Acute hepatitis E virus superinfection increases mortality in patients with cirrhosis

Hepatitis E Virus (HEV) Infection Among Immunocompromised Individuals: A Brief Narrative Review

Hepatitis E virus (HEV) is a single-stranded positive-sense RNA virus that belongs to Hepeviridae family. HEV is the most common cause of acute viral hepatitis worldwide. According to the World Health Organization (WHO), there are estimated 20 million HEV infections worldwide every year, leading to estimated 3.3 million symptomatic cases of HEV infection. The WHO estimates that HEV infection caused approximately 44,000 deaths in 2015, which represents 3.3% of mortality rates due to viral hepatitis. In low-income (LI) countries and lower-middle-income (LMI) countries, HEV is a waterborne infection induced by HEV genotype (gt) 1 and HEV gt 2 that cause large outbreaks and affect young individuals with a high mortality rate in pregnant women from South Asian countries and patients with liver diseases. HEV gt 3, HEV gt 4, and HEV gt 7 are responsible for sporadic infections with zoonotic transmission mainly through the consumption of raw or undercooked meat from different animals. Acute HEV infection is relatively asymptomatic or mild clinical form, in rare cases the disease can be moderate/severe clinical forms and result in fulminant hepatitis or acute liver failure (ALF). Furthermore, HEV infection is associated with extrahepatic manifestations, including renal and neurological clinical signs and symptoms. Pregnant women, infants, older people, immunocompromised individuals, patients with comorbidities, and workers who come into close contact with HEV-infected animals are recognized as major risk groups for severe clinical form of HEV infection and fatal outcome. Chronic HEV infection can occur in immunocompromised individuals with the possibility of progression to cirrhosis.

The pressing need for a global HEV vaccine

Based on the worldwide distribution of hepatitis E virus (HEV) and its ability to cause major epidemics in low-income countries, the global availability of a HEV vaccine is a pressing clinical need. Populations at risk of severe forms of the infection are well characterised: patients with chronic liver disease - at risk of liver failure; pregnant women - at risk of fulminant hepatitis or obstetrical complications; and immunosuppressed patients, particularly those with solid organ transplants - at risk of chronic hepatitis and rapid progression to cirrhosis. Only one hepatitis E vaccine is presently being manufactured. It has been proven to be effective and safe. However, its accessibility, as well as data on its long-term efficacy and the duration of protection it confers, are limited. While individuals considered to be at risk of severe infection appear to be ideal targets for the vaccine, its effectiveness and tolerability have not yet been studied in populations with chronic liver disease and immunosuppressed patients. Hepatitis E vaccination could also play an important role in controlling outbreaks in large waterborne epidemics. Clinical trials on these populations are needed.

Prevalence, incidence, and outcomes of hepatitis E virus coinfection in patients with chronic hepatitis C

This study aimed to elucidate the anti-hepatitis E virus (HEV) immunoglobulin G (IgG) prevalence and incidence of seroconversion and seroreversion as well as its risk factors and to analyze the clinical outcomes of HEV and hepatitis C virus (HCV) coinfected patients compared to those of HCV-monoinfected patients. We prospectively enrolled 502 viremic HCV patients with paired plasma samples (at intervals of ≥ 12 months) from 5 tertiary hospitals. Anti-HEV IgG positivity was tested using the Wantai ELISA kit in all paired samples. Mean age was 58.2 ± 11.5 years old, 48.2% were male, 29.9% of patients had liver cirrhosis, and 9.4% of patients were diagnosed with hepatocellular carcinoma (HCC). The overall prevalence of anti-HEV IgG positivity at enrollment was 33.3%, with a higher prevalence in males and increasing prevalence according to the subject's age. During the 916.4 person-year, the HEV incidence rate was 0.98/100 person-years (9/335, 2.7%). Hepatic decompensation or liver-related mortality was not observed. There were six seroreversion cases among 172 anti-HEV-positive patients (1.22/100 person-years). In conclusion, approximately one-third of the adult Korean chronic HCV patients were anti-HEV IgG positive. The HEV incidence rate was 1 in 100 persons per year, without adverse hepatic outcomes or mortality.

Challenges in Diagnosis and Therapeutic Approach of Acute on Chronic Liver Failure-A Review of Current Evidence

Acute-on-chronic liver failure (ACLF) is a syndrome characterized by acute and severe decompensation of chronic liver disease (CLD) correlated with multiple organ failure, poor prognosis, and increased mortality. In 40-50% of ACLF cases, the trigger is not recognized; for many of these patients, bacterial translocation associated with systemic inflammation is thought to be the determining factor; in the other 50% of patients, sepsis, alcohol consumption, and reactivation of chronic viral hepatitis are the most frequently described trigger factors. Other conditions considered precipitating factors are less common, including acute alcoholic hepatitis, major surgery, TIPS insertion, or inadequate paracentesis without albumin substitution. Host response is likely the primary factor predicting ACLF severity and prognosis, the host immune response having a particular significance in this syndrome, together with the inflammatory cascade. The management of ACLF includes both the prevention of the precipitating factors that lead to acute liver decompensation and the support of vital functions, the prevention and management of complications, the estimation of prognosis, and the opportunity for liver transplantation.

A new dyslipidemia-based scoring model to predict transplant-free survival in patients with hepatitis E-triggered acute-on-chronic liver failure

BACKGROUND/AIMS

Hepatitis E virus (HEV)-triggered acute-on-chronic liver failure (ACLF) has unacceptably high short-term mortality. However, it is unclear whether the existing predictive scoring models are applicable to evaluate the prognosis of HEV-triggered ACLF.

METHODS

We screened datasets of patients with HEV-triggered ACLF from a regional tertiary hospital for infectious diseases in Shanghai, China, between January 2011 and January 2021. Clinical and laboratory parameters were recorded and compared to determine a variety of short-term mortality risk factors, which were used to develop and validate a new prognostic scoring model.

RESULTS

Out of 4952 HEV-infected patients, 817 patients with underlying chronic liver disease were enrolled in this study. Among these, 371 patients with HEV-triggered ACLF were identified and allocated to the training set (n = 254) and test set (n = 117). The analysis revealed that hepatic encephalopathy (HE), ascites, triacylglycerol and apolipoprotein A (apoA) were associated with 90-day mortality (P < 0.05). Based on these significant indicators, we designed and calculated a new prognostic score = 0.632 × (ascites: no, 1 point; mild to moderate, 2 points; severe, 3 points) + 0.865 × (HE: no, 1 point; grade 1-2, 2 points; grade 3-4, 3 points) - 0.413 × triacylglycerol (mmol/L) - 2.171 × apoA (g/L). Compared to four well-known prognostic models (MELD score, CTP score, CLIF-C OFs and CLIF-C ACLFs), the new scoring model is more accurate, with the highest auROCs of 0.878 and 0.896, respectively, to predict 28- and 90-day transplantation-free survival from HEV-triggered ACLF. When our model was compared to COSSH ACLF IIs, there was no significant difference. The test data also demonstrated good concordance.

CONCLUSIONS

This study is one of the first to address the correlation between hepatitis E and serum lipids and provides a new simple and efficient prognostic scoring model for HEV-triggered ACLF.

Hepatitis E Virus Infections: Epidemiology, Genetic Diversity, and Clinical Considerations

According to the World Health Organization, approximately 20 million people worldwide are infected annually with the hepatitis E virus (HEV). There are four main genotypes of HEV. Genotype 1 and genotype 2 are common in developing countries and are transmitted by contaminated water from a fecal-oral route. Genotype 3 and genotype 4 are common in developed countries and can lead to occasional transmission to humans via undercooked meat. Hepatitis E virus 1 and HEV3 can lead to fulminant hepatitis, and HEV3 can lead to chronic hepatitis and cirrhosis in immunocompromised patients. The majority of patients with HEV infection are asymptomatic and usually have spontaneous viral clearance without treatment. However, infection in immunocompromised individuals can lead to chronic HEV infection. Both acute and chronic HEV infections can have extrahepatic manifestations. No specific treatment is required for acute HEV infection, no treatment has been approved in chronic infection, and no HEV vaccine has been approved by the (United States) Food and Drug Administration. This review focuses on the molecular virology (HEV life cycle, genotypes, model systems, zoonosis), pathogenesis, clinical manifestation, and treatment of chronic HEV infection, especially in immunocompromised patients, to provide clinicians a better understanding of the global distribution of these infections and the significant effect they can have on immunocompromised patients.

Hepatitis E Virus Research in Brazil: Looking Back and Forwards

Hepatitis E virus (HEV) has emerged as a public health concern in Brazil. From the first identification and characterization of porcine and human HEV-3 strains in the 2000s, new HEV subtypes have been identified from animal, human, and environmental isolates. As new potential animal reservoirs have emerged, there is a need to compile evidence on the zoonotic dissemination of the virus in animal hosts and the environment. The increasing amount of seroprevalence data on sampled and randomly selected populations must be systematically retrieved, interpreted, and considered under the One Health concept. This review focused on HEV seroprevalence data in distinct animal reservoirs and human populations reported in the last two decades. Furthermore, the expertise with experimental infection models using non-human primates may provide new insights into HEV pathogenesis, prevention, and environmental surveillance.

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.

Inhibition of Hepatitis E Virus Replication by Novel Inhibitor Targeting Methyltransferase

Hepatitis E Virus (HEV) is a quasi-enveloped virus having a single-stranded, positive-sense RNA genome (~7.2 kb), flanked with a 5′ methylated cap and a 3′ polyadenylated tail. The HEV open reading frame 1 (ORF1) encodes a 186-kDa polyprotein speculated to get processed and produce Methyltransferase (MTase), one of the four essential replication enzymes. In this study, we report the identification of the MTase inhibitor, which may potentially deplete its enzymatic activity, thus causing the cessation of viral replication. Using in silico screening through docking, we identified ten putative compounds, which were tested for their anti-MTase activity. This resulted in the identification of 3-(4-Hydroxyphenyl)propionic acid (HPPA), with an IC₅₀ value of 0.932 ± 0.15 μM, which could be perceived as an effective HEV inhibitor. Furthermore, the compound was tested for inhibition of HEV replication in the HEV culture system. The viral RNA copies were markedly decreased from ~3.2 × 10⁶ in untreated cells to ~4.3 × 10^2.8 copies in 800 μM HPPA treated cells. Therefore, we propose HPPA as a potential drug-like inhibitor against HEV-MTase, which would need further validation through in vivo analysis using animal models and the administration of Pharmacokinetic and Pharmacodynamic (PK/PD) studies.

Similarities, differences, and possible interactions between hepatitis E and hepatitis C viruses: Relevance for research and clinical practice

Hepatitis E virus (HEV) and hepatitis C virus (HCV) are both RNA viruses with a tropism for liver parenchyma but are also capable of extrahepatic manifestations. Hepatitis E is usually a viral acute fecal-oral transmitted and self-limiting disease presenting with malaise, jaundice, nausea and vomiting. Rarely, HEV causes a chronic infection in immunocompromised persons and severe fulminant hepatitis in pregnant women. Parenteral HCV infection is typically asymptomatic for decades until chronic complications, such as cirrhosis and cancer, occur. Despite being two very different viruses in terms of phylogenetic and clinical presentations, HEV and HCV show many similarities regarding possible transmission through organ transplantation and blood transfusion, pathogenesis (production of antinuclear antibodies and cryoglobulins) and response to treatment with some direct-acting antiviral drugs. Although both HEV and HCV are well studied individually, there is a lack of knowledge about coinfection and its consequences. The aim of this review is to analyze current literature by evaluating original articles and case reports and to hypothesize some interactions that can be useful for research and clinical practice.