Incidence, predictors and prognosis of genotype 4 hepatitis E related liver failure: A tertiary nested case-control study

Systematic Evaluation of Guidelines for the Diagnosis and Treatment of Hepatitis E Virus Infection

Background and Aims

The hepatitis E virus (HEV) is a zoonotic disease, and infection with HEV in humans primarily causes acute infections and can progress to chronic manifestation in immunocompromised individuals. Over the past decade, guidelines for diagnosing and treating HEV infection have been developed. This study aimed to systematically assess the quality of current guidelines for diagnosing and treating HEV infection, and we analyzed the differences in guideline quality and primary recommendations and explored possible reasons for these differences.

Methods

Guidelines published between 2013 and 2022 were searched, and studies were identified using selection criteria. The study assessed the quality of the included guidelines using the Appraisal of Guidelines for Research and Evaluation tool, extracted the primary recommendations in the guidelines, determined the highest level of evidence supporting the recommendations, and reclassified the evidence using the Oxford Centre for Evidence-Based Medicine grading system.

Results

Seven guidelines were included in the final analysis. The quality of the guidelines varied widely. The discrepancies may have been caused by the lack of external experts, the failure to consider influencing factors in guideline application, and the lack of consideration of the public's opinion. Analysis of the heterogeneity in primary recommendations revealed differences in algorithms for managing chronic HEV infection, the dosage of ribavirin, and a low level of evidence supporting the primary recommendations.

Conclusions

Guideline quality and primary recommendations vary considerably. Refinement by guideline developers and researchers would facilitate updating and applying guidelines for diagnosing and treating HEV infection.

Deregulation of immune response contributing to fulminant hepatitis in HEV infected pregnant women

Hepatitis E virus (HEV) infection in pregnant women is associated with a wide spectrum of adverse consequences for both mother and fetus. The high mortality in this population appears to be associated with hormonal changes and consequent immunological changes. This study conducted an analysis of immune responses in pregnant women infected with HEV manifesting varying severity. Data mining analysis of the GSE79197 was utilized to examine differentially biological functions in pregnant women with HEV infection (P-HEV) versus without HEV infection (P-nHEV), P-HEV progressing to ALF (P-ALF) versus P-HEV, and P-HEV versus non-pregnant women with HEV infection (nP-HEV). We found cellular response to interleukin and immune response-regulating signalings were activated in P-HEV compared with P-nHEV. However, there was a significant decrease of immune responses, such as T cell activation, leukocyte cell-cell adhesion, regulation of lymphocyte activation, and immune response-regulating signaling pathway in P-ALF patient than P-HEV patient. Compared with nP-HEV, MHC protein complex binding function was inhibited in P-HEV. Further microRNA enrichment analysis showed that MAPK and T cell receptor signaling pathways were inhibited in P-HEV compared with nP-HEV. In summary, immune responses were activated during HEV infection while being suppressed when developing ALF during pregnancy, heightening the importance of immune mediation in the pathogenesis of severe outcome in HEV infected pregnant women.

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.

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.

Review of clinical characteristics, immune responses and regulatory mechanisms of hepatitis E-associated liver failure

Hepatitis E virus (HEV) is the most common cause of acute liver failure (LF) and one of the most common factors causing acute injury in acute-on-chronic LF (ACLF). When HEV-related LF occurs, a series of changes take place in both the intrahepatic environment and extrahepatic microenvironment. The changed types and distribution of immune cells (infiltrating macrophages and increased lymphocytes) in liver tissue, as well the increased proinflammatory cytokines and chemokines in the blood, indicate that the occurrence and progression of HEV-related LF are closely related to immune imbalance. The clinical features and immune reaction in the body during HEV-related acute LF (ALF) and ACLF are complicated. This review highlights recent progress in elucidating the clinical manifestations of HEV-associated ALF and ACLF and discusses the corresponding systemic immune changes and possible regulatory mechanisms.

The diagnostic and prognostic value of serum exosome-derived carbamoyl phosphate synthase 1 in HEV-related acute liver failure patients

BACKGROUND

Early diagnosis and prognosis evaluation are of great significance to HEV-related acute liver failure (HEV-ALF) patients METHODS: We collected serum samples from 200 health controls (HCs), 200 patients with acute hepatitis E (AHE) and 200 HEV-ALF patients to evaluate serum exosome-derived carbamoyl phosphate synthase 1 (CPS1) levels and determine its diagnostic and prognostic value.

RESULTS

The exosome-derived CPS1 levels in the HEV-ALF group were significantly higher than those in the AHE and HCs groups. The AUC of exosome-derived CPS1 to predict the occurrence of HEV-ALF was 0.850 (0.811-0.883). Both logistical regression and orthogonal partial least squares discriminant analysis (OPLS-DA) showed that exosome-derived CPS1 is independent risk factor for HEV-ALF. The exosome-derived CPS1 levels were positively correlated with organ failure, and the outcomes in HEV-ALF patients. The exosome-derived CPS1 levels in the worsening group were significantly higher than those in the fluctuating and the improving groups. The AUC of serum exosome-derived CPS1 to predict 30-day mortality was 0.829 (0.770-0.879), which was significantly greater than that of the Child-Pugh, KCH, and MELD model.

CONCLUSIONS

The level of serum exosome-derived CPS1 might serve as promising diagnostic and prognostic biomarker for HEV-ALF patients, which may provide better guidance for the diagnosis, prognosis and treatment of HEV-ALF patients. This article is protected by copyright. All rights reserved.

Prevalence and clinical features of hepatitis E virus infection in pregnant women: A large cohort study in Inner Mongolia, China

BACKGROUND AND AIM

Hepatitis E virus (HEV) infection causes severe maternal and fetal outcomes in pregnant women. These patients are exclusively from resource-limited regions with genotype 1 HEV infection, but not from western countries with genotype 3 prevalence. Since the circulating strains in China have evolved from the waterborne genotype 1 to the zoonotic genotype 4 HEV in the past decades, this study aims to evaluate the prevalence and clinical features of HEV infection in a large cohort of pregnant women in Inner Mongolia, China.

METHODS

A total of 3278 pregnant women who visited the Inner Mongolia Maternal and Child Care hospital during 2018 were enrolled. Serum samples were examined for anti-HEV IgG and anti-HEV IgM antibodies using ELISA. Demographic information, results of clinical biochemical tests, maternal and neonatal outcomes were collected.

RESULTS

Among the recruited 3278 pregnant women, 6.0% were anti-HEV IgG antibody positive, 0.3% were anti-HEV IgM antibody positive and 0.3% were positive for both anti-HEV IgG and anti-HEV IgM antibodies. HEV viral RNA was not detected. Pregnant women with recent/ongoing HEV infection indicated by anti-HEV IgM positivity have slightly higher ALT level, and potential risk of developing hyperlipidemia, preterm delivery and neonatal jaundice.

CONCLUSIONS

These findings indicated that HEV infection is associated with a possible increase in adverse maternal, fetal and neonatal outcomes in our cohort. Thus, the burden of HEV infection in pregnant women in China appears distinct from resource-limited regions and western countries. Nevertheless, future studies are required to confirm and extend our findings.

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.

The histologic presentation of hepatitis E reflects patients' immune status and pre-existing liver condition

Infection with the hepatitis E virus (HEV) is one of the main causes of acute hepatitis worldwide. Given that, the histopathology of hepatitis E is relatively poorly characterized, and it is unclear what exactly determines its remarkable variability. The aim of our study was a systematic analysis of hepatitis E histology, especially with regard to the clinical setting. Fifty-two liver samples (48 biopsies, 1 liver explant, 3 autopsy livers) from 41 patients with molecularly proven hepatitis E (28 HEV genotype (gt) 3, three gt 1, one gt 4 and 9 undetermined gt) were systematically evaluated for 33 histopathologic features. Following one approach, the biopsies were assigned to one of five generic histologic patterns. In another approach, they were subjected to hierarchical clustering. We found that 23/41 (56%) patients were immunocompromised, whereas 18 (44%) had no known immunosuppression. Five patients (12%) had pre-existing liver disease (LD). The histopathologic spectrum ranged from almost normal to acute, chronic, and steato-hepatitis to subtotal necrosis, and was thus distributed across all five generic patterns. Hierarchical clustering, however, identified three histopathologic clusters (C1-C3), which segregated along the immune status and pre-existing LD: C1 comprised mostly patients with pre-existing LD; histology mainly reflected the respective LD without pointing to the additional hepatitis E. C2 comprised mostly immunocompetent patients; histology mainly displayed florid hepatitis. C3 comprised mostly immunocompromised patients; histology mainly displayed smoldering hepatitis. Accordingly, C1-C3 differed markedly with respect to their clinical and histopathologic differential diagnoses. Hierarchical clustering suggests three groups with distinct histopathologies, indicating biologically different manifestations of hepatitis E. The association of histopathologic changes with the patient's immune status and pre-existing LD plausibly explains the diversity of hepatitis E histopathology, and suggests that these factors are the crucial underlying determinants. We expect our results to improve patient management by guiding the clinico-pathologic diagnosis of hepatitis E.

Clinical and virologic features of hepatitis E virus infection at a university hospital in Japan between 2000 and 2019

The clinical and virologic features of hepatitis E virus (HEV) infection seem to vary among regions even in developed countries. However, we have little information on the diversity of HEV infection. Here, we investigated the characteristics of 26 patients in our hospital located in Tochigi prefecture, 90 km north of Tokyo, between 2000 and 2019. The reported number of patients with acute hepatitis E is increasing in Japan because measurement of IgA-class anti-HEV antibody was commercially available from 2011. In contrast, the numbers at our hospital were 1.5/y and 1.0/y in 2000 to 2011 and 2012 to 2019, respectively. This is attributed to the fact that we have been investigating HEV as a cause of unknown hepatitis before 2011. Among isolated HEV subgenotypes, including 3a, 3b, 4b, 4c, and 4d, all three patients with subgenotype 4c infection presented acute liver failure. Four HEV strains shared more than or equal to 99% identity within the 412-nucleotide partial sequence, in which the time and place of HEV infection varied, except for one intrafamilial infection. In addition, some strains were similar to HEV strains isolated far from Tochigi prefecture. In conclusion, the number of patients with acute hepatitis E was not increasing at Jichi Medical University Hospital and some strains were found to circulate in Japan.

Th1/Th2 Cells and Associated Cytokines in Acute Hepatitis E and Related Acute Liver Failure

Background and Aims

The involvement of cellular immunity in the development of hepatitis E virus (HEV) infection is rare. We aimed to study the roles of viral load and Th cell responses in acute hepatitis E (AHE) and HEV-related acute liver failure (HEV-ALF).

Methods

We evaluated viral load and Th1/Th2 cytokine levels in 34 patients with HEV infection, including 17 each with AHE or HEV-ALF. Seventeen healthy controls (HCs) were also included who were negative for anti-HEV IgM and IgG.

Results

There was no significant difference in viral load and HEV RNA in the AHE and HEV-ALF groups (both P > 0.05). The Th lymphocyte levels (CD3+, CD4+) in the AHE and HEV-ALF groups were significantly higher than those in the HC group (both P < 0.05), but there was no significant difference between the AHE and HEV-ALF groups (P > 0.05). Both IFN-γ and IL-10 showed gradual upward trend from the HC group to the AHE (both P < 0.01), but IFN-γ showed a sharp downward trend from the AHE group to the HEV-ALF group (P < 0.01) and IL-4 showed gradual upward trend from the AHE group to the HEV-ALF group (P < 0.01).There was no significant difference in Th1 and Th2 cytokines between the HEV RNA(+) group and HEV RNA(-) group (all P > 0.05). Th2 bias was observed from the AHE (ratio = 58.65) to HEV-ALF (ratio = 1.20) groups. The level of IFN-γ was associated with the outcome of HEV-ALF patients.

Conclusions

HEV viral load was not associated with aggravation of AHE, and the HEV-ALF patients showed significant Th2 bias, which may be involved in the aggravation of AHE.

Altered faecal microbiota on the expression of Th cells responses in the exacerbation of patients with hepatitis E infection

Fulminant hepatitis E may lead to acute liver failure (ALF). Perturbations of intestinal microbiota are related to severe liver disease. To study the correlations between faecal microbiota and the occurrence and exacerbation of hepatitis E virus (HEV) infection, we characterized 24 faecal samples from 12 patients with acute hepatitis E (AHE) and 12 patients with HEV-ALF using high-throughput sequencing. We found both the alpha and beta diversity indices showed no significant differences between the AHE and HEV-ALF groups. Several predominant taxa were significantly different between the AHE and HEV-ALF groups. Most notably, the HEV-ALF group had increased levels of Gammaproteobacteria, Proteobacteria, Xanthomonadceae and Stenotrophomonas, but reduced levels of Firmicutes, Streptococcus, Subdoligranulum and Lactobacillus, compared with the AHE group. The levels of Lactobacillaceae and Gammaproteobacteria could be used to distinguish patients with HEV-ALF from those with AHE. In addition, the level of Th lymphocytes was significantly lower in the HEV-ALF group than in the AHE group. The relative abundances of Lactobacillaceae and Gammaproteobacteria were positively correlated with Th lymphocytes, serum international normalized ratio (INR) and hepatic encephalopathy severity. Moreover, surviving patients had higher levels of Lactobacillus mucosae than deceased patients. Our study demonstrated that the presence of altered faecal microbiota is associated with exacerbation of HEV infection; this finding may be useful for exploring the interactions among faecal microbiota, immune responses, mechanisms of infection and progression in patients with HEV, as well as for the development of novel diagnostic and therapeutic strategies.

Swine hepatitis E virus: Cross-species infection, pork safety and chronic infection

Swine hepatitis E virus (swine HEV) belongs to the species Orthohepevirus A within the genus Orthohepevirus in the family Hepeviridae. Four different genotypes of swine HEV within the species Orthohepevirus A have been identified so far from domesticated and wild swine population: genotypes 3 (HEV-3) and 4 (HEV-4) swine HEVs are zoonotic and infect humans, whereas HEV-5 and HEV-6 are only identified from swine. As a zoonotic agent, swine HEV is an emerging public health concern in many industrialized countries. Pigs are natural reservoir for HEV, consumption of raw or undercooked pork is an important route of foodborne HEV transmission. Occupational risks such as direct contact with infected pigs also increase the risk of HEV transmission in humans. Cross-species infection of HEV-3 and HEV-4 have been documented under experimental and natural conditions. Both swine HEV-3 and swine HEV-4 infect non-human primates, the surrogates of man. Swine HEV, predominantly HEV-3, can establish chronic infection in immunocompromised patients especially in solid organ transplant recipients. The zoonotic HEV-3, and to lesser extent HEV-4, have also been shown to cause neurological diseases and kidney injury. In this review, we focus on the epidemiology of swine HEV, host and viral determinants influencing cross-species HEV infection, zoonotic infection and its associated pork safety concern, as well as swine HEV-associated chronic infection and neurological diseases.