivirals (DAAs) and achieved sustained virological response (SVR) in the UK (DAA group) were compared with 249 patients with DC who did not receive DAAs and who underwent symptomatic treatment in Japan (non-DAA group). Propensity score matching and inverse probability weighting (IPW) were performed to adjust the baseline characteristics in the DAA and non-DAA groups. Liver-related and non-liver-related mortality were analyzed using the competing risks IPW cumulative incidence functions estimator.

Results

The cumulative all-cause mortality rate in the DAA group was significantly lower than that in the non-DAA group (p < 0.0001, IPW-adjusted log-rank test). The cumulative incidence rates of both liver-related and non-liver-related mortality were significantly lower in the DAA group than those in the non-DAA group (p < 0.0001 for both).

Conclusion

DAA-mediated viral eradication reduced not only liver-related mortality but also non-liver-related mortality in patients with HCV infection and DC.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-021-00441-7.

Real-World Outcomes of DAA Treatment and Retreatment in UK-based Patients Infected with HCV Genotypes/Subtypes Endemic in Africa

Background

Chronic hepatitis C virus (HCV) infection affects 71 million individuals, mostly residing in low- and middle-income countries (LMICs). Direct-acting antivirals (DAAs) give high rates of sustained virological response (SVR) in high-income countries where a restricted range of HCV genotypes/subtypes circulate.

Methods

We studied United Kingdom–resident patients born in Africa to examine DAA effectiveness in LMICs where there is far greater breadth of HCV genotypes/subtypes. Viral genome sequences were determined from 233 patients.

Results

Full-length viral genomic sequences for 26 known subtypes and 5 previously unidentified isolates covering 5 HCV genotypes were determined. From 149 patients who received DAA treatment/retreatment, the overall SVR was 93%. Treatment failure was associated primarily with 2 subtypes, gt1l and gt4r, using sofosbuvir/ledipasvir. These subtypes contain natural resistance-associated variants that likely contribute to poor efficacy with this drug combination. Treatment failure was also significantly associated with hepatocellular carcinoma.

Conclusions

DAA combinations give high SVR rates despite the high HCV diversity across the African continent except for subtypes gt1l and gt4r, which respond poorly to sofosbuvir/ledipasvir. These subtypes are widely distributed across Western, Central, and Eastern Africa. Thus, in circumstances where accurate genotyping is absent, ledipasvir and its generic compounds should not be considered as a recommended treatment option.

Impact of direct-acting antiviral agents on liver function in patients with chronic hepatitis C virus infection

Whilst the benefit of direct-acting antiviral agents (DAAs) in achieving sustained virological response (SVR) is now well-accepted, their impact on liver function, particularly in relation to achievement of SVR, has not been well documented. We studied 2394 patients with chronic HCV infection, 1276 receiving DAAs and 1118 interferon-based therapy. Liver function was assessed by the albumin-bilirubin (ALBI) score or grade. Overall survival according to SVR status and baseline ALBI grade was examined. We also studied time to first decompensation according to ALBI grade, as well as longitudinal changes in ALBI score over time according to SVR. Among the patients receiving DAAs, 89% achieved SVR (Japan = 99%, UK = 78%). Amongst the decompensated patients in the UK cohort, three distinct risk groups according to ALBI grade at baseline were observed. The UK patients receiving DAAs, who had predominantly decompensated disease, showed clear evidence of improvement of liver function detectable within 2 years of the start of treatment, especially in those achieving SVR. These early changes in liver function were very similar to those observed in the first 2-3 years after interferon-based therapy. DAAs improve liver function especially in those with decompensated disease who achieve SVR. Experience with interferon-based therapy suggests that failure to achieve SVR is associated with long-term decline in liver function and, in contrast, patients who do achieve SVR can expect long-term disease improvement and subsequent stabilization of liver function. Our initial analysis suggests that those receiving DAAs are likely, in the long term, to follow a similar course.

aMAP risk score predicts hepatocellular carcinoma development in patients with chronic hepatitis

BACKGROUND & AIMS

Hepatocellular carcinoma (HCC) is the leading cause of death in patients with chronic hepatitis. In this international collaboration, we sought to develop a global universal HCC risk score to predict the HCC development for patients with chronic hepatitis.

METHODS

A total of 17,374 patients, comprising 10,578 treated Asian patients with chronic hepatitis B (CHB), 2,510 treated Caucasian patients with CHB, 3,566 treated patients with hepatitis C virus (including 2,489 patients with cirrhosis achieving a sustained virological response) and 720 patients with non-viral hepatitis (NVH) from 11 international prospective observational cohorts or randomised controlled trials, were divided into a training cohort (3,688 Asian patients with CHB) and 9 validation cohorts with different aetiologies and ethnicities (n = 13,686).

RESULTS

We developed an HCC risk score, called the aMAP score (ranging from 0 to 100), that involves only age, male, albumin-bilirubin and platelets. This metric performed excellently in assessing HCC risk not only in patients with hepatitis of different aetiologies, but also in those with different ethnicities (C-index: 0.82-0.87). Cut-off values of 50 and 60 were best for discriminating HCC risk. The 3- or 5-year cumulative incidences of HCC were 0-0.8%, 1.5-4.8%, and 8.1-19.9% in the low- (n = 7,413, 43.6%), medium- (n = 6,529, 38.4%), and high-risk (n = 3,044, 17.9%) groups, respectively. The cut-off value of 50 was associated with a sensitivity of 85.7-100% and a negative predictive value of 99.3-100%. The cut-off value of 60 resulted in a specificity of 56.6-95.8% and a positive predictive value of 6.6-15.7%.

CONCLUSIONS

This objective, simple, reliable risk score based on 5 common parameters accurately predicted HCC development, regardless of aetiology and ethnicity, which could help to establish a risk score-guided HCC surveillance strategy worldwide.

LAY SUMMARY

In this international collaboration, we developed and externally validated a simple, objective and accurate prognostic tool (called the aMAP score), that involves only age, male, albumin-bilirubin and platelets. The aMAP score (ranged from 0 to 100) satisfactorily predicted the risk of hepatocellular carcinoma (HCC) development among over 17,000 patients with viral and non-viral hepatitis from 11 global prospective studies. Our findings show that the aMAP score had excellent discrimination and calibration in assessing the 5-year HCC risk among all the cohorts irrespective of aetiology and ethnicity.

Enterovirus subtyping in a routine UK laboratory setting between 2013 and 2017

BACKGROUND

Human enteroviruses (EV) are the leading cause of viral meningitis. EV genotyping is predominantly performed through amplification and sequencing of viral capsid protein-1 (VP1), frequently by national reference laboratories (NRLs).

OBJECTIVE

To determine the frequency of genotyping failure in our NRL-submitted samples and apply a superior alternative assay to resolve untyped specimens.

STUDY DESIGN

We initially audited genotyping data received for a cohort of patients in the East Midlands, UK by the NRL between 2013 and 2017, then identified an alternative RT-PCR typing method by literature review and evaluated primers from both assays in silico against comprehensive publicly available genomic data. The alternative assay was further optimised and applied to archived nucleic acids from previously untypable samples.

RESULTS

Genotyping data showed a significant increase in untypable EV strains through the study period (p = 0.0073). Typing failure appeared unrelated to sample type or viral load. In silico analyses of 2,201 EV genomes showed high levels of mismatch between reference assay primers and clinically significant EV-species, in contrast to a selected alternative semi-nested RT-PCR VP1-typing assay. This alternative assay, with minor modifications, successfully genotyped 23 of 24 previously untypable yet viable archived specimens (EV-A, n = 4; EV-B, n = 19). Phylogenetic analyses identified no predominant strain within NRL untypable isolates, suggesting sub-optimal reference assay sensitivity across EV species, in agreement with in silico analyses.

CONCLUSION

This modified highly sensitive RT-PCR assay presents a suitable alternative to the current English national reference VP1-typing assay and is recommended in other settings experiencing typing failure.

Nanopore sequencing from extraction-free direct PCR of dried serum spots for portable hepatitis B virus drug-resistance typing

BACKGROUND

Effective drug regimens for the treatment of hepatitis B virus (HBV) infections are essential to achieve the World Health Organisation commitment to eliminate viral hepatitis by 2030. Lamivudine (3TC) is widely used in countries with high levels of chronic HBV, however resistance has been shown to occur in up to 50 % of individuals receiving continuous monotherapy for 4 years. Telbivudine (LdT) is now more commonly used in place of lamivudine but is ineffective against 3TC-resistant HBV. Genotyping and identification of resistanceassociated substitutions (RAS) is not practical in many locations.

OBJECTIVES

A novel assay was designed to enable HBV genotyping and characterisation of resistance mutations directly from serum samples stored on filter paper, using Sanger and MinION sequencing.

STUDY DESIGN

The assay was applied to a cohort of 30 samples stored on filter paper for several years with HBV viral loads ranging from 8.2 × 10⁸ to 635 IU/mL. A set of 6 high-titre samples were used in a proof-of-principle study using the MinION sequencer.

RESULTS

The assay allowed determination of HBV genotype and elucidation of RAS down to 600 IU/mL using a 550bp amplicon. Sequencing of a 1.2 kb amplicon using a MinION sequencer gave results consistent with Sanger sequencing and allowed the identification of minor populations of variants.

CONCLUSIONS

We present two approaches for reliable HBV sequencing and RAS identification using methods suitable for resource-limited environments. This is the first demonstration of extraction-free DNA sequencing direct from DSS using MinION and these workflows are adaptable to the investigation of other DNA viruses.

Human Bocavirus infection and respiratory tract disease identified in a UK patient cohort

•

Human Bocavirus 1 (HBoV1) was commonly detected in a survey of circa 13,000 UK respiratory samples between 2015 and 2019.

•

Co-infection with other viruses was observed in approximately three quarters of samples.

•

However, mono-infection was also prevalent, and associated with clinically relevant disease.

•

Intensive care was required in 31% of HBoV1 mono-infections and ventilation in 17%.

•

Fatal multi-organ failure was observed in an apparently HBoV1 mono-infected and otherwise healthy child.

Background

Since its first isolation in 2005, Human Bocavirus (HBoV) has been repeatedly associated with acute respiratory tract infections, although its role in pathogenicity remains unclear due to high co-infection rates.

Objectives

To assess HBoV prevalence and associated disease in a cohort of respiratory patients in the East Midlands, UK between 2015 and 2019.

Study design

We initially investigated the undiagnosed burden of HBoV in a retrospective paediatric cohort sampled between 2015 and 2017 using an in-house PCR assay. HBoV was subsequently incorporated into the standard respiratory diagnostic pathway and we audited a calendar year of HBoV positive results between 2018 and 2019.

Results

Our retrospective PCR screening of previously routine diagnostic-negative samples from juvenile patients identified a 9% (n = 30) prevalence of HBoV type 1. These apparent HBoV1 mono-infections were frequently associated with respiratory tract symptoms, often severe requiring ventilation, oxygen and steroid intervention with 31% (n = 9) of individuals requiring intensive care. When HBoV screening was subsequently adopted into the routine respiratory diagnostic pathway, year-round infections were observed in both children and adults peaking in February. 185 of 9098 (2.03%) individuals were found to be HBoV positive with children aged 12–24 months the principally infected group. However, HBoV infection was also observed in patients aged over 60, predominantly as a mono-infection. 23% of the 185 unique patients were HBoV monoinfected and persistent low-level DNA positivity was observed in 15 individuals up to 6-months after initial presentation.

Conclusion

HBoV1 is a prevalent respiratory infection in the UK capable of causing serious monoinfections.

Consensus recommendations for resistance testing in the management of chronic hepatitis C virus infection: Public Health England HCV Resistance Group

The treatment of hepatitis C virus (HCV) infection has been revolutionised by the advent of oral, well-tolerated, direct acting antiviral therapies (DAA), with high cure rates. However, in some scenarios, HCV resistance to antiviral therapies may have an impact on treatment success. Public Health England's HCV Resistance Group was established to support clinicians treating people with HCV, where the issue of resistance may be a factor in clinical decision-making, and this review includes the Group's current recommendations on the use of HCV resistance testing. The authors describe the principles behind and approach to HCV resistance testing and consider evidence from in vitro studies, clinical trials and real world cohorts on the impact of HCV resistance on treatment outcomes for particular DAA regimens. Five scenarios are identified in the UK and similar settings, where, in the Group's opinion, resistance testing should be performed.

Interferon lambda 4 impacts the genetic diversity of hepatitis C virus

Hepatitis C virus (HCV) is a highly variable pathogen that frequently establishes chronic infection. This genetic variability is affected by the adaptive immune response but the contribution of other host factors is unclear. Here, we examined the role played by interferon lambda-4 (IFN-λ4) on HCV diversity; IFN-λ4 plays a crucial role in spontaneous clearance or establishment of chronicity following acute infection. We performed viral genome-wide association studies using human and viral data from 485 patients of white ancestry infected with HCV genotype 3a. We demonstrate that combinations of host genetic variants, which determine IFN-λ4 protein production and activity, influence amino acid variation across the viral polyprotein - not restricted to specific viral proteins or HLA restricted epitopes - and modulate viral load. We also observed an association with viral di-nucleotide proportions. These results support a direct role for IFN-λ4 in exerting selective pressure across the viral genome, possibly by a novel mechanism.

Impact of IFNL4 Genetic Variants on Sustained Virologic Response and Viremia in Hepatitis C Virus Genotype 3 Patients

Hepatitis C virus (HCV) genotype 3 is very prevalent in Europe and Asia and is associated with worst outcomes than other genotypes. Genetic factors have been associated with HCV infection; however, no extensive genome-wide study has been performed among HCV genotype 3 patients. In this study, using a large cohort of 1,759 patients infected with HCV genotype 3, we explore the role of genetic variants on the response to interferon (IFN) and direct-acting antiviral (DAA) regimens and viremia in a combined candidate gene and genome-wide analysis. We show that genetic variants within the IFN lambda 4 (IFNL4) locus are the major factors associated with the studied traits, accordingly with observations in other HCV genotypes and with comparable effect sizes. In particular, the functional dinucleotide polymorphism rs368234815 was associated with IFN-based sustained virologic response (SVR) [odds ratio (OR) = 1.5, P = 2.3 × 10⁻⁷], viremia (beta = −0.23, P = 8.8 × 10⁻¹⁰), and also DAA-based SVR (OR = 1.7; P = 4.2 × 10⁻⁴). Our results provide evidence for a role of genetic variants on HCV viremia and SVR, notably DAA-based, in patients infected with HCV genotype 3.

The association between hepatocellular carcinoma and direct-acting anti-viral treatment in patients with decompensated cirrhosis

BACKGROUND

Direct-acting anti-viral therapy (DAA) has transformed hepatitis C virus (HCV) care, particularly in patients with decompensated cirrhosis. However, their impact on hepatocellular carcinoma (HCC) remains unclear.

AIM

To use a national registry of patients with advanced liver disease to explore the relationship between DAA therapy and HCC.

METHODS

All patients with de novo HCC post DAA therapy were frequency matched with patients who did not develop HCC. Demographic, clinical and laboratory data were obtained. Cross-sectional imaging and multidisciplinary team reports were reviewed for dates of HCC diagnosis and HCC progression. Patients were categorised by treatment outcome and time of HCC development. Data were examined by multivariable analysis and Kaplan-Meier estimation.

RESULTS

Eighty patients with HCC were compared with 165 patients without HCC, treated between June 2014 and September 2015. Mean follow-up from start of DAA therapy was 32.4 months. Twenty-eight patients were diagnosed with early HCC (within 6 months of therapy) and 52 presented late. Baseline nonmalignant lesions (HR: 1.99), thrombocytopaenia (HR: 1.59) and diabetes (HR: 1.68) increased likelihood of HCC. Response to therapy was reduced in patients who developed liver cancer (SVR in patients with HCC = 54/80 (68%), SVR in patients without HCC = 143/165 (87%), P < 0.001, OR: 3.13, 95% CI: 1.64-5.99). We found no difference between tumour size, progression or survival between viraemic and nonviraemic patients.

CONCLUSION

There is no alteration in prognosis or cancer progression following HCC development after HCV treatment. However, baseline nonmalignant liver lesions, diabetes and thrombocytopaenia increase the risk of HCC, and HCC is associated with a decreased SVR rate.

Testing for hepatitis C virus infection in UK prisons: What actually happens?

Prisons are a key demographic in the drive to eradicate hepatitis C virus (HCV) as a major public health threat. We have assessed the impact of the recently introduced national opt-out policy on the current status of HCV testing in 14 prisons in the East Midlands (UK). We analysed testing rates pre- and post-introduction of opt-out testing, together with face-to-face interviews with prison healthcare and management staff in each prison. In the year pre-opt-out, 1972 people in prison (PIP) were tested, compared to 3440 in the year following opt-out. From July 2016 to June 2017, 2706 people were tested, representing 13.5% of all prison entrants (median 16.6%, range 7.6%-40.7%). Factors correlating with testing rates were as follows: pre-admission location of the PIP (another prison or the community, OR 2.2, 95% CI 1.9-2.3, P < 0.001); whether the PIP could access health care independently of prison officers (OR 1.7, 95% CI 1.5-1.8, P < 0.001); the absence of out-reach services for HCV treatment (OR 1.3, 95% CI 1.2-1.5, P < 0.001), whether >50% of PIP reported ease of access to a nurse (OR 2.0, 95% CI 1.8-2.2, P < 0.001), and whether prison health care was supplied by private or NHS providers (OR 1.3, 95% CI 1.2-1.5, P < 0.001). Testing rates remained far below the minimum national opt-out target of 50%. Inadequacy of healthcare facilities and constraints imposed by adherence to prison regimens were cited by healthcare and management staff at all prisons. Without radical change, the prison estate may be intrinsically incapable of supporting NHSE to deliver the HCV elimination strategy.

The Hepatitis C Awareness Through to Treatment (HepCATT) study: improving the cascade of care for hepatitis C virus-infected people who inject drugs in England

BACKGROUND AND AIMS

Previous studies have shown low rates of diagnosis and treatment of hepatitis C virus (HCV) infection in people who inject drugs (PWID). Our aims were to test the effect of a complex intervention [Hepatitis C Awareness Through to Treatment (HepCATT)] in drug and alcohol clinics-primarily, on engagement of HCV-positive PWID with therapy and, secondarily, on testing for HCV, referral to hepatology services and start of HCV treatment.

DESIGN AND SETTING

A non-randomized pilot study in three specialist addiction clinics in England comparing an intervention year (starting between September 2015 and February 2016) with a baseline year (2014), together with three control clinics.

PARTICIPANTS

Analysis included all attendees at the intervention and control specialist addiction clinics identified as PWID.

INTERVENTION

The intervention comprised the placement of a half-time facilitator in each clinic for 12 months with the brief to increase diagnosis of HCV infection within clients at those services and the engagement of diagnosed individuals with an appropriate care pathway. The facilitator undertook various activities, which could include training of key workers, direct interaction with clients, streamlining and support for hepatology appointments and introduction of dried blood-spot testing.

MEASUREMENTS

For each clinic and period, we obtained the total number of clients and, as relevant, their status as PWID, tested for HCV, known HCV-positive, engaged with HCV therapy or treated.

FINDINGS

Compared with baseline, there was strong evidence that engagement with HCV therapy in the intervention year increased (P < 0.001) more in the HepCATT centres than controls, up ⁺ 31 percentage points [95% confidence interval (CI) = 19-43] versus -12 (CI = -31 to ⁺ 6) and odds ratio (OR) = 9.99 (CI = 4.42-22.6) versus 0.35 (CI = 0.08-1.56). HepCATT centres also had greater increases in HCV testing (OR = 3.06 versus 0.78, P < 0.001), referral to hepatology (OR = 9.60 versus 0.56, P < 0.001) and treatment initiation (OR = 9.5 versus 0.74, P < 0.001).

CONCLUSIONS

Introducing a half-time facilitator into drug and alcohol clinics in England increased engagement of HCV-positive people who inject drugs with hepatitis C virus care pathways, with increased uptake also of testing, referral to hepatology and initiation of treatment.

Trichodysplasia Spinulosa Polyomavirus in Respiratory Tract of Immunocompromised Child

Trichodysplasia spinulosa polyomavirus causes trichodysplasia spinulosa, a skin infection, in immunocompromised persons, but the virus is rarely detected in respiratory samples. Using PCR, we detected persistent virus in respiratory and skin samples from an immunocompromised boy with respiratory signs but no characteristic skin spicules. This virus may play a role in respiratory illness.

Elevated serum activity of MBL and ficolin-2 as biomarkers for progression to hepatocellular carcinoma in chronic HCV infection

Hepatocellular carcinoma (HCC) is an uncommon but significant outcome of chronic hepatitis C virus (HCV) infection. A serum biomarker for predicting progression to HCC would have a major impact on patient monitoring and clinical management. We explored circulating liver-expressed lectins, ficolin-2, ficolin-3 and mannose binding lectin (MBL), as potential biomarkers for the development of HCC. The activity of these three lectins were analysed in HCV positive patients who developed HCC (n = 31) with comparable HCV-positive HCC-negative patients (n = 106) and healthy controls (n = 79). Serum binding activity of ficolin-2 and MBL were elevated compared to controls. Analysis of pre-HCC onset samples revealed that MBL levels were significantly elevated up to 3 years, and ficolin-2 was elevated up to 1 year, prior to diagnosis of HCC over controls. This preliminary study identifies MBL and ficolin-2 as potential biomarkers for the development of HCC in chronic HCV infection.

Expression of human ficolin-2 in hepatocytes confers resistance to infection by diverse hepatotropic viruses

The liver-expressed pattern recognition receptors mannose-binding lectin (MBL), ficolin-2 and ficolin-3 contribute to the innate immune response by activating complement. Binding of soluble ficolin-2 to viral pathogens can directly neutralize virus entry. We observed that the human hepatoma cell line HuH7.5, which is routinely used for the study of hepatotropic viruses, is deficient in expression of MBL, ficolin-2 and ficolin-3. We generated a cell line that expressed and secreted ficolin-2. This cell line (HuH7.5 [FCN2]) was more resistant to infection with hepatitis C virus (HCV), ebolavirus and vesicular stomatitis virus, but surprisingly was more susceptible to infection with rabies virus. Cell-to-cell spread of HCV was also inhibited in ficolin-2 expressing cells. This illustrates that ficolin-2 expression in hepatocytes contributes to innate resistance to virus infection, but some viruses might utilize ficolin-2 to facilitate entry.

Epidemiology and natural history of hepatitis C virus infection among children and young people

BACKGROUND & AIMS

Chronic hepatitis C virus (HCV) infection is a global health burden. Although HCV infection rarely contributes to morbidity during childhood, most HCV-infected children develop chronic HCV with a lifetime risk of liver disease. Little is known about the development of long-term liver disease and the effect of treatment in patients infected with HCV in childhood.

METHOD

This study was a retrospective review of patients infected with HCV in childhood enrolled in HCV Research UK. A total of 1,049 patients were identified and included.

RESULTS

The main routes of infection were intravenous drug use (53%), blood product exposure (24%) and perinatal infection (11%). Liver disease developed in 32% of patients, a median of 33 years after infection, irrespective of the mode of infection. Therefore, patients with perinatal exposure developed cirrhosis at an earlier age than the rest of the risk groups. The incidence of hepatocellular carcinoma (HCC) was 5%, liver transplant 4% and death occurred in 3%. Overall, 663 patients were treated (55% with interferon/pegylated interferon and 40% with direct-acting antivirals). Sustained virological response (SVR) was achieved in 406 (75%). There was a higher mortality rate among patients without SVR vs. those with SVR (5% vs. 1%, p = 0.003). Treatment was more effective in patients without cirrhosis and disease progression was less frequent (13%) than in patients with cirrhosis at the time of therapy (28%) p < 0.001. Patients with cirrhosis were more likely to develop HCC, require liver transplantation, or die.

CONCLUSION

HCV infection in young people causes significant liver disease, which can now be prevented with antiviral therapy. Early treatment, especially before development of cirrhosis is essential. Detection of HCV should be aimed at relevant risk groups and antiviral therapy should be made available in childhood to prevent long-term liver disease and spread of HCV.

LAY SUMMARY

Chronic hepatitis C virus (HCV) infection is a global health problem, which can now be treated with potent direct-acting antiviral drugs. This study demonstrates that HCV infection in childhood causes serious liver disease in 32% of patients, a median of 33 years after infection, irrespective of age, mode and route of infection. Disease outcomes were better in patients treated before the development of advanced liver disease. Antiviral therapy should be made available in childhood to prevent long-term liver disease and the spread of HCV.

Short-term changes observed in multiparametric liver MRI following therapy with direct-acting antivirals in chronic hepatitis C virus patients

Methods

We applied multiparametric MRI to assess changes in liver composition, perfusion and blood flow in 17 patients before direct-acting antiviral (DAA) therapy and after treatment completion (within 12 weeks of last DAA tablet swallowed).

Results

We observed changes in hepatic composition indicated by a reduction in both liver longitudinal relaxation time (T1, 35 ± 4 ms), transverse relaxation time (T2, 2.5 ± 0.8 ms; T2* 3.0 ± 0.7 ms), and liver perfusion (28.1 ± 19.7 ml/100 g/min) which we suggest are linked to reduced pro-inflammatory milieu, including interstitial oedema, within the liver. No changes were observed in liver or spleen blood flow, splenic perfusion, or superior mesenteric artery blood flow.

Conclusion

For the first time, our study has shown that treatment of HCV with DAAs in patients with cirrhosis leads to an acute reduction in liver T1, T2 and T2* and an increase in liver perfusion measured using MR parameters. The ability of MRI to characterise changes in the angio-architecture of patients with cirrhosis after intervention in the short term will enhance our understanding of the natural history of regression of liver disease and potentially influence clinical decision algorithms.

Key Points

• DAAs have revolutionised the treatment of hepatitis C and achieve sustained virological response in over 95% of patients, even with liver cirrhosis.

• Currently available non-invasive measures of liver fibrosis are not accurate after HCV treatment with DAAs, this prospective single-centre study has shown that MRI can sensitively measure changes within the liver, which could reflect the reduction in inflammation with viral clearance.

• The ability of MRI to characterise changes in structural and haemodynamic MRI measures in the liver after intervention will enhance our understanding of the progression/regression of liver disease and could potentially influence clinical decision algorithms.

SOX9 predicts progression toward cirrhosis in patients while its loss protects against liver fibrosis

Fibrosis and organ failure is a common endpoint for many chronic liver diseases. Much is known about the upstream inflammatory mechanisms provoking fibrosis and downstream potential for tissue remodeling. However, less is known about the transcriptional regulation in vivo governing fibrotic matrix deposition by liver myofibroblasts. This gap in understanding has hampered molecular predictions of disease severity and clinical progression and restricted targets for antifibrotic drug development. In this study, we show the prevalence of SOX9 in biopsies from patients with chronic liver disease correlated with fibrosis severity and accurately predicted disease progression toward cirrhosis. Inactivation of Sox9 in mice protected against both parenchymal and biliary fibrosis, and improved liver function and ameliorated chronic inflammation. SOX9 was downstream of mechanosignaling factor, YAP1. These data demonstrate a role for SOX9 in liver fibrosis and open the way for the transcription factor and its dependent pathways as new diagnostic, prognostic, and therapeutic targets in patients with liver fibrosis.

Comorbidities and medications of patients with chronic hepatitis C under specialist care in the UK

Designing services with the capacity and expertise to meet the needs of the chronic hepatitis C (CHC) population in the era of direct acting antivirals (DAAs), and widening access to such treatments, requires detailed understanding of the characteristics and healthcare needs of the existing patient population. In this retrospective analysis of data from the National HCV Research UK Biobank between March 2012 and October 2014, the characteristics of the CHC population currently under specialist care in the UK were evaluated—with specific focus upon use of medications, adverse lifestyle choices, and comorbidities. Demographic data, risk factors for CHC acquisition, HCV genotype, liver disease status, lifestyle factors, comorbidities, and medication classes were collected. Data were analyzed by history of injecting drug use (IDU), age, and severity of liver disease. A total of 6278 patients (70.5% white; median age, 52 years) from 59 UK specialist centres were included; 59.1% of patients had acquired HCV through IDU. The prevalence of adverse lifestyle factors was significantly lower in non‐IDU compared with previous IDU or recent IDU patients. Depression was common in the previous (50.8%) and recent IDU (68.1%) groups, compared with 27.6% in non‐IDU patients. Cirrhosis was common (23.6%), and prevalence increased with age. We describe a heterogeneous, polymorbid, and aging population of CHC patients in secondary care, and demonstrate underrepresentation of injecting drug users within the current system. The implications of this present significant challenges to physicians and healthcare commissioners in designing services which are fit for purpose inthe DAA era.

IFN-λ3, not IFN-λ4, likely mediates IFNL3-IFNL4 haplotype-dependent hepatic inflammation and fibrosis

Genetic variation in the IFNL3-IFNL4 (interferon-λ3-interferon-λ4) region is associated with hepatic inflammation and fibrosis. Whether IFN-λ3 or IFN-λ4 protein drives this association is not known. We demonstrate that hepatic inflammation, fibrosis stage, fibrosis progression rate, hepatic infiltration of immune cells, IFN-λ3 expression, and serum sCD163 levels (a marker of activated macrophages) are greater in individuals with the IFNL3-IFNL4 risk haplotype that does not produce IFN-λ4, but produces IFN-λ3. No difference in these features was observed according to genotype at rs117648444, which encodes a substitution at position 70 of the IFN-λ4 protein and reduces IFN-λ4 activity, or between patients encoding functionally defective IFN-λ4 (IFN-λ4-Ser70) and those encoding fully active IFN-λ4-Pro70. The two proposed functional variants (rs368234815 and rs4803217) were not superior to the discovery SNP rs12979860 with respect to liver inflammation or fibrosis phenotype. IFN-λ3 rather than IFN-λ4 likely mediates IFNL3-IFNL4 haplotype-dependent hepatic inflammation and fibrosis.

Outcomes after successful direct-acting antiviral therapy for patients with chronic hepatitis C and decompensated cirrhosis

BACKGROUND & AIMS

Direct-acting antivirals have become widely used for patients with chronic hepatitis C virus infection with decompensated cirrhosis. Virological responses are excellent and early improvements in liver function, at least in a proportion of patients, have been observed but the longer term impact of viral clearance on end-stage liver disease complications is unclear.

METHODS

Prospective study of patients with decompensated cirrhosis who received 12weeks of all-oral direct-acting antivirals through the English Expanded Access Programme. Endpoints were deaths, liver transplantation, hepatocellular carcinoma, serious decompensation events, sepsis or hospitalisations, and MELD scores between start of therapy to 15months post-treatment start. An untreated cohort of patients was retrospectively studied over 6months for comparison.

RESULTS

Amongst 317/406 patients who achieved sustained virological response at 24weeks post-treatment, there were 9 deaths (3%), 17 new liver cancers (5%), 39 transplantations (12%) and 52 with serious decompensations (16%), over 15months. When compared to the first six months from treatment start and to untreated patients, there was a reduction in incidence of decompensations [30/406 (7%) in months 6-15 and 72/406 (18%) in months 0-6 for treated patients vs. 73/261 (28%) in untreated patients]. There was no significant difference in liver cancer incidence (10/406 (2.5%) in months 6-15 and 17/406 (4%) in months 0-6 for treated patients vs. 11/261 (4%) in untreated patients).

CONCLUSIONS

This study suggests that antiviral therapy in patients with decompensated cirrhosis led to prolonged improvement in liver function, with no evidence of paradoxical adverse impact nor increase in liver malignancy.

LAY SUMMARY

This is a report of a large group of patients in England who have hepatitis C virus (HCV) infection with advanced liver disease. They have been treated with new anti-HCV drugs, which cured the infection in the majority. This study looks at their outcomes a year following treatment, in terms of deaths, cancers and other complications of advanced liver disease. We conclude that in most patients anti-HCV treatment is beneficial even in advanced liver disease.

Diverse impacts of the rs58542926 E167K variant in TM6SF2 on viral and metabolic liver disease phenotypes

A genome-wide exome association study has identified the transmembrane 6 superfamily member 2 (TM6SF2) rs58542926 variant encoding an E167K substitution as a genetic determinant of hepatic steatosis in nonalcoholic fatty liver disease (NAFLD). The roles of this variant across a spectrum of liver diseases and pathologies and on serum lipids comparing viral hepatitis to NAFLD and viral load in chronic viral hepatitis, as well as its intrahepatic molecular signature, have not been well characterized. We undertook detailed analyses in 3260 subjects with viral and nonviral liver diseases and in healthy controls. Serum inflammatory markers and hepatic expression of TM6SF2 and genes regulating lipid metabolism were assessed in a subset with chronic hepatitis C (CHC). The rs58542926 T allele was more prevalent in 502 NAFLD patients than controls (P = 0.02) but not different in cohorts with CHC (n = 2023) and chronic hepatitis B (n = 507). The T allele was associated with alterations in serum lipids and hepatic steatosis in all diseases and with reduced hepatic TM6SF2 and microsomal triglyceride transfer protein expression. Interestingly, the substitution was associated with reduced CHC viral load but increased hepatitis B virus DNA. The rs58542926 T allele had no effect on inflammation, impacted ≥F2 fibrosis in CHC and NAFLD assessed cross-sectionally (odds ratio = 1.39, 95% confidence interval 1.04-1.87, and odds ratio = 1.62, 95% confidence interval 1.03-2.52, respectively; P < 0.03 for both), but had no effect on fibrosis progression in 1174 patients with CHC and a known duration of infection.

CONCLUSION

The TM6SF2 E167K substitution promotes steatosis and lipid abnormalities in part by altering TM6SF2 and microsomal triglyceride transfer protein expression and differentially impacts CHC and chronic hepatitis B viral load, while effects on fibrosis are marginal. (Hepatology 2016;64:34-46).

Is increased hepatitis C virus case-finding combined with current or 8-week to 12-week direct-acting antiviral therapy cost-effective in UK prisons? A prevention benefit analysis

Prisoners have a high prevalence of hepatitis C virus (HCV), but case-finding may not have been cost-effective because treatment often exceeded average prison stay combined with a lack of continuity of care. We assessed the cost-effectiveness of increased HCV case-finding and treatment in UK prisons using short-course therapies. A dynamic HCV transmission model assesses the cost-effectiveness of doubling HCV case-finding (achieved through introducing opt-out HCV testing in UK pilot prisons) and increasing treatment in UK prisons compared to status quo voluntary risk-based testing (6% prison entrants/year), using currently recommended therapies (8-24 weeks) or interferon (IFN)-free direct-acting antivirals (DAAs; 8-12 weeks, 95% sustained virological response, £3300/week). Costs (British pounds, £) and health utilities (quality-adjusted life years) were used to calculate mean incremental cost-effectiveness ratios (ICERs). We assumed 56% referral and 2.5%/25% of referred people who inject drugs (PWID)/ex-PWID treated within 2 months of diagnosis in prison. PWID and ex-PWID or non-PWID are in prison an average 4 and 8 months, respectively. Doubling prison testing rates with existing treatments produces a mean ICER of £19,850/quality-adjusted life years gained compared to current testing/treatment and is 45% likely to be cost-effective under a £20,000 willingness-to-pay threshold. Switching to 8-week to 12-week IFN-free DAAs in prisons could increase cost-effectiveness (ICER £15,090/quality-adjusted life years gained). Excluding prevention benefit decreases cost-effectiveness. If >10% referred PWID are treated in prison (2.5% base case), either treatment could be highly cost-effective (ICER<£13,000). HCV case-finding and IFN-free DAAs could be highly cost-effective if DAA cost is 10% lower or with 8 weeks' duration.

CONCLUSIONS

Increased HCV testing in UK prisons (such as through opt-out testing) is borderline cost-effective compared to status quo voluntary risk-based testing under a £20,000 willingness to pay with current treatments but likely to be cost-effective if short-course IFN-free DAAs are used and could be highly cost-effective if PWID treatment rates were increased. (Hepatology 2016;63:1796-1808).