A Territorywide Prevalence Study on Blood-Borne and Enteric Viral Hepatitis in Hong Kong

Adjusted estimate of the prevalence of hepatitis delta virus in 25 countries and territories

BACKGROUND & AIMS

Hepatitis delta virus (HDV) is a satellite RNA virus that requires the hepatitis B virus (HBV) for assembly and propagation. Individuals infected with HDV progress to advanced liver disease faster than HBV-monoinfected individuals. Recent studies have estimated the global prevalence of anti-HDV antibodies among the HBV-infected population to be 5-15%. This study aimed to better understand HDV prevalence at the population level in 25 countries/territories.

METHODS

We conducted a literature review to determine the prevalence of anti-HDV and HDV RNA in hepatitis B surface antigen (HBsAg)-positive individuals in 25 countries/territories. Virtual meetings were held with experts from each setting to discuss the findings and collect unpublished data. Data were weighted for patient segments and regional heterogeneity to estimate the prevalence in the HBV-infected population. The findings were then combined with The Polaris Observatory HBV data to estimate the anti-HDV and HDV RNA prevalence in each country/territory at the population level.

RESULTS

After adjusting for geographical distribution, disease stage and special populations, the anti-HDV prevalence among the HBsAg+ population changed from the literature estimate in 19 countries. The highest anti-HDV prevalence was 60.1% in Mongolia. Once adjusted for the size of the HBsAg+ population and HDV RNA positivity rate, China had the highest absolute number of HDV RNA+ cases.

CONCLUSIONS

We found substantially lower HDV prevalence than previously reported, as prior meta-analyses primarily focused on studies conducted in groups/regions that have a higher probability of HBV infection: tertiary care centers, specific risk groups or geographical regions. There is large uncertainty in HDV prevalence estimates. The implementation of reflex testing would improve estimates, while also allowing earlier linkage to care for HDV RNA+ individuals. The logistical and economic burden of reflex testing on the health system would be limited, as only HBsAg+ cases would be screened.

IMPACT AND IMPLICATIONS

There is a great deal of uncertainty surrounding the prevalence of hepatitis delta virus among people living with hepatitis B virus at the population level. In this study, we aimed to better understand the burden in 25 countries and territories, to refine techniques that can be used in future analyses. We found a lower prevalence in the majority of places studied than had been previously reported. These data can help inform policy makers on the need to screen people living with hepatitis B virus to find those coinfected with hepatitis delta virus and at high risk of progression, while also highlighting the pitfalls that other researchers have often fallen into.

Changing prevalence of chronic hepatitis B virus infection in China between 1973 and 2021: a systematic literature review and meta-analysis of 3740 studies and 231 million people

OBJECTIVE

China concentrates a large part of the global burden of HBV infection, playing a pivotal role in achieving the WHO 2030 global hepatitis elimination target.

METHODS

We searched for studies reporting HBV surface antigen (HBsAg) seroprevalence in five databases until January 2023. Eligible data were pooled using a generalised linear mixed model with random effects to obtain summary HBsAg seroprevalence. Linear regression was used to estimate annual percentage change (APC) and HBsAg prevalence in 2021.

RESULTS

3740 studies, including 231 million subjects, were meta-analysed. HBsAg seroprevalence for the general population decreased from 9.6% (95% CI 8.4 to 10.9%) in 1973-1984 to 3.0% (95% CI 2.1 to 3.9%) in 2021 (APC=-3.77; p<0.0001). Decreases were more pronounced in children <5 years (APC=-7.72; p<0.0001) and 5-18 years (-7.58; p<0.0001), than in people aged 19-59 years (-2.44; p<0.0001), whereas HBsAg seroprevalence increased in persons ≥60 years (2.84; p=0.0007). Significant decreases were observed in all six major Chinese regions, in both men (APC=-3.90; p<0.0001) and women (-1.82; p<0.0001) and in high-risk populations. An estimated 43.3 million (95% uncertainty interval 30.7-55.9) persons remained infected with HBV in China in 2021 (3.0%), with notable heterogeneity by region (<1.5% in North China to>6% in Taiwan and Hong Kong) and age (0.3%, 1.0%, 4.7% and 5.6% for <5 years, 5-18 years, 19-59 years and ≥60 years, respectively).

CONCLUSIONS

China has experienced remarkable decreases in HBV infection over the last four decades, but variations in HBsAg prevalence persist in subpopulations. Ongoing prevention of HBV transmission is needed to meet HBV elimination targets by 2030.

TRIAL REGISTRATION NUMBER

PROSPERO (CRD42021284217).

Trends and future projections of liver cancer incidence in Hong Kong: a population-based study

BACKGROUND

Liver cancer remains a significant burden in Hong Kong. We sought to examine trends in liver cancer incidence using 30 years of cancer registry data in Hong Kong. Additionally, we aimed to assess the impact of age, period and birth cohort on liver cancer incidence, provided projections for liver cancer incidence until 2030, and examined the drivers of liver cancer incidence.

METHODS

Data on liver cancer incidence were collected from the Hong Kong Cancer Registry (HKCaR). We assessed age, period, and birth cohort effects using age-period-cohort (APC) models. We employed Bayesian APC analysis with integrated nested Laplace approximations to project the future burden of liver cancer in Hong Kong. Furthermore, we attributed the changes in new liver cancer cases to population growth, population ageing, and epidemiological changes.

RESULTS

The study included a total of 51,333 individuals, of whom 39,287 (76.53%) were male. From 1991 to 2020, the age-standardized liver cancer incidence rate in Hong Kong continued declining, while the number of new cases increased significantly, especially among males. The net drift, representing the overall annual percentage change of the age-adjusted rate, was - 3.06% (95% confidence interval [CI]: -3.31% to -2.80%) for males and - 3.85% (95% CI: -4.61% to -3.09%) for females. Local drift, which estimates the annual percentage change over time specific to age group, decreased in all age groups for both sexes, with a more pronounced decrease in younger age groups. The period and cohort risk of developing liver cancer also showed decreasing trends for both sexes. The study projected a decline in liver cancer cases for males but an increase for females in Hong Kong, with an estimated 1,083 cases in males and 710 cases in females by 2030. Demographic decomposition analysis revealed that while population growth and ageing were the main drivers of increased liver cancer cases, epidemiologic shifts mostly offset these factors.

CONCLUSION

The period and cohort risk of developing liver cancer in Hong Kong declined due to epidemiological changes. Although the age-standardized incidence rates of liver cancer have also declined, demographic and epidemiological factors have led to lower case expectations in males but a likely increase in females. Further research and epidemiological assessment of the disease are needed.

A longitudinal study to detect hepatitis B surface and core-related antigens in chronic hepatitis B patients with hepatitis B surface antigen seroclearance using highly sensitive assays

BACKGROUND

This study aimed to evaluate the usefulness of two novel assays, namely the iTACT-hepatitis B surface antigen (iTACT-HBsAg) and iTACT-hepatitis B core-related antigen (iTACT-HBcrAg) assays, in chronic hepatitis B (CHB) patients with HBsAg seroclearance (SC) documented by standard assays.

METHODS

HBsAg and HBcrAg were measured by the two iTACT-assays in 556 serial sera collected from 96 CHB patients at 7 different time points spanning from 5 years before to 10 years after SC and 120 HBsAg-negative, anti-HBc-positive individuals. As controls, 60 seronegative individuals, who were negative for HBsAg, anti-HBc and anti-HBs, were tested.

RESULTS

Using the iTACT-assays, HBsAg was detectable in 154/418 (36.8%) samples collected after SC. HBcrAg was detectable in 78.3% and 65.9% of samples collected before and after SC, respectively. The detectability rates of both HBsAg and HBcrAg progressively decreased over time after SC. At 10 years after SC, 20.4% and 64.5% of the patients still had detectable HBsAg and HBcrAg, respectively. 66 (71%) patients had detectable HBsAg and/or HBcrAg. Among the 120 HBsAg-negative, anti-HBc-positive individuals, 11 (9.2%) and 4 (3.3%) had detectable HBsAg and HBcrAg respectively. Both HBsAg and HBcrAg were undetectable in the controls.

CONCLUSION

The iTACT assays detected a low level of HBsAg and/or HBcrAg in >70% of patients even at 10 years after SC, suggesting that CHB patients with SC still harbour a low level of HBV protein expression. The clinical significance of detectable viral proteins after SC with regard to disease progression and HBV reactivation deserves further investigations.

Risk of alanine aminotransferase flare in patients with previous hepatitis B virus exposure on biological modifier therapies-A population-based study

BACKGROUND

It is uncertain whether biological therapies would increase the risk of hepatitis among patients with past hepatitis B virus (HBV) infection. This study aimed to evaluate the risk of alanine aminotransferase (ALT) flare in patients with past HBV infection while using biological therapies.

METHODOLOGY

Patients who received biological therapies for ≥3 months from 2000 to 2019 were identified from a population-based database in Hong Kong. Patients with past HBV infection were compared with a control group without prior HBV exposure. The primary endpoint was development of ALT flare within 5 years of starting biological therapies, defined as ALT >80 IU/L.

RESULTS

There were 2471 and 2394 patients with and without past HBV infection respectively. There was a non-significant increase in risk of ALT flare among the HBV-exposed group (27.6% vs. 23.7%, p = .055). In multivariable analysis, using prednisolone-equivalent dose of >20 mg daily, male sex and concomitant immunosuppressants were risk factors for ALT flare. The risk of ALT flare was significantly higher with anti-CD20 when compared to other biological agents (36.1% vs. 14.5%, p < .01), but was not significantly different among anti-tumour necrosis factor, anti-cytokine, Janus kinase inhibitors and T cell/B cell inhibitors or anti-integrin (15.2% vs. 14.6% vs. 11.7% vs. 11.1%, p = .82). Among patients with documented hepatitis B surface antigen seroreversion, 96% were on anti-CD20.

CONCLUSIONS

Our study further supports the current suggestion of prophylactic anti-viral before starting anti-CD20 in HBV-exposed patients. While other biological therapies appear to have a lower risk for ALT flare, this result needs further confirmation.

Hepatitis B burden and population immunity in a high endemicity city - a geographically random household epidemiology study for evaluating achievability of elimination

This study aimed to provide reference for evaluating the achievability of hepatitis B virus (HBV) elimination in a high endemicity city with universal neonatal vaccination in place for over 30 years. Between September 2018 and October 2020, 2085 citizens from 1143 geographically random households in Hong Kong completed a questionnaire and had blood-testing for HBV markers (anti-HBs, HBsAg, anti-HBc, HBeAg). We evaluated the epidemiology and examined factors associated with HBV exposure, vaccination and chronic diseases. The proportion of households with HBsAg positive index participants was 9.2% (95% CI 7.5%-10.9%). The age- and sex-adjusted HBsAg prevalence was 6.3% (95% CI 5.3%-7.4%), compared to >10% in those born in 1960-1970 and among non-local born citizens, and <1% in people born after introduction of neonatal vaccination. Among 155 HBsAg positive participants, 59% were aware of their infection status with 10% on treatment and 10/150 (6.7%) HBeAg positive. More than 40% (872/2064) tested negative for both HBsAg and anti-HBs, contributed by the lack of immunity in older adults and the waning immunity of vaccines. Hong Kong has remained at high-intermediate HBV endemicity state. The moderate level of anti-HBs positivity and very low treatment coverage (10%) among HBsAg positive participants pose challenges for achieving the HBV elimination target.

Systematic Review of Hepatitis C Virus Prevalence in the WHO Western Pacific Region

BACKGROUND

This review aimed to identify hepatitis C virus (HCV) prevalence estimates among the general population and six key populations (people who inject drugs, men who have sex with men, sex workers, prisoners/detainees, Indigenous people, and migrants) in the World Health Organization Western Pacific Region (WHO WPR).

METHODS

Original research articles published between 2016 and 2020 were identified from bibliographic databases. Publications were retrieved, replicas removed, and abstracts screened. Retained full texts were assessed and excluded if inclusion criteria were not met. Methodological quality was assessed using the Johanna Briggs Institute critical appraisal checklist for prevalence data. Data on HCV exposure and active infection were extracted and aggregated and forest plots generated for each population by country.

RESULTS

There were no HCV prevalence estimates in any population for more than half of WPR countries and territories. Among the 76 estimates, 97% presented prevalence of exposure and 33% prevalence of active infection. General population viraemic prevalence was 1% or less, except in Mongolia. Results confirm the endemic nature of HCV among people who inject drugs, with estimates of exposure ranging from 30% in Cambodia to 76% in Hong Kong.

CONCLUSIONS

Countries require detailed knowledge of HCV prevalence in diverse populations to evaluate the impact of efforts to support WHO HCV elimination goals. Results provide baseline estimates from which to monitor and evaluate progress and by which to benchmark future elimination efforts.

Clinical trial: intra dermal hepatitis B vaccination with topical imiquimod versus intra muscular hepatitis B vaccination in patients with inflammatory bowel disease

BACKGROUND

Efficacy with conventional intra muscular (IM) hepatitis B vaccination in patients with inflammatory bowel disease (IBD) is suboptimal.

AIM

To compare the immunogenicity of intradermal (ID) hepatitis B vaccination after topical imiquimod pre-treatment with IM hepatitis B vaccination in patients with IBD.

METHODS

Adult IBD patients with no evidence of hepatitis B infection or immunity (negative to HBsAg/anti-HBc/anti-HBs) were randomised 1:1 to receive either ID hepatitis B vaccine with topical imiquimod pre-treatment to injection site (ID-Imq) or IM hepatitis B vaccine with aqueous cream pre-treatment (IM-Aq) at 0, 1 and 6 months. Patients and investigators were blinded to the randomisation and intervention. The primary endpoint was seroprotection rate at 12-month, defined as percentage of subjects with anti-HBs ≥10 mIU/ml.

RESULTS

Between September 2019 and December 2020, 104 patients with IBD (68% male; 50% Crohn's) enrolled, and 53 assigned to ID-Imq group. The percentage of patients using steroids, immunomodulators or biologics at randomisation was 15%, 55% or 22%, respectively. Seroprotection rate at 12 months was significantly higher in the ID-Imq group than the IM-Aq group (91% vs 69%; OR 4.39, 95% CI 1.47-13.11). Multivariate analysis showed that ID vaccine with topical imiquimod and higher albumin level were associated with a higher seroprotection rate. The safety profile was similar but local reactions were more common in the ID-Imq group.

CONCLUSIONS

Intradermal hepatitis B vaccination with topical imiquimod pre-treatment is safe and offers superior seroprotection to conventional IM administration in patients with IBD.

Detection of the hepatitis B surface antigen in patients with occult hepatitis B using an assay with enhanced sensitivity

Patients with occult hepatitis B infection (OBI) have undetectable hepatitis B surface antigen (HBsAg) by conventional assays but detectable hepatitis B virus (HBV) DNA in blood/liver. We evaluated the key performance characteristics of a sensitive HBsAg assay (ARCHITECT HBsAg Next Qualitative Assay, referred as NEXT) with respect to HBsAg detection. Assay precision, sample carryover and seroconversion sensitivity of NEXT were evaluated. HBsAg was measured by NEXT in 1,138 individuals, including 1,038 patients who attended liver clinics in a tertiary hospital (200 HBV DNA-positive blood donors whose HBsAg was undetectable by conventional assays, and 38 patients receiving immunosuppressive therapy, 800 chronic hepatitis B patients with HBsAg seroclearance) and 100 HBsAg-negative subjects recruited from a community project. The within-run and within-laboratory coefficients of variation were <6% for the positive sample pools. In 9 seroconversion panels tested, NEXT allowed an earlier HBsAg detection than conventional assays. NEXT detected HBsAg in 10/200 (5%) HBsAg-negative blood donors, 1/20 (5%) and 0/18 HBsAg-negative patients with and without HBV reactivation respectively, and 59/800 (7.3%) patients with HBsAg seroclearance. HBsAg was detectable by NEXT in 27.8%, 8.2%, 6.9%, 3.8% and 1.9% samples at <3, 3-5, >5-8, >8-11, and >11 years after HBsAg seroclearance, respectively. Seven out of 100 HBsAg-negative community identified subjects was tested positive by NEXT. Comparing with conventional HBsAg assays, NEXT demonstrated a higher sensitivity and conferred an increment of 5-7% detection rate in patients with OBI, thereby helping in identifying HBV carriers and prevention of OBI-associated HBV transmission and reactivation.

Understanding longevity in Hong Kong: a comparative study with long-living, high-income countries

BACKGROUND

Since 2013, Hong Kong has sustained the world's highest life expectancy at birth-a key indicator of population health. The reasons behind this achievement remain poorly understood but are of great relevance to both rapidly developing and high-income regions. Here, we aim to compare factors behind Hong Kong's survival advantage over long-living, high-income countries.

METHODS

Life expectancy data from 1960-2020 were obtained for 18 high-income countries in the Organisation for Economic Co-operation and Development from the Human Mortality Database and for Hong Kong from Hong Kong's Census and Statistics Department. Causes of death data from 1950-2016 were obtained from WHO's Mortality Database. We used truncated cross-sectional average length of life (TCAL) to identify the contributions to survival differences based on 263 million deaths overall. As smoking is the leading cause of premature death, we also compared smoking-attributable mortality between Hong Kong and the high-income countries.

FINDINGS

From 1979-2016, Hong Kong accumulated a substantial survival advantage over high-income countries, with a difference of 1·86 years (95% CI 1·83-1·89) for males and 2·50 years (2·47-2·53) for females. As mortality from infectious diseases declined, the main contributors to Hong Kong's survival advantage were lower mortality from cardiovascular diseases for both males (TCAL difference 1·22 years, 95% CI 1·21-1·23) and females (1·19 years, 1·18-1·21), cancer for females (0·47 years, 0·45-0·48), and transport accidents for males (0·27 years, 0·27-0·28). Among high-income populations, Hong Kong recorded the lowest cardiovascular mortality and one of the lowest cancer mortalities in women. These findings were underpinned by the lowest absolute smoking-attributable mortality in high-income regions (39·7 per 100 000 in 2016, 95% CI 34·4-45·0). Reduced smoking-attributable mortality contributed to 50·5% (0·94 years, 0·93-0·95) of Hong Kong's survival advantage over males in high-income countries and 34·8% (0·87 years, 0·87-0·88) of it in females.

INTERPRETATION

Hong Kong's leading longevity is the result of fewer diseases of poverty while suppressing the diseases of affluence. A unique combination of economic prosperity and low levels of smoking with development contributed to this achievement. As such, it offers a framework that could be replicated through deliberate policies in developing and developed populations globally.

FUNDING

Early Career Scheme (RGC ECS Grant #27602415), Research Grants Council, University Grants Committee of Hong Kong.

Achieving WHO target of HCV control in Hong Kong: challenges and strategies

With the introduction of effective directly acting antiviral agents (DAAs) therapy, control and elimination of hepatitis C virus (HCV) infection is becoming a feasible goal. In Hong Kong, HCV prevalence in general population is 0.3%-0.5% over the past decades. However, like other high-income areas/countries, high prevalence of HCV infection has been found in several population groups, such as people who inject drugs (PWID), patients undergoing dialysis, and human immunodeficiency virus infection and acquired immunodeficiency syndrome (HIV/ AIDS) patients. Based on the epidemiological study using data retrieved from the Hong Kong HCV Registry from January 2005 to March 2017, the estimated territory-wide diagnosis rate and treatment rate of HCV infection were only 50.9% and 12.4%, respectively. Although these rates was comparable to many developed countries/areas, the performances remained substantially below 90% and 80%, the 2030 targets proposed by World Health Organization (WHO). In recognition of the challenges, the Hong Kong Government set up the Steering Committee on Prevention and Control of Viral Hepatitis (SCVH) which formulated the Hong Kong Viral Hepatitis Action Plan 2020-2024. The Action Plan adopts four key strategies, as described in the WHO framework for global action, namely, awareness, surveillance, prevention and treatment. With the effective implementation of the Action Plan, especially in targeted screening of high-risk populations and more generalized use of the highly efficacious DAAs for all diagnosed HCV subjects, the goals of reducing HCV transmission and HCV-related morbidity and mortality can be achieved in Hong Kong by 2030.

Socioeconomic inequalities in treatment and relative survival among patients with diffuse large B-cell lymphoma: a Hong Kong population-based study

The influence of socioeconomic status (SES) on access to standard chemotherapy and/or monoclonal antibody therapy, and associated secular trends, relative survival, and excess mortality, among diffuse large B-cell lymphoma (DLBCL) patients is not clear. We conducted a Hong Kong population-based cohort study and identified adult patients with histologically diagnosed DLBCL between 2000 and 2018. We examined the association of SES levels with the odds and the secular trends of receipt of chemotherapy and/or rituximab. Additionally, we estimated the long-term relative survival by SES utilizing Hong Kong life tables. Among 4017 patients with DLBCL, 2363 (58.8%) patients received both chemotherapy and rituximab and 740 (18.4%) patients received chemotherapy alone, while 1612 (40.1%) and 914 (22.8%) patients received no rituximab or chemotherapy, respectively. On multivariable analysis, low SES was associated with lesser use of chemotherapy (odd ratio [OR] 0.44; 95% CI 0.34-0.57) and rituximab (OR 0.41; 95% CI 0.32-0.52). The socioeconomic disparity for either treatment showed no secular trend of change. Additionally, patients with low SES showed increased excess mortality, with a hazard ratio of 2.34 (95% CI 1.67-3.28). Improving survival outcomes for patients with DLBCL requires provision of best available medical care and securing access to treatment regardless of patients' SES.

The changing context of hepatitis D

The global epidemiology of hepatitis D is changing with the widespread implementation of vaccination against hepatitis B. In high-income countries that achieved optimal control of HBV, the epidemiology of hepatitis D is dual, consisting of an ageing cohort of domestic patients with advanced liver fibrosis who represent the end stage of the natural history of HDV, and of a younger generation of immigrants from endemic countries who account for the majority of new infections. As observed in Europe in the 1980s, the distinctive clinical characteristic of chronic hepatitis D in endemic countries is the accelerated progression to cirrhosis and hepatocellular carcinoma. Despite some recent progress, the therapeutic management of HDV remains unsatisfactory, as most patients are not cured of HDV with currently available medicines. This review article describes the current epidemiology and clinical features of chronic hepatitis D, based on the literature published in the last 10 years.

Seroepidemiology of hepatitis A and B in the general population in Hong Kong: protocol of a cross-sectional survey using spatial sampling in a highly urbanised city

INTRODUCTION

Differences in immunisation policies have significantly reshaped the epidemiology of hepatitis A and B in the population. Assessment of the susceptibility and transmission potential of these two types of vaccine-preventable hepatitis would enhance the capacity of public health authorities for viral hepatitis elimination. Focusing on Hong Kong, the objectives of this study comprise the determination of the population-level seroprevalence of hepatitis A and B and an examination of the risk factors for virus transmission and the population impacts of vaccinations.

METHODS AND ANALYSIS

This is a cross-sectional household survey on hepatitis A and B. By using socially homogeneous building groups as sampling frame, eligible members of 1327 spatially selected households would be invited to complete a questionnaire and provide blood samples for serological testing (anti-hepatitis A virus, hepatitis B surface antigen, hepatitis B surface and core antibody). The main measures comprise a set of metrics on the prevalence of hepatitis A and B. Analysis would be conducted to examine the association of risk factors with the tested markers and describe the attitudes towards viral hepatitis vaccination.

ETHICS AND DISSEMINATION

Ethical approval from the Joint Chinese University of Hong Kong-New Territories East Cluster Clinical Research Ethics Committee, and approval for laboratory safety from the Chinese University of Hong Kong have been obtained. The study results will be presented in scientific forums to update on the epidemiology of hepatitis A and B and inform the development of new vaccination strategies in Hong Kong.

TRIAL REGISTRATION NUMBER

NCT04371276.

Association Between Income and Hepatitis B Seroprevalence: A Systematic Review and Meta-analysis

Context: Hepatitis B serology is very important for both diagnosis and treatment of the diseases. However, evidence regarding the association between income and hepatitis B seroprevalence are not sufficient to make a definitive conclusion. Objectives: This meta-analysis aimed to investigate the association between income inequality and hepatitis B seroprevalence. Methods: We searched PubMed and Web of Science databases to identify all relevant epidemiological studies published up to February 10, 2020. A categorical meta-analysis was applied to pool risk effects of income on hepatitis B seroprevalence. Results: A total of 1525 pieces of literature related to income level and hepatitis B seroprevalence were retrieved, of which 10 articles were finally included. The results revealed a borderline risk (OR: 1.14, 95%CI: 1.00 - 1.30) for hepatitis B seroprevalence (positive for one or more seromarkers) among low-income groups. A significant income effect was observed for HBsAg seroprevalence with a 28% higher risk for low income versus high cases (OR: 1.28, 95%CI: 1.16 - 1.41). However, no statistically significant associations were found between seroprevalence of Anti-HBs, Anti-HBc, and income. Conclusions: This study demonstrated that low income may increase the risk of hepatitis B seroprevalence, especially for HBsAg seroprevalence. Programs on hepatitis B prevention should focus on those with low income. Further studies are warranted to establish causality.

Hepatitis B Virus Seropositivity Is a Poor Prognostic Factor of Pediatric Hepatocellular Carcinoma: a Population-Based Study in Hong Kong and Singapore

Background

Hepatocellular carcinoma (HCC) is a rare hepatic malignancy in children. Hepatitis B virus (HBV) infection is a key predisposing factor in endemic regions but its impact on outcome has not been studied. We aim to evaluate the prognostic implication of HBV seropositivity and role of cancer surveillance in children with HCC from East Asian populations with national HBV vaccination.

Methods

Review of population-based databases for patients (< 18 years old) diagnosed with HCC from 1993 to 2017 in two Southeast Asian regions with universal HBV vaccination (instituted since 1988 and 1987 in Hong Kong and Singapore, respectively).

Results

Thirty-nine patients were identified (Hong Kong, 28; Singapore, 11). Thirty were male; median age at diagnosis was 10.8 years (range, 0.98-16.6). Abdominal pain was the commonest presentation while five patients were diagnosed through surveillance for underlying condition. Alpha-fetoprotein was raised in 36 patients (mean, 500,598 ng/ml). Nineteen had bilobar involvement, among the patients in whom pretreatment extent of disease (PRETEXT) staging could retrospectively be assigned, 3 had stage I, 13 had stage II, 4 had stage III, and 11 had stage IV disease. Seventeen had distant metastasis. HBsAg was positive in 19 of 38 patients. Two patients had fibrolamellar HCC. Upfront management involved tumor resection in 16 (liver transplantation, 2), systemic chemotherapy in 21, interventional procedures in 6 [transarterial chemoembolization (TACE), 5, radiofrequency ablation (RFA), 1], and radiotherapy in 4 (selective internal radiation, 3, external beam radiation, 1). Five-year event-free survival (EFS) and overall survival (OS) were 15.4 ± 6.0 and 26.1 ± 7.2%, respectively. Patient's HBsAg positivity, metastatic disease and inability to undergo definitive resection represent poor prognostic factors in univariate and multivariable analyses. Patients diagnosed by surveillance had significantly better outcome.

Conclusion

Pediatric HCC has poor outcome. HBV status remains relevant in the era of universal HBV vaccination. HBV carrier has inferior outcome and use of surveillance may mitigate disease course.

Risk of Hepatitis E among Persons Who Inject Drugs in Hong Kong: A Qualitative and Quantitative Serological Analysis

Hepatitis E virus (HEV) is an important cause of hepatitis, which can be transmitted via the bloodborne route. However, risk of hepatitis E among persons who inject drugs (PWIDs) is poorly understood. This study aimed to elucidate whether PWIDs are at risk for hepatitis E. We performed HEV IgM, IgG and nucleic acid detection on a cohort of 91 PWIDs and 91 age- and sex-matched organ donors. Blood HEV IgG was measured using the WHO HEV antibody standard. The effects of age, gender and addictive injection use on HEV serostatus and concentration were assessed. HEV IgG seroprevalence was 42/91 (46.2%) in the PWID group and 20/91 (22%) in the donor group (odds ratio = 3.04 (1.59–5.79), p = 0.0006). The median HEV IgG concentration was 5.8 U/mL (IQR: 2.5–7.9) in the PWID group and 2.1 U/mL (IQR: 1.2–5.3) in the donor group (p = 0.005). Increasing age and addictive injection use were significantly associated with HEV IgG serostatus, but only addictive injection use was associated with HEV IgG concentration (p = 0.024). We conclude that PWIDs are at increased risk for hepatitis E and are prone to repeated HEV exposure and reinfection as indicated by higher HEV IgG concentrations.

High incidence of hepatocellular carcinoma and cirrhotic complications in patients with psychiatric illness: a territory-wide cohort study

Background

Because of high-risk behaviours, sedentary lifestyle and side effects of medications, psychiatric patients are at risk of viral hepatitis, alcohol-related liver disease and non-alcoholic fatty liver disease. We aimed to study the incidence of hepatocellular carcinoma (HCC) and cirrhotic complications in psychiatric patients.

Methods

We identified consecutive adult patients in all public hospitals and clinics in Hong Kong with psychiatric diagnoses between year 2003 and 2007 using the Clinical Data Analysis and Reporting System, which represents in-patient and out-patient data of approximately 80% of the 7.4-million local population. The patients were followed for liver-related events (HCC and cirrhotic complications) and deaths until December 2017. Age- and sex-standardized incidence ratio (SIR) of HCC in psychiatric patients to the general population was estimated by Poisson model.

Results

We included 105,763 psychiatric patients without prior liver-related events in the final analysis. During a median (interquartile range) follow-up of 12.4 (11.0–13.7) years, 1461 (1.4%) patients developed liver-related events; 472 (0.4%) patients developed HCC. Compared with the general population, psychiatric patients had increased incidence of HCC (SIR 1.42, 95% confidence interval [CI] 1.28–1.57, P < 0.001). The SIR was highest in patients with drug-induced (SIR 3.18, 95% CI 2.41–4.11, P < 0.001) and alcohol-induced mental disorders (SIR 2.98, 95% CI 2.30–3.81, P < 0.001), but was also increased in patients with psychotic disorders (SIR 1.39, 95% CI 1.16–1.65, P < 0.001) and mood disorders (SIR 1.16, 95% CI 1.00–1.34, P = 0.047). Liver disease was the fifth most common cause of death in this population, accounting for 595 of 10,614 (5.6%) deaths. Importantly, 569 (38.9%) patients were not known to have liver diseases at the time of liver-related events. The median age at HCC diagnosis (61 [range 26–83] years) was older and the median overall survival (8.0 [95% CI 5.0–10.9] months) after HCC diagnosis was shorter in this cohort of psychiatric patients than other reports from Hong Kong.

Conclusions

HCC, cirrhotic complications, and liver-related deaths are common in psychiatric patients, but liver diseases are often undiagnosed. More efforts are needed to identify liver diseases in the psychiatric population so that treatments and screening for HCC and varices can be provided to patients in need.

Management of viral hepatitis A, C, D and E in pregnancy

Viral hepatitis can cause significant maternal and neonatal morbidity and mortality. Hepatitis A and E mainly present as acute hepatitis during pregnancy, while hepatitis C and D are usually found as chronic infection in pregnant women. Hepatitis A remains self-limiting during pregnancy while hepatitis E has a higher prevalence and manifests with a rigorous course in pregnant women. Screening of hepatitis C during pregnancy and its subsequent management during pregnancy are still a debatable topic. New treatments of hepatitis C and E require further evaluation for use in pregnancy. This review summarizes the prevalence, clinical manifestations, maternal, foetal and neonatal effects, and the management of hepatitis A, C, D and E viral infection during pregnancy.

An Aging Population of Chronic Hepatitis B With Increasing Comorbidities: A Territory-Wide Study From 2000 to 2017

Patients with chronic hepatitis B (CHB) are aging because of improved survival under better health care. This has an important implication on the choice of antiviral treatment (AVT), given that long-term safety would be a concern in the presence of multiple comorbidities. We aimed to determine the prevalence of key comorbidities and concomitant medications in a territory-wide CHB cohort in Hong Kong in 2000-2017. CHB patients who have been under the care at primary, secondary, and tertiary medical centers in the public sector were identified through the Clinical Data Analysis and Reporting System of the Hospital Authority, Hong Kong. The demographics and prevalence of key comorbidities, including diabetes mellitus, hypertension, chronic kidney disease, osteopenia/osteoporosis based on diagnosis codes, relevant medications, and/or laboratory parameters, were determined according to CHB patients' first appearance in four time periods: 2000-2004, 2005-2009, 2010-2013, and 2014-2017. In the final analysis, 135,395 CHB patients were included; the mean age increased with time: 41 ± 15 years in 2000-2004; 46 ± 17 years in 2005-2009; 51 ± 16 years in 2010-2013; and 55 ± 15 years in 2014-2017. There was a trend of increasing prevalence of several common comorbidities over the four periods: hypertension 25.5%, 23.8%, 27.2%, and 28.6%; diabetes mellitus 10.6%, 12.5%, 16.1%, and 20.1%; cardiovascular disease 12.5%, 16.9%, 20.9%, and 22.2%; and malignancy 7.0%, 13.2%, 17.3%, and 23.6%, respectively (all P < 0.001). Conclusion: CHB patients are getting older with increasing prevalence of common comorbidities. These comorbidities should be taken into account when choosing AVT.

Hepatitis E virus infection in Hong Kong blood donors

BACKGROUND AND OBJECTIVES

In Hong Kong, the dominant circulating hepatitis E virus (HEV) genotype is type 4, which can cause more severe clinical consequences than type 3. The aim of this study was to determine the HEV prevalence in Hong Kong blood donors.

MATERIALS AND METHODS

Unlinked donation samples (n = 10 000) collected in March to May 2015 were tested for HEV RNA using the Procleix HEV assay in an individual donation format (IDT). A subset of 2000 samples were tested for IgG and IgM anti-HEV using the Wantai enzyme-linked immunosorbent assay (ELISA). Nucleic acid testing (NAT) initial reactive results were retested once, and repeatedly reactive donations were subjected to alternative molecular procedures as confirmation tests.

RESULTS

One in 5000 Hong Kong blood donors was positive for HEV RNA (0·02%). The two RNA positive samples were also IgG and IgM anti-HEV positive. One of the two RNA positive donors could be sequenced revealing genotype type 4. Anti-HEV seroprevalence was estimated as 15·5% among all donors. IgG anti-HEV positive rate for age group 16-20 was 3·1%, and it increased with age to 43·1% for age group 51-60. Sero-positivity was higher in males (male donors 18·1% vs. female donors 13·2%), but it was mostly due to the difference in a specific age group (41-50).

CONCLUSION

Hepatitis E virus RNA positive rate of 0·02% was within the reported range of HEV RNA frequency in developed countries. One donor was confirmed to be genotype 4, which is the dominant genotype in circulation in Hong Kong.