Influence of chronic HBV infection on superimposed acute hepatitis E

The Re-Emergence of Hepatitis E Virus in Europe and Vaccine Development

Hepatitis E virus (HEV) is one of the leading causes of acute viral hepatitis. Transmission of HEV mainly occurs via the fecal-oral route (ingesting contaminated water or food) or by contact with infected animals and their raw meat products. Some animals, such as pigs, wild boars, sheep, goats, rabbits, camels, rats, etc., are natural reservoirs of HEV, which places people in close contact with them at increased risk of HEV disease. Although hepatitis E is a self-limiting infection, it could also lead to severe illness, particularly among pregnant women, or chronic infection in immunocompromised people. A growing number of studies point out that HEV can be classified as a re-emerging virus in developed countries. Preventative efforts are needed to reduce the incidence of acute and chronic hepatitis E in non-endemic and endemic countries. There is a recombinant HEV vaccine, but it is approved for use and commercially available only in China and Pakistan. However, further studies are needed to demonstrate the necessity of applying a preventive vaccine and to create conditions for reducing the spread of HEV. This review emphasizes the hepatitis E virus and its importance for public health in Europe, the methods of virus transmission and treatment, and summarizes the latest studies on HEV vaccine development.

Detection of HEV RNA Using One-Step Real-Time RT-PCR in Farrow-to-Finish Pig Farms in Bulgaria

(1) Background: HEV is a zoonotic, foodborne pathogen. It is spread worldwide and represents a public health risk. The aim of this study was to evaluate the presence of HEV RNA in farrow-to-finish pig farms in different regions of Bulgaria; (2) Methods: Isolation of HEV RNA from pooled samples of feces was performed using a QIAamp^® Viral RNA Mini Kit followed by HEV RNA detection using a single-step real-time RT-PCR with primers and probes targeting the ORF 3 HEV genome; (3) Results: HEV RNA was detected in 12 out of 32 tested farms in Bulgaria (37.5%). The overall percentage of HEV-positive pooled fecal samples was 10.8% (68 of 630 samples). HEV was detected mostly in pooled fecal samples from finisher pigs (66/320, 20.6%) and sporadically from dry sows (1/62, 1.6%) and gilts (1/248, 0.4%); (4) Conclusions: Our results confirm that HEV circulates in farrow-to-finish pig farms in Bulgaria. In our study, we found HEV RNA in pooled fecal samples from fattening pigs (4-6-months age), shortly before their transport to the slaughterhouse indicating a potential risk to public health. The possible circulation of HEV throughout pork production requires monitoring and containment measures.

Clinical Conundrum of Acute Hepatitis B With Concurrent Hepatitis E Infection Leading to Severe Acute Liver Injury

Acute liver injury in the setting of acute fulminant hepatitis caused by the hepatitis B virus (HBV) can occur both during primary infection and after chronic HBV reactivation. Guidelines recommend considering antiviral therapy in both cases. Antiviral therapy with a nucleoside analog may be beneficial in patients with acute liver failure from acute HBV infection, though not all studies have shown a benefit. This is a case of a 53-year-old woman with a past medical history of untreated hepatitis C with undetectable viral load and right breast cancer status post lumpectomy, who presented to the emergency department with complaints of yellowish skin and sclera discoloration with right upper quadrant pain for one week. She was a known intravenous drug abuser and binge alcohol user. Her labs were positive for hepatitis B, hepatitis E, and hepatitis C viruses. She also had elevated liver enzymes with hyperbilirubinemia showing severe acute liver injury. Computed tomography of the abdomen and pelvis with contrast was normal, and the abdominal ultrasound showed homogenous echotexture of the liver without a focal lesion. The patient was diagnosed with acute fulminant hepatitis B. After initial hemodynamic stabilization, N-acetylcysteine (NAC) and tenofovir were started, and transaminases were followed. Liver function tests showed a downtrend, and, in a few weeks, they came to baseline. Hepatitis B viral load became undetectable as well. Acute hepatitis B infection is seldom treated. The presented case depicts the use of tenofovir in the setting of severe acute liver injury due to hepatitis B. Starting antiviral therapy (especially tenofovir disoproxil fumarate) early in the disease course was shown to have very assuring results with complete resolution of symptoms and normalization of liver function tests. The treatment protocol for acute HBV deserves further investigation.

Prognosis of hepatitis E infection in patients with chronic liver disease: A meta-analysis

In individuals with underlying chronic liver disease (CLD), hepatitis E virus (HEV) infection is a potential trigger of acute-on-chronic liver failure. In this systematic review, seven electronic databases were searched. Pooled incidence rates with 95% confidence intervals (95% CIs) were calculated by the Freeman-Tukey double arcsine transformation method. The association between death or liver failure and HEV superinfection in CLD patients was estimated by the odds ratios (OR) with a 95% CI. A total of 18 studies from 5 countries were eligible for systematic review. The prevalence of acute HEV infection in hospitalized CLD patients with clinical manifestations of hepatitis was 13.6%, which was significantly higher than that in CLD patients from the community (pooled prevalence 1.1%). The overall rates of liver failure and mortality in CLD patients with HEV superinfection were 35.8% (95% CI: 26.7%-45.6%) and 14.3% (95% CI: 10.6%-18.5%), respectively, with the rates in cirrhotic patients being approximately 2-fold and 4-fold higher than those in noncirrhotic patients, respectively. The risks of liver failure (OR = 5.5, 95% CI: 1.5-20.1) and mortality (OR = 5.0, 95% CI: 1.9-13.3) were significantly higher in CLD patients with HEV superinfection than in those without HEV superinfection. HEV testing in hospitalized CLD patients is necessary due to the high prevalence of HEV infection observed in hospitalized CLD patients. HEV superinfection could accelerate disease progression in patients with underlying CLD and increase mortality in these patients. HEV vaccination is appropriate for patients with pre-existing CLD.

Dual Infection of Hepatitis A Virus and Hepatitis E Virus- What Is Known?

Viral hepatitis is an infection of human hepatocytes resulting in liver damage. Dual infection of two hepatotropic viruses affects disease outcomes. The hepatitis A virus (HAV) and hepatitis E virus (HEV) are two enterically transmitted viruses; they are single-stranded RNA viruses and have common modes of transmission. They are transmitted mainly by the fecal-oral route and ingestion of contaminated food, though the HAV has no animal reservoirs. The HAV and HEV cause acute self-limiting disease; however, the HEV, but not HAV, can progress to chronic and extrahepatic infections. The HAV/HEV dual infection was reported among acute hepatitis patients present in developing countries. The impact of the HAV/HEV on the prognosis for acute hepatitis is not completely understood. Studies showed that the HAV/HEV dual infection increased abnormalities in the liver leading to fulminant hepatic failure (FHF) with a higher mortality rate compared to infection with a single virus. On the other hand, other reports showed that the clinical symptoms of the HAV/HEV dual infection were comparable to symptoms associated with the HAV or HEV monoinfection. This review highlights the modes of transmission, the prevalence of the HAV/HEV dual infection in various countries and among several study subjects, the possible outcomes of this dual infection, potential model systems for studying this dual infection, and methods of prevention of this dual infection and its associated complications.

Treatment of Hepatitis E

Hepatitis E virus (HEV) infections are the most common cause of acute hepatitis, but they can also take a chronic course. There is no specific therapy for acute hepatitis, and current treatment is supportive. Choosing ribavirin as the first-line therapy for chronic HEV is advisable, especially immunosuppressed individuals. Moreover, ribavirin therapy in the acute phase of infection provides major benefits for those at high risk of acute liver failure (ALF)/acute-on-chronic liver failure (ACLF). Pegylated interferon α has been used successfully for treatment of hepatitis E but is associated with major side effects. Cholestasis is one of the most common, but devastating, manifestations in hepatitis E. Current therapy for HEV aims to treat symptoms. Therapy generally involves several measures, such as vitamins, albumin, and plasma for supporting treatment, symptomatic treatment for cutaneous pruritus, ursodeoxycholic acid, Obeticholic acid, S-adenosylmethionine, etc. for removing jaundice. HEV infection during pregnancy and patients with underlying liver disease may develop liver failure. For these patients, active monitoring, standard care, and supportive treatment are the foundations. Ribavirin has successfully been used to prevent liver transplantation (LT). Prevention and treatment of complications are important for treatment of liver failure. Liver support devices are intended to support liver function until such time as native liver function recovers, or until LT. LT is widely considered as irreplaceable and definitive treatment for liver failure, particularly for patients who do not improve with supportive measures to sustain life.

Acute hepatitis E virus superinfection increases mortality in patients with cirrhosis

Background

Although acute hepatitis E is not fatal in healthy individuals, it is unclear whether hepatitis E superinfection increases the mortality in patients with pre-existing liver disease. Thus, we investigated the prognosis of patients with acute hepatitis E according to their cirrhosis diagnosis, and the prognosis according to the development of acute-on-chronic liver failure (ACLF) in patients with cirrhosis and chronic liver disease (CLD).

Methods

This study included 74 consecutive patients who were diagnosed with acute viral hepatitis E between January 2007 and December 2019. Of them, 39 patients without CLD, 13 patients with non-cirrhotic CLD, and 22 patients with cirrhotic CLD were analyzed.

Results

Among the 74 patients with HEV infection, 7 (9.5%) died within 180 days: 5 with underlying cirrhosis (71.4%) and 2 without cirrhosis (28.6%). The 180-day mortality was significant higher for patients with cirrhosis than for patients without cirrhosis (22.7% vs. 3.8%, P = 0.013). The age- and sex-adjusted proportional-hazard model revealed an approximately eightfold increase in the 180-day mortality risk in patients with cirrhosis compared to patients without cirrhosis. In addition, development of hepatitis E virus-related ACLF due to acute liver function deterioration in patients with pre-existing CLD or cirrhosis worsened the 180-day mortality rate.

Conclusions

Our findings suggest that the acute hepatitis E mortality rate was low in healthy individuals but higher in patients with cirrhosis, and especially high in those with ACLF.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07050-w.

Serum superoxide dismutase level is a potential biomarker of disease prognosis in patients with HEV-induced liver failure

Background

Viral hepatitis E clinically ranges from self-limiting hepatitis to lethal liver failure. Oxidative stress has been shown to mediate hepatic inflammation during HBV-induced liver failure. We investigated whether a biomarker of oxidative stress may be helpful in assessing severity and disease outcomes of patients with HEV-induced liver failure.

Methods

Clinical data were obtained from patients with HEV-induced acute viral hepatitis (AVH, n = 30), acute liver failure (ALF, n = 17), and acute-on-chronic liver failure (ACLF, n = 36), as well as from healthy controls (HC, n = 30). The SOD and HMGB1 levels were measured in serum by ELISA. HL-7702 cells were cultured and stimulated by serum from HEV-infected patients or by HMGB1; oxidative status was investigated by CellROX and apoptosis was investigated by flow cytometry.

Results

Patients with HEV-induced liver failure (including ALF and ACLF) showed increased SOD levels compared with HEV-AVH patients and healthy controls. SOD levels > 400 U/mL were associated with a significantly higher risk of mortality in HEV-ALF and HEV-ACLF patients. Serum from HEV-infected patients led to ROS accumulation, HMGB1 secretion, and apoptosis in HL-7702 cells. Antioxidant treatment successfully inhibited HEV-induced HMGB1 secretion, and HMGB1 promoted apoptosis in HL-7702 cells.

Conclusion

HEV increased oxidative stress in the pathogenesis of HEV-induced hepatic diseases. Early testing of serum SOD may serve as a predictor of both HEV-ALF and HEV-ACLF outcomes. Moreover, development of strategies for modulating oxidative stress might be a potential target for treating HEV-induced liver failure patients.

Advances in Hepatitis E Virus Biology and Pathogenesis

Hepatitis E virus (HEV) is one of the causative agents for liver inflammation across the world. HEV is a positive-sense single-stranded RNA virus. Human HEV strains mainly belong to four major genotypes in the genus Orthohepevirus A, family Hepeviridae. Among the four genotypes, genotype 1 and 2 are obligate human pathogens, and genotype 3 and 4 cause zoonotic infections. HEV infection with genotype 1 and 2 mainly presents as acute and self-limiting hepatitis in young adults. However, HEV infection of pregnant women with genotype 1 strains can be exacerbated to fulminant hepatitis, resulting in a high rate of case fatality. As pregnant women maintain the balance of maternal-fetal tolerance and effective immunity against invading pathogens, HEV infection with genotype 1 might dysregulate the balance and cause the adverse outcome. Furthermore, HEV infection with genotype 3 can be chronic in immunocompromised patients, with rapid progression, which has been a challenge since it was reported years ago. The virus has a complex interaction with the host cells in downregulating antiviral factors and recruiting elements to generate a conducive environment of replication. The virus-cell interactions at an early stage might determine the consequence of the infection. In this review, advances in HEV virology, viral life cycle, viral interference with the immune response, and the pathogenesis in pregnant women are discussed, and perspectives on these aspects are presented.

Prognostic Significance of End-Stage Liver Diseases, Respiratory Tract Infection, and Chronic Kidney Diseases in Symptomatic Acute Hepatitis E

Symptomatic hepatitis E virus (HEV) infection is sporadic, and usually occurs in a limited number of infected patients, which hinders the investigation of risk factors for clinical outcomes in patients with acute HEV infection. A retrospective cohort study enrolling 1913 patients with symptomatic acute hepatitis E in Beijing 302 Hospital from January 1, 2001 to December 31, 2018 was conducted. The baseline characteristics, clinical features and laboratory data of these HEV infection cases were analyzed. Albumin (ALB), platelet (PLT), alanine aminotransferase (ALT), total bilirubin (T-BiL), international normalized ratio (INR) and serum creatinine (SCR) levels, along with the model for end-stage liver disease (MELD) score, hospitalization days, co-morbidity number and mortality were taken as major parameters for comparing the clinical manifestations in our study. We found that not all pre-existing chronic liver diseases exacerbate clinical manifestations of acute hepatitis E. Alcoholic hepatitis, fatty liver hepatitis, hepatic cyst, drug-induced hepatitis and hepatocellular carcinoma were not significantly associated with mortality of HEV patients. Among all of the comorbidities, end-stage liver diseases (ESLDs, including ascites, cirrhosis, hepatic coma and hepatorenal syndrome), respiratory tract infection and chronic kidney diseases (CKDs, including renal insufficiency and renal failure) were found to remarkably increase the mortality of patients with symptomatic HEV infection. Furthermore, the severity evaluation indexes (SEI), such as MELD score, duration of hospital stay, and co-morbidity number in HEV patients with underlying comorbidities were much worse than that of their counterparts without relevant comorbidities.

HEV and HBV Dual Infection: A Review

Hepatitis E virus (HEV) is a global health problem, affecting about 20 million people worldwide. There is significant overlap of hepatitis B virus (HBV) and HEV endemicity in many Asian countries where dual infections with HEV and HBV can occur. Though the clinical course of HEV is largely self-limited, HEV superinfection in patients with chronic hepatitis B (CHB) can result in acute exacerbation of underlying CHB. HEV superinfection in patients with CHB-related cirrhosis has been identified as a risk factor for decompensated cirrhosis and an independent predictor of mortality. Whereas acute HEV infection in pregnancy can cause fulminant liver failure, the few studies on pregnant patients with dual HBV and HEV infection have shown a subclinical course. Immunosuppression is a risk factor for the development of chronic HEV infection, which can be managed by decreasing the dose of immune-suppressants and administering ribavirin. Vaccination for HEV has been developed and is in use in China but its efficacy in patients with CHB has yet to be established in the USA. In this review, we appraise studies on dual infection with HEV and HBV, including the effect of HEV superinfection and coinfection in CHB, management strategies used and the role of active vaccination in the prevention of HEV.

Seroconversion of HBsAG coincides with hepatitis A super-infection: A case report

BACKGROUND

Hepatitis B virus (HBV) is a hepatotropic virus that can cause acute and chronic liver damage. According to the world health organization 257 million people are infected with chronic HBV infection worldwide. Super-infection with other hepadnaviruses, including hepatitis A virus (HAV), hepatitis C virus, hepatitis D virus, and hepatitis E virus is associated with increased risk of acute liver failure in patients with chronic HBV.

CASE SUMMARY

Here, we report a case of a 47-year old male patient with HBV-related compensated Child A cirrhosis, who presented with general fatigue, malaise and laboratory signs of acute hepatitis. Although the patient was regularly seen at a specialized university liver unit, the HAV vaccination status was unclear. Acute HAV super-infection was diagnosed by positive serological and polymerase chain reaction analysis. Following acute HAV super-infection, spontaneous HBsAg elimination and development of an anti-HBs titer were observed.

CONCLUSION

This case illustrates the importance of carefully checking the vaccination status. In our patient, unspecific immunological responses to HAV led to functional cure of HBV.

Poor Outcomes of Acute Hepatitis E in Patients With Cirrhotic Liver Diseases Regardless of Etiology

Background: Chronic liver diseases (CLDs) have been documented to exacerbate clinical outcomes of acute hepatitis E (AHE). This study aimed to uncover the role of etiology and status of CLD in the adverse outcomes of AHE. We found that superinfection with hepatitis E virus (HEV) in patients with cirrhotic CLD can cause a worsen outcome, leading to exacerbation of AHE, compared with HEV-infected patients without CLD or with noncirrhotic CLD. Additional analysis revealed that the etiology of CLD is not associated with outcomes of AHE patients. These finding suggests that the overall liver status plays a predominant role in determining the outcomes of AHE.

Updates in Hepatitis E virus (HEV) field; lessons learned from human liver chimeric mice

Hepatitis E virus (HEV) is the most common cause of viral hepatitis globally, and it is an emerging pathogen in developed countries. In vivo studies of HEV have long been hindered due to the lack of an efficient small animal model. Recently, human liver chimeric mice were described as an elegant model to study chronic HEV infection. HEV infection was established in mice with humanized liver that were challenged with stool preparations containing HEV genotype (gt)1 and/or gt3. An increase in viral load and the level of HEV Ag in mouse samples were markers of active infection. Plasma-derived HEV preparations were less infectious. The kinetics of HEV ORF2 Ag during HEV infection and its impact on HEV diagnosis were described in this model. In addition, the nature of HEV particles and HEV ORF2 Ag were characterized. Moreover, humanized mice were used to study the impact of HEV infection on the hepatic innate transcriptome and evaluation of anti-HEV therapies. This review highlights recent advances in the HEV field gathered from well-established experimental mouse models, with an emphasis on this model as a tool for elucidating the course of HEV infection, the study of the HEV life cycle, the interaction of the virus with the host, and the evaluation of new anti-HEV therapies.

Increased liver injury in patients with chronic hepatitis and IgG directed against hepatitis E virus

Type-E hepatitis is responsible for more than three million symptomatic cases and more than 40,000 deaths worldwide. The situation of this hepatitis is overall poorly known in sub-Saharan Africa. Notably, the baseline circulation of HEV outside sporadic outbreaks has been barely characterized in this large region. More specifically, the impact of superinfection by this virus on the health status of the large reservoir of patients chronically infected with other hepatitis viruses remains to be evaluated. We searched for anti-HEV immunoglobulins in a series of 200 pregnant women and 92 patients with persistent liver infections with hepatitis B or C viruses and subsequently tried to assess serological co-variations with demographical and clinical features. We observed that only 1.5 % of expectant mothers were seropositive of anti-HEV IgG while it was the case for 18.4 % of patients with chronic liver diseases (P=4.5E-07). The presence of anti-HEV was not linked to any of the collected demographical features (age, sex, education, pork meat consumption, water supply, …). By contrast, the presence of anti-HEV was significantly associated with increased levels (1.6-1.8-fold, P<0.0001) of blood aminotransferases (AST, ALT) in patients with persistent hepatitis B or C. Our work indicates that, in Ivory Coast, the presence of IgG directed against HEV might contribute to a deterioration of liver health in patients with already installed persistent liver infections. The mechanisms explaining such phenomenon at distance of acute phase of infection are still unknown but might be linked either to a residual persistence of HEV in a context of general immune exhaustion or to an inappropriate auto-immune reaction as already observed in the aftermath of other viral infection types.

Superinfective Hepatitis E Virus Infection Aggravates Hepatocytes Injury in Chronic Hepatitis B

Hepatitis E virus (HEV) infection is a major cause of morbidity in endemic areas. Its consequences among chronic hepatitis B (CHB) patients have been under-reported. The aim of this study was to assess the impact of superinfective HEV infection (acute and past) on virological and clinical features of patients with CHB infection. Clinical, biochemical, virological and immunological data of 153 CHB patients including 98 with hepatitis B virus (HBV) monoinfection and 55 with HBV-HEV superinfection with both HEV and HBV infection was retrospectively investigated and analyzed in this study conducted in Wuhan, China. An overall anti-HEV IgG seroprevalence was found to be 35.9% in CHB patients. HBV-HEV superinfection patients showed significantly higher rate of complications (ascites, hepato-renal syndrome & encephalopathy) (all with P=0.04), cirrhosis (P<0.001) and acute-on-chronic liver failure (P<0.001) than HBV monoinfection patients. They also displayed elevated ALTs (P<0.001) and total serum bilirubin (P<0.001) with diminished albumin (P<0.001) and HBV viral load (P<0.001). Cytokines assay revealed increased expression of IL-6 (P=0.02), IL-10 (P=0.009) and TNF-α (P=0.003) in HBV-HEV superinfection patients compared to HBV monoinfection patients. Our study demonstrated that HEV superinfection in CHB patients was associated with progressive clinical manifestation, which is likely due to the enhanced expression of cytokines related with hepatocytes necrosis. HEV was also associated with repressed HBV replication, but the underlying mechanism requires further investigation.

Genetic diversity of hepatitis B co-infection with hepatitis C, D and E viruses among Malaysian chronic hepatitis B patients

BACKGROUND

Hepatitis B virus co-infection with other strains of viral hepatitis is associated with increased risk of liver cirrhosis and hepatic decompensation.

OBJECTIVES

This is a prevalence study that assessed the genetic diversity of chronic hepatitis B patients and coinfection.

METHODS

Chronic hepatitis B patients enrolled in this study were tested for antibodies of other hepatitis viruses using ELISA kits. Patient clinical profiles were collected and partial genes of HBV, HCV, and HEV were amplified, sequenced, and analyzed using phylogenetic analysis. The associations between variables were determined using the chi-squared test.

RESULTS

Of the 82 patients recruited for this study, 53.7% were non-cirrhotic, 22.0% cirrhotic, 20.7% acute flare and 3.7% hepatocellular carcinoma. Majority (58%) of patients had a high level of ALT (≥34 U/L). Sequence analysis showed HBV (63.9%) belonged to genotype B, HEV belonged to genotype 4 while HCV belonged to genotype 3a and the genotypes were found to be significantly associated with the clinical stage of the patients (χ2=56.632; p<0.01). Similarly, Hepatitis B e antigen was also found to be significantly associated with the clinical stage of infection (χ2=51.952; p<0.01).

CONCLUSION

This study revealed that genetic diversity was found to have a significant impact on the severity of infection.

Comparison of hepatitis E virus seroprevalence between HBsAg-positive population and healthy controls in Shandong province, China

Background

Persons with chronic hepatitis B (CHB) infection were reported to suffer severe disease after hepatitis E virus (HEV) superinfection, but the studies regarding HEV seroprevalence in this population were limited. A recent study in Vietnam found higher HEV seroprevalence among CHB patients compared with healthy controls.

Methods

A community-based case-control study was conducted in two counties of Shandong province, China, where hepatitis E incidence was at the highest (Rushan) and lowest (Zhangqiu) in the province based on data from routine public health surveillance. Four townships were selected randomly from each county and all residents in these townships were tested for hepatitis B surface antigen (HBsAg). Those tested positive for HBsAg (CHB group) and the 1:1 age and sex-matched HBsAg-negative residents (control group) were included. Anti-HEV IgM and IgG were tested and positive rates of IgG and IgM were compared between the CHB group and the control group.

Results

In total, 2048 CHB participants and 2054 controls were included in the study. In the CHB group, HEV IgG seroprevalence was 9.16% (95% CI: 7.47–11.09) in Zhangqiue and 38.06% (95% CI: 35.07–41.19) in Rushan (P < 0.001); the corresponding rates of IgM were 0.1% (95% CI: 0.002–0.54) and 1.57% (95% CI: 0.90–2.53), respectively (P < 0.001). HEV IgG seroprevalence was similar between CHB group and the control group in both counties (P = 0.21, P = 0.47, respectively) and the same results were found for the positive rate of IgM (P = 0.103, P = 0.262, respectively). Multivariable analysis showed the status of HBsAg was not independently associated with the status of anti-HEV IgG in either Zhangqiu or Rushan [P = 0.187, OR = 1.23(95% CI: 0.90, 1.68); P = 0.609, OR = 1.05 (95% CI: 0.87, 1.26)].

Conclusions

The seroprevalence of HEV varies greatly in different geographic areas, but the seroprevalence is similar between populations with and without CHB. CHB patients residing in high HEV endemic areas might be at higher risk for HBV-HEV superinfection.

Public health risks associated with hepatitis E virus (HEV) as a food-borne pathogen

Hepatitis E virus (HEV) is an important infection in humans in EU/EEA countries, and over the last 10 years more than 21,000 acute clinical cases with 28 fatalities have been notified with an overall 10-fold increase in reported HEV cases; the majority (80%) of cases were reported from France, Germany and the UK. However, as infection in humans is not notifiable in all Member States, and surveillance differs between countries, the number of reported cases is not comparable and the true number of cases would probably be higher. Food-borne transmission of HEV appears to be a major route in Europe; pigs and wild boars are the main source of HEV. Outbreaks and sporadic cases have been identified in immune-competent persons as well as in recognised risk groups such as those with pre-existing liver damage, immunosuppressive illness or receiving immunosuppressive treatments. The opinion reviews current methods for the detection, identification, characterisation and tracing of HEV in food-producing animals and foods, reviews literature on HEV reservoirs and food-borne pathways, examines information on the epidemiology of HEV and its occurrence and persistence in foods, and investigates possible control measures along the food chain. Presently, the only efficient control option for HEV infection from consumption of meat, liver and products derived from animal reservoirs is sufficient heat treatment. The development of validated quantitative and qualitative detection methods, including infectivity assays and consensus molecular typing protocols, is required for the development of quantitative microbial risk assessments and efficient control measures. More research on the epidemiology and control of HEV in pig herds is required in order to minimise the proportion of pigs that remain viraemic or carry high levels of virus in intestinal contents at the time of slaughter. Consumption of raw pig, wild boar and deer meat products should be avoided.

Investigation of underlying comorbidities as risk factors for symptomatic human hepatitis E virus infection

BACKGROUND

Symptomatic Hepatitis E virus (HEV) infection occurs in few infected subjects, and the risk factors are not completely known.

AIM

To explore the risk factors for adverse clinical outcomes in acute HEV infections.

METHODS

A large retrospective study was conducted. The baseline characteristics, clinical outcomes, and laboratory data of 512 acute HEV infection cases were analysed using logistic regression models.

RESULTS

All patients exhibited autochthonous sporadic HEV infections, and most were elderly. Their symptoms varied from asymptomatic to severe liver diseases. In all, 215 patients (42.0%) had liver failure and/or decompensation, and 45 (8.2%) patients died within 3 months. Nearly 60% of patients had underlying chronic liver diseases (CLDs), 20% were cirrhotic, and various extrahepatic underlying comorbidities were common. The logistic regression analysis revealed that underlying CLDs, especially cirrhosis, were closely associated with disease severity (OR = 8.78, P < 0.001) but not with mortality in patients with severe liver diseases. In addition to the known factors, including an old age, the male gender and CLDs, we identified pre-existing extrahepatic tumours, diabetes, and chronic respiratory and renal diseases as novel independent predictors for adverse clinical outcomes. Importantly, patients without these four extrahepatic comorbidities showed a much lower mortality rate (4.2%, P < 0.001) than patients with one (18.5%) or more comorbidities (34.5%).

CONCLUSIONS

Previous comorbidities, including tumours, diabetes, and chronic liver, lung and kidney diseases, were independent risk factors for adverse outcomes, especially mortality, in acute HEV infections. This study provides valuable data for improving the prevention and control of HEV infection.

Clinical features of acute hepatitis E super-infections on chronic hepatitis B

AIM

To examine the clinical features and risk factors for adverse outcomes in chronic hepatitis B (CHB) superimposed with hepatitis E virus (HEV).

METHODS

This retrospective cohort study included 228 patients with acute HEV infection (showing clinical acute hepatitis symptomology and positivity for anti-HEV immunoglobulin M) with underlying CHB (confirmed by positivity for hepatitis B surface antigen and/or hepatitis B virus (HBV) DNA over 6 mo) who had been admitted to the Shanghai Public Health Clinical Center, which represents the regional tertiary hospital for infectious diseases in Shanghai city, China. Data for adverse outcomes were collected, and included severe liver diseases (defined as liver failure and/or acute liver decompensation) and liver-related mortality. Logistic regression modeling was performed to determine the risk factors for adverse outcomes.

RESULTS

The symptoms caused by superimposed acute hepatitis E (AHE) were much more severe in cirrhotic patients (n = 94) than in non-cirrhotic patients (n = 134), as evidenced by significantly higher liver complications (77.7% vs 28.4%, P < 0.001) and mortality rate (21.3% vs 7.5%, P = 0.002). Most of the cirrhotic patients (n = 85, 90.4%) had no prior decompensation. Among the non-cirrhotic patients, superimposed AHE caused progressively more severe diseases that corresponded with the CHB disease stages, from immune tolerant to immune reactivation phases. Few risk factors were identified in the cirrhotic patients, but risk factors for non-cirrhotic patients were found to be intermediate HBV DNA levels (OR: 5.1, P = 0.012), alcohol consumption (OR: 6.4, P = 0.020), and underlying diabetes (OR: 7.5, P = 0.003) and kidney diseases (OR: 12.7, P = 0.005). Only 28.7% of the cirrhotic patients and 9.0% of the non-cirrhotic patients had received anti-HBV therapy previously and, in all cases, the efficacy had been suboptimal.

CONCLUSION

CHB-related cirrhosis and intermediate HBV DNA level were associated with severe disease in superinfected patients, and successful antiviral treatment might counter this outcome.

Characterization of the Specificity, Functionality, and Durability of Host T-Cell Responses Against the Full-Length Hepatitis E Virus

The interplay between host antiviral immunity and immunopathology during hepatitis E virus (HEV) infection determines important clinical outcomes. We characterized the specificity, functionality, and durability of host T-cell responses against the full-length HEV virus and assessed a novel "Quantiferon" assay for the rapid diagnosis of HEV infection. Eighty-nine volunteers were recruited from Oxford, Truro (UK), and Toulouse (France), including 44 immune-competent patients with acute HEV infection, 18 HEV-exposed immunosuppressed organ-transplant recipients (8 with chronic HEV), and 27 healthy volunteers. A genotype 3a peptide library (616 overlapping peptides spanning open reading frames [ORFs] 1-3) was used in interferon-gamma (IFN-γ) T-cell ELISpot assays. CD4⁺ /CD8⁺ T-cell subsets and polyfunctionality were defined using ICCS and SPICE analysis. Quantification of IFN-γ used whole-blood stimulation with recombinant HEV-capsid protein in the QuantiFERON kit. HEV-specific T-cell responses were detected in 41/44 immune-competent HEV exposed volunteers (median magnitude: 397 spot-forming units/10⁶ peripheral blood mononuclear cells), most frequently targeting ORF2. High-magnitude, polyfunctional CD4 and CD8⁺ T cells were detected during acute disease and maintained to 12 years, but these declined over time, with CD8⁺ responses becoming more monofunctional. Low-level responses were detectable in immunosuppressed patients. Twenty-three novel HEV CD4⁺ and CD8⁺ T-cell targets were mapped predominantly to conserved genomic regions. QuantiFERON testing demonstrated an inverse correlation between IFN-γ production and the time from clinical presentation, providing 100% specificity, and 71% sensitivity (area under the receiver operator characteristic curve of 0.86) for HEV exposure at 0.3 IU/mL.

CONCLUSION

Robust HEV-specific T-cell responses generated during acute disease predominantly target ORF2, but decline in magnitude and polyfunctionality over time. Defining HEV T-cell targets will be important for the investigation of HEV-associated autoimmune disease. (Hepatology 2016;64:1934-1950).

Incidence and seroprevalence of hepatitis E virus infection in pregnant women infected with hepatitis B virus and antibody placental transfer in infants

BACKGROUND

Hepatitis E has poor outcomes in pregnant women. Superinfection of hepatitis E virus (HEV) in patients infected with hepatitis B virus (HBV) may worsen liver disease.

OBJECTIVES

To estimate the incidence and seroprevalence of HEV infection among HBV-infected pregnant women, to investigate the transplacental transfer of maternal anti-HEV IgG, and to compare the maternal and neonatal outcomes in anti-HEV positive and negative pregnant women.

STUDY DESIGN

Totally 391 HBV-infected pregnant women were recruited from April 2012 to October 2014. Paired mothers and infants were followed up at an average 9.8 months postpartum. Anti-HEV IgG and IgM were tested by ELISA.

RESULTS

Of the pregnant women, none was anti-HEV IgM positive and 42 (10.7%) were IgG positive. At the follow-up, 3 seronegative women converted to anti-HEV IgG positive, with an estimated incidence of 17 per 1000 person-years. No significant differences of gestational age, preterm birth rate, Apgar score and birthweight were observed between newborns of anti-HEV IgG positive and negative mothers. Of the 42 neonates born to anti-HEV IgG positive mothers, 38 (90.5%) had anti-HEV IgG in their cord blood. The neonatal and maternal anti-HEV IgG levels were positively correlated (r=0.827, p<0.05). All infants were negative for both anti-HEV IgM and IgG at the follow-up.

CONCLUSIONS

HBV-infected pregnant women rarely have novel HEV infection during late pregnancy in Jiangsu, China. Maternal anti-HEV IgG efficiently transfers into the fetuses, and disappears in infants before 10 months old.

Epidemiology of hepatitis E virus in Iran

Iran is known as an endemic country for hepatitis E virus (HEV) infection, while there are variations in the epidemiology of HEV infection throughout the country. The available epidemiological studies in different regions of Iran show HEV seroprevalence of 1.1%-14.2% among general population, 4.5% -14.3% among blood donors, 6.1%-22.8% among injecting drug users, 6.3%-28.3% among hemodialysis patients, 1.6%-11.3% among patients infected with other hepatitis viruses, 27.5% among patients with chronic liver disease, 30.8% among kidney transplant recipient patients, and 10%-16.4% among human immunodeficiency virus-infected patients. These variations reflect differences in the status of public health and hygiene, risk factors, and routes of transmission in different regions and groups. Therefore, it is necessary to review the epidemiology of HEV infection to determine the most prevalent risk factors and routes of transmission, and to evaluate the effectiveness of preventive strategies employed in the public health services of the country. Moreover, the other epidemiological aspects of HEV, including the genotypic pattern, extra hepatic manifestations, and incidence of chronic infection need to be investigated among Iranian population to expand the current knowledge on the epidemiology of HEV and to clarify the real burden of HEV infection. Therefore, this review was performed to provide a general overview regarding the epidemiology of HEV in Iran.

Characteristics and Discrepancies in Acute-on-Chronic Liver Failure: Need for a Unified Definition

Background & Aim

To investigate the prevalence, mortalities, and patient characteristics of Acute-on-chronic liver failure (ACLF) according to the AARC (Asian Pacific Association for the Study of the Liver ACLF Research Consortium) and European Association for the Study of the Liver CLIF-C (Chronic Liver Failure Consortium) definitions.

Methods

We collected retrospective data for 1470 hospitalized patients with chronic liver disease (CLD) and acute deterioration between January 2013 and December 2013 from 21 university hospitals in Korea.

Results

Of the patients assessed, the prevalence of ACLF based on the AARC and CLIF-C definitions was 9.5% and 18.6%, respectively. The 28-day and 90-day mortality rates were higher in patients with ACLF than in those without ACLF. Patients who only met the CLIF-C definition had significantly lower 28-day and 90-day survival rates than those who only met the AARC definition (68.0% vs. 93.9%, P<0.001; 55.1% vs. 92.4%, P<0.001). Among the patients who had non-cirrhotic CLD, the 90-day mortality of the patients with ACLF was higher than of those without ACLF, although not significant (33.3% vs. 6.0%, P = 0.192). Patients with previous acute decompensation (AD) within 1- year had a lower 90-day survival rate than those with AD more than 1 year prior or without previous AD (81.0% vs. 91.9% or 89.4%, respectively, all P<0.001). Patients who had extra-hepatic organ failure without liver failure had a similar 90-day survival rate to those who had liver failure as a prerequisite (57.0% vs. 60.6%, P = 0.391).

Conclusions

The two ACLF definitions result in differences in mortality and patient characteristics among ACLF patients. We suggest that non-cirrhotic CLD, previous AD within 1 year, and extra-hepatic organ failure should be included in the ACLF diagnostic criteria. In addition, further studies are necessary to develop a universal definition of ACLF.

Treatment of Hepatitis E

Hepatitis E virus (HEV) infections are the most common cause of acute hepatitis, but they can also take a chronic course. There is no specific therapy for acute hepatitis, and current treatment is supportive. Choosing ribavirin as the first-line therapy for chronic HEV is advisable, especially in solid organ transplant patients. Pegylated interferon-α has been used successfully for treatment of hepatitis E but is associated with major side effects. Cholestasis is one of the most common, but devastating, manifestations in hepatitis E. Current therapy for HEV aims to treat symptoms. Therapy generally involves several measures, such as vitamins for adequate nutrition, albumin and plasma for supporting treatment, symptomatic treatment for cutaneous pruritus, and ursodeoxycholic acid and S-adenosylmethionine, and Traditional Chinese medicine for removing jaundice. Patients with underlying liver disease may develop liver failure. For these patients, supportive treatment is the foundation. Ribavirin has successfully been used to prevent liver transplantation. Prevention and treatment of complications are important for treatment of liver failure. Liver support devices are intended to support liver function until such time as native liver function recovers or until liver transplantation. Liver transplantation is widely considered as irreplaceable and definitive treatment for acute-on-chronic liver failure, particularly for patients who do not improve with supportive measures to sustain life.

Is hepatitis E virus an emerging problem in industrialized countries?

Hepatitis E virus (HEV) is yearly responsible for approximately 20 million infections worldwide. Although most infections occur in developing countries, HEV appears to be an emerging problem in several industrialized countries, where it is mostly associated with either traveling to an HEV endemic area or contact with pigs, which represent a major reservoir of HEV. The major risk groups for HEV infection and its ensuing complications are elderly men, pregnant women, young children, immunocompromised patients, patients with preexisting liver disease, and workers that come into close contact with HEV-infected animals. Whereas HEV mainly causes acute self-limiting infections, chronic infections may occur among immunocompromised patients (e.g., transplant recipients and human immunodeficiency virus [HIV]-infected patients). Accordingly, HEV-HIV coinfection leads to accelerated liver cirrhosis and increased mortality rates compared to HEV infection alone, which is, except during pregnancy, usually associated with only low mortality. In the Western world, the most common genotype (gt) causing HEV infection is gt 3. Ribavirin (RBV) and interferon have been used successfully for treatment of HEV, but this treatment is contraindicated in certain patient groups. Therefore, novel antiviral compounds are highly needed, especially given that viral isolates with RBV resistance have been recently identified. Moreover, eradication of HEV is hampered by long-term environmental persistence of the virus, which represents a continuous source of the virus. In 2011, the first prophylactic HEV vaccine, Hecolin, was approved in China, but it is not yet globally available. In this review, we will discuss the molecular virology of HEV, mode of transmission in industrialized countries, and potential implications for different specific patient populations.

Clinical analysis of patients suffering from chronic hepatitis B superinfected with other hepadnaviruses

To compare the clinical manifestations, laboratory examinations, and prognoses of patients with chronic hepatitis B (CHB) who were superinfected with hepatitis A virus (HAV), hepatitis C virus (HCV), hepatitis D virus (HDV), or hepatitis E virus (HEV). Two hundred and eleven patients with confirmed CHB in our hospital, a tertiary teaching hospital in China, between 2005 and 2014 were analyzed retrospectively. Among 211 patients with CHB, 35 were superinfected with HAV, 31 were superinfected with HCV, 22 were superinfected with HDV, and 53 were superinfected with HEV. We analyzed and compared the clinical features of the five groups. The tested biochemical indices and markers of liver function included serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBil), prothrombin activity (PTA), serum albumin (Alb), and the serum levels of HBV DNA. The peak values of ALT, AST, and TBil were significantly higher in all of the superinfected groups. Lower peak Alb concentration and PTA were also observed in the superinfected patients, with the exception of patients in the CHB + HAV group. The CHB + HCV, and CHB + HEV groups had higher death rates than the CHB monoinfected group, and the difference was statistically significant. Further analysis of the liver failure groups showed that the level of HBV DNA was not correlated with prognosis. The comparison of clinical outcomes revealed that CHB patients superinfected with HCV, HDV, and HEV compared with CHB monoinfection had statistically greater incidences of exacerbation of the condition and poor prognosis, whereas the patients superinfected with HAV generally had better outcomes.

Hepatitis E Virus Superinfection and Clinical Progression in Hepatitis B Patients

Hepatitis E virus (HEV) infection may cause acute hepatitis and lead to hepatic failure in developing and developed countries. We studied HEV seroprevalences in patients with hepatitis B virus (HBV) infection to understand the consequences of HEV superinfection in a Vietnamese population. This cross-sectional study was conducted from 2012 to 2013 and included 1318 Vietnamese patients with HBV-related liver diseases and 340 healthy controls. The case group included patients with acute (n = 26) and chronic hepatitis B (n = 744), liver cirrhosis (n = 160), hepatocellular carcinoma (n = 166) and patients with both liver cirrhosis and hepatocellular carcinoma (n = 222). Anti-HEV IgG and IgM antibodies were assessed in patients and controls by ELISA. HEV-RNA was identified by PCR assays and sequencing. Seroprevalences of anti-HEV IgG among hepatitis B patients and controls were 45% and 31%, respectively (adjusted P = 0.034). Anti-HEV IgM seroprevalences were 11.6% and 4.7% in patients and controls, respectively (adjusted P = 0.005). Seroprevalences were higher among the elder individuals. When stratifying for patient groups, those with liver cirrhosis had the highest anti-HEV IgG (52%) and anti-HEV IgM (19%) seroprevalences. Hepatitis B patients with current HEV infection had abnormal liver function tests compared to patients with past or without HEV infection. One HEV isolate was retrieved from a patient with both liver cirrhosis and hepatocellular carcinoma and identified as HEV genotype 3. This study indicates high prevalences of HEV infection in Vietnamese HBV patients and among healthy individuals and shows that HEV superinfection may influence the outcome and progression of HBV-related liver disease.

Epidemiology of sexually transmitted viral hepatitis in human immunodeficiency virus-positive men who have sex with men in Asia

Both human immunodeficiency virus (HIV) and viral hepatitis constitute major disease burden globally. As with other parts of the world, the HIV epidemic in Asia impacts mainly on men who have sex with men, one of the at-risk populations for sexually transmitted viral hepatitis. With the increasing availability of effective antiretroviral therapy, HIV-related mortality of people living with HIV has markedly reduced. Liver disease has become an important cause of mortality and morbidity in the HIV-infected population. With the improvement of socioeconomic conditions and availability of healthcare in Asian countries in recent years, the epidemiology of sexually transmitted viral hepatitis among HIV-positive men who have sex with men has also evolved. This review updates the epidemiology of different types of sexually transmitted viral hepatitis in this defined population in Asia.

Comparison of acute hepatitis E infection outcome in patients with and without chronic hepatitis B infection: a 10 year retrospective study in three regional hospitals in Hong Kong

BACKGROUND

Acute hepatitis E virus (HEV) infection has recently become the commonest cause of acute viral hepatitis in Hong Kong (HK) with majority of HEV belonging to genotype 4. Studies from China have shown that acute hepatitis E patients with underlying chronic hepatitis B virus (HBV) infection may have a worse outcome than those without. In India where genotype 1 is more prevalent, superinfection with hepatitis E on patients with chronic liver disease including chronic hepatitis B infection can cause liver decompensation.

OBJECTIVES

The study aims to determine the clinical outcome of acute hepatitis E infection in patients with and without chronic hepatitis B infection in HK.

STUDY DESIGN

The rates of liver failure, liver-related mortality and all-cause mortality will be compared between acute hepatitis E patients with and without chronic hepatitis B. Analysis was performed using the Statistical Package for the Social Science (SPSS version 12.0). All statistical tests were two-sided, and statistical significance was taken as p<0.05.

RESULTS

Chronic HBV carriers with acute HEV infection were found to have higher liver failure rate, liver-related mortality and all-cause mortality, but the results did not reach statistical significance. Chronic HBV carriers were found to have statistically significantly lower admission ALT level, lower day 28 serum albumin level and higher day 28 serum ALT level.

CONCLUSIONS

A prospective study with sufficient sample size is needed to confirm whether the clinical outcome of patients with chronic HBV infection is worse compared with patients who were not chronic HBV carriers.