Hepatitis E virus infection as a direct cause of neuralgic amyotrophy

Hepatitis E and diaphragmatic dysfunction: Case series and review of the literature

INTRODUCTION

The causes of diaphragmatic paresis are manifold. An association between neuralgic amyotrophy (NA) and hepatitis E virus (HEV) infection has been reported. We wondered about the prevalence of diaphragmatic disfunction and hepatitis E infection in our clinic.

METHODS

From July 1st, 2020 to August 31st, 2023, patients presenting with diaphragmatic dysfunction and simultaneous clinical symptoms of an acute NA, or a history of NA, as well as patients with previously unexplained diaphragmatic dysfunction were examined for HEV infection.

RESULTS

By August 31st, 2023, 13 patients with diaphragmatic dysfunction and HEV infection were diagnosed (4 women, 9 men). Mean age was 59 ± 10 years. Liver values were normal in all patients. The median latency to diagnosis was five months (range: 1-48 months); nine patients, 4 of them with typical symptoms of NA, presented with acute onset three patients showed bilateral diaphragmatic dysfunction. All patients had a positive IgG immunoblot. Seven patients, three with NA, had an elevated hepatitis E IgM titer and six of them also a positive IgM immunoblot. In all cases, O2C hepatitis genotype 3 was identified. In eight cases, all those with a high IgG titer >125, the O2 genotype 1 was also detected.

CONCLUSION

NA that shows involvement of the phrenic nerve resulting in diaphragmatic dysfunction and dyspnoea, may be associated with HEV infection. The observation of 13 patients with diaphragmatic dysfunctions and HEV infection within a period of three years indicates a high number of undetected HEV-associated diaphragmatic dysfunction in the population, especially in the absence of NA symptoms. Therefore, even in diaphragmatic dysfunction without NA symptoms and causative damaging event, HEV infection should be considered, as it may represent a subform of NA with only phrenic nerve involvement. Therapy of HEV-associated diaphragmatic dysfunction in the acute phase is an open question. In view of the poor prognosis for recovery, antiviral therapy should be discussed. However, no relevant data are currently available.

Hepatitis E: An update on One Health and clinical medicine

The hepatitis E virus (HEV) is one of the main causes of acute hepatitis and the de facto global burden is underestimated. HEV-related clinical complications are often undetected and are not considered in the differential diagnosis. Convincing findings from studies suggest that HEV is clinically relevant not only in developing countries but also in industrialized countries. Eight HEV genotypes (HEV-1 to HEV-8) with different human and animal hosts and other HEV-related viruses are in circulation. Transmission routes vary by genotype and location, with large waterborne outbreaks in developing countries and zoonotic food-borne infections in developed countries. An acute infection can be aggravated in pregnant women, organ transplant recipients, patients with pre-existing liver disease and immunosuppressed patients. HEV during pregnancy affects the fetus and newborn with an increased risk of vertical transmission, preterm and stillbirth, neonatal jaundice and miscarriage. Hepatitis E is associated with extrahepatic manifestations that include neurological disorders such as neuralgic amyotrophy, Guillain-Barré syndrome and encephalitis, renal injury and haematological disorders. The risk of transfusion-transmitted HEV is increasingly recognized in Western countries where the risk may be because of a zoonosis. RNA testing of blood components is essential to determine the risk of transfusion-transmitted HEV. There are currently no approved drugs or vaccines for HEV infections. This review focuses on updating the latest developments in zoonoses, screening and diagnostics, drugs in use and under development, and vaccines.

Neurological manifestations of hepatitis E virus infection: An overview

Hepatitis E virus (HEV) is an important cause of repeated waterborne outbreaks of acute hepatitis. Recently, several extrahepatic manifestations (EHMs) have been described in patients with HEV infection. Of these, neurological disorders are the most common EHM associated with HEV. The involvement of both the peripheral nervous system and central nervous system can occur together or in isolation. Patients can present with normal liver function tests, which can often be misleading for physicians. There is a paucity of data on HEV-related neurological manifestations; and these data are mostly described as case reports and case series. In this review, we analyzed data of 163 reported cases of HEV-related neurological disorders. The mechanisms of pathogenesis, clinico-demographic profile, and outcomes of the HEV-related neurological disorders are described in this article. Nerve root and plexus disorder were found to be the most commonly reported disease, followed by meningoencephalitis.

Diaphragmatic paralysis resulting in respiratory failure as a feature of hepatitis E virus-associated neuralgic amyotrophy

Hepatitis E virus (HEV)-associated neuralgic amyotrophy (NA) is often bilateral and severe, involving structures outside the brachial plexus, such as the phrenic nerves or the lumbosacral plexus. We report a case of an HEV-positive man who had presented with brachial neuritis, with significant phrenic nerve involvement, resulting in diaphragmatic paralysis requiring non-invasive ventilation. Prognosis of HEV-associated NA is often unfavourable and recovery is usually incomplete. Identifying HEV-associated NA early could potentially aid in prognostication and management planning, as clinicians and patients would be expectant of its potential features and severity. Respiratory function should be monitored in patients with HEV who suffer from NA, as diaphragmatic paralysis could potentially lead to severe respiration difficulties requiring ventilatory support.

Parsonage-Turner syndrome associated with hepatitis E infection in immunocompetent patients

Introduction The hepatitis E virus (HEV) is the leading cause of acute hepatitis around the world. In recent years, knowledge has increased concerning extrahepatic manifestations caused by HEV, including neurological manifestations such as Parsonage-Turner syndrome (PTS). PTS is characterized by severe shoulder or arm pain and patchy paresis with muscle weakness. The aim of the present study was to assess the association between HEV and PTS. Materials and Methods We reported two cases of PTS associated with HEV, which were diagnosed in a short period of time in the same village. PTS was diagnosed by physical examination and electrophysiological studies, and serology testing for IgM, low-avidity IgG, and RNA of HEV established the diagnosis of acute HEV infection. Results A 44-year-old man who presented cervicobrachial pain accompanied by paresthesia, dyspnea, and isolated derangement of liver enzymes and 57-year-old women with cervical pain radiated to upper limbs, paresthesia, and liver cytolysis, although, this patient was initially diagnosed as having drug-induced hepatitis. Finally, the diagnosis was Parsonage- Turner syndrome associated with hepatitis e virus. In both patients, symptoms were bilateral and they required hospital admission. Both consumed vegetables are grown in a local patch and the phylogenetic analysis showed genotype 3f. Then, we reviewed the literature on PTS and HEV and we found 62 previously described cases that were more likely to be men (86.20 %) with more frequent bilateral symptoms (85.71 %). Genotype 3 is the most commonly associated. Three of those cases were diagnosed in Spain. Conclusions According to our findings, HEV should be considered in patients with neuralgic amyotrophy, including those with the absence of liver cytolysis.

A Systematic Review of the Extra-Hepatic Manifestations of Hepatitis E Virus Infection

Hepatitis E virus (HEV) is a non-enveloped, positive-sense, single-stranded RNA icosahedral virus belongs to the genus Orthohepevirus within the Hepeviridae family. HEV infection can be asymptomatic, or it can cause icteric or fulminant hepatitis. Off late, there have been a number of publications reporting the extra-hepatic manifestations of HEV infection, and this systematic review is aimed at summarizing the available evidence in this regard. Two independent investigators searched PubMed, PubMed Central and Embase databases using the search string "(((hepatitis E) AND (Extrahepatic OR Extra-Hepatic))) OR ((Hepatitis E) AND (Neurology OR Cardiology OR Respiratory OR Lung OR Gastrointestinal OR musculoskeletal OR immunology OR pulmonary)) Filters: Abstract availability, English language, and Human studies". The extra-hepatic manifestations reported in each of the selected articles were classified and reported as neurological, cardiovascular, and hematological and miscellaneous manifestations. The total number of various manifestations reported in our study were n = 324. These include neurological manifestations (n = 178/324 (54.94%)), cardiovascular and hematological manifestations (n = 113/324 (34.88%)), gastro-intestinal/pancreaticobiliary manifestations (n = 24/324 (7.41%)) and other rarer manifestations involving systems such as renal (n = 4/324; 1.24%), endocrine (n = 1/324; 0.31%), dermatology (n = 1/324; 0.31%), respiratory (n = 1/324; 0.31%), muscular (n = 1/324; 0.31%) and immune system (n = 1/324; 0.31%). Thus, HEV can have extra-hepatic manifestations affecting any system of the human body. Further research is needed to elucidate the underlying pathophysiological manifestations of these extra-hepatic manifestations and to prove causal association with HEV.

Neurologic complications of acute hepatitis E virus infection

Objective

To assess the prevalence and clinical features of neurologic involvement in patients with acute hepatitis E virus (HEV) infection in Southern Switzerland.

Methods

Among 1,940 consecutive patients investigated for acute hepatitis E, we identified 141 cases of acute of HEV infection (anti-HEV immunoglobulin M and immunoglobulin G both reactive and/or HEV RNA positive) between June 2014 and September 2017. Neurologic cases were followed up for 6 months. We compared patients with and without neurologic symptoms.

Results

Neurologic symptoms occurred in 43 acute HEV cases (30.4%) and consisted of neuralgic amyotrophy (NA, n = 15, 10.6%) and myalgia (n = 28, 19.8%). All NA cases were immunocompetent. Men had higher odds (OR = 5.2, CI 1.12–24.0, p = 0.03) of developing NA after infection with HEV, and in 3 couples simultaneously infected with HEV, only men developed NA. Bilateral involvement of NA was predominant (2:1) and occurred only in men. Seven NA cases were viremic (all genotype 3), but HEV was undetectable in their CSF. In the acute phase of NA, 9 patients were treated with intravenous immunoglobulin and 4 with prednisone, reporting no side effects and improvement in pain and strength. Myalgia occurred both without (n = 16) or with (n = 12) concomitant elevated serum creatinine kinase. Seven cases with myalgia in the shoulder girdle did not have muscle weakness (“forme fruste” of NA).

Conclusions

Neurologic symptoms occurred in one-third of acute HEV infections and consisted of NA and myalgia. NA seems to occur more frequently in men infected by HEV and has a predominant (but not exclusive) bilateral involvement.

Multiphasic presentation of neuralgic amyotrophy associated with hepatitis E virus infection

BACKGROUND

The aim of this study was to further characterize the clinical phenotype of hepatitis E virus (HEV)-associated neuralgic amyotrophy (NA).

METHODS

Three patients with HEV-associated NA underwent clinical, electrodiagnostic, and ultrasound assessment.

RESULTS

In all patients, symptoms developed in several phases within a time span of 4-6 weeks, with three or more nerves involved. Symptoms were bilateral in two. In two patients, nerves of the trunk and the lower limb were affected as well. In one patient, three bouts occurred, each heralded by an increase in pain. In the other two, pain subsided quickly and nerve damage developed in two phases. Segmental enlargement with or without hourglass-like constrictions of the nerves was demonstrated by ultrasound in all.

CONCLUSIONS

The multiphasic presentation, together with the extensive multi-nerve involvement, may reflect a severe and protracted inflammation of the nerves in HEV-associated NA.

Pathological Cerebrospinal Fluid Findings in Patients With Neuralgic Amyotrophy and Acute Hepatitis E Virus Infection

There is growing evidence that hepatitis E virus (HEV) infection can present with extrahepatic manifestations including neurological disorders. Among these, neuralgic amyotrophy (NA) has been reported to occur in some industrialized countries. We investigated 35 patients with NA and a control group for markers of HEV infection. Acute HEV infection was found in NA patients only and was associated with an inflammatory response in the central nervous system. Shedding of HEV RNA into the cerebrospinal fluid and intrathecal production of anti-HEV immunoglobulin M occurred in 1 patient, suggesting that HEV is neurotropic.

Herpes zoster increased risk of neuralgic amyotrophy: a retrospective, population-based matched cohort study

Although neuralgic amyotrophy (NA) has occasionally been reported to be associated with reactivated herpes zoster, their associated risk remains unknown. The aim of this study was to assess the risk of developing NA following preceding herpes zoster. The authors used the National Health Insurance Research Database of Taiwan to select 41,548 patients with newly diagnosed herpes zoster during the period 2000 to 2010 and randomly extracted 166,192 matched control subjects. All participants in the study and control groups were followed for 3 months after the diagnosis to identify those who developed NA. Cox proportional hazards regression analyses were performed to evaluate the subsequent risk of NA. Twenty-one subjects from the group with herpes zoster (0.05%) developed NA over the 3-month period and 46 from the group without herpes zoster (0.03%). The patients with herpes zoster had a higher risk of developing NA (adjusted hazard ratio = 1.408, 95% confidence interval = 1.013-2.319, P = 0.030). In the patients with herpes zoster, female sex, age ≥ 65, hepatitis E virus (HEV), and having had a recent infectious event including pneumonia and influenza were risk factors for developing NA (adjusted HR 2.746, 1.998, 2.735, 2.016, and 1.718, respectively, all P < 0.05). Patients with herpes zoster attack have a higher risk of developing NA over a 3-month period after diagnosis, especially those who are female, age ≥ 65, HEV, or have experienced a recent infectious event or pneumonia and influenza.

Human hepatitis E virus circulation in Bulgaria: Deep Bayesian phylogenetic analysis for viral spread control in the country

Hepatitis E virus (HEV) infection in Bulgaria is endemic, as demonstrated by the seroprevalence of antibody against the virus in the general population and by the high prevalence of clinical cases registered. In this study, a deep Bayesian phylogenetic analysis has been performed to provide information on the genetic diversity and the spread of HEV genotypes in Bulgaria. Three different data sets of HEV virus was built for genotyping by the maximum likelihood method, for evolutionary rate estimated by Bayesian Markov Chain Monte Carlo approach, for demographic history investigation and for selective pressure analysis. The evolutionary rate for genotype 3e, was 351 × 10^-3 substitution/site/year (95% highest posterior density [95% HPD]: 145 × 10 ^-3 -575 × 10 ^-3 ). The root of the time to the most recent common ancestor of the Bayesian maximum clade credibility tree of HEV 3e genotype corresponded to 1965 (HPD 95% 1949-1994). The Bulgarian sequences mainly clustered in the main clade (clade A). The monophyletic clade included all Bulgarian genotype 3e sequences. The demographic history showed a slight growth from 1995 to 2000, followed by a sort of bottleneck in 2010s, a peak in 2011 and a new growth to 2015. Selection pressure analysis did not show sites under positive pressure but 64 statistically significant sites under negative selection. Molecular epidemiological surveillance by Bayesian phylogeny of HEV virus can contribute to trace the way of human infection after contact with swine source directly or heating meat improving public health control.

Hepatitis E virus as a cause of acute hepatitis acquired in Switzerland

BACKGROUND

Autochthonous hepatitis E is increasingly recognized as zoonotic infection in western countries. Serological assays have varying sensitivity and specificity.

METHODS

We implemented molecular testing to identify and characterize acute hepatitis E acquired in Switzerland.

RESULTS

Ninety-three cases of mostly symptomatic acute hepatitis E acquired in Switzerland were documented by PCR between November 2011 and December 2016. Median HEV RNA was 7.5 x 10⁴ IU/mL (range, 5.3 to 4.7 x 10⁷ IU/mL). HEV genotyping was successful in 78 patients, revealing genotype 3 in 75 and genotype 4 in three patients. Phylogenetic analyses revealed a few limited geographical and temporal clusters. Of the 91 patients with available anti-HEV IgM serology, four were negative; three of these were also IgG-negative, likely as a result of immunosuppression, and one was IgG-positive, a constellation compatible with HEV reinfection. Median age of the patients was 58 years (range, 20-80 years); 71 (76.3%) were men and 49 of these (69.0%) were ≥ 50 years old. The clinical course was particularly severe in patients with underlying chronic liver disease, with fatal outcome in two patients. Six patients (6.5%) presented with neuralgic amyotrophy.

CONCLUSIONS

Nucleic acid-based diagnosis reveals HEV as a relevant cause of acute hepatitis in Switzerland. Middle-aged and elderly men constitute the majority of symptomatic patients. Testing for HEV should be included early in the diagnostic workup of acute hepatitis and of neuralgic amyotrophy, a typical extrahepatic manifestation of HEV genotype 3 infection.

Hepatitis E virus infection

Hepatitis E virus (HEV) infection can lead to acute and chronic hepatitis as well as to extrahepatic manifestations such as neurological and renal disease; it is the most common cause of acute viral hepatitis worldwide. Four genotypes are responsible for most infection in humans, of which HEV genotypes 1 and 2 are obligate human pathogens and HEV genotypes 3 and 4 are mostly zoonotic. Until quite recently, HEV was considered to be mainly responsible for epidemics of acute hepatitis in developing regions owing to contamination of drinking water supplies with human faeces. However, HEV is increasingly being recognized as endemic in some developed regions. In this setting, infections occur through zoonotic transmission or contaminated blood products and can cause chronic hepatitis in immunocompromised individuals. HEV infections can be diagnosed by measuring anti-HEV antibodies, HEV RNA or viral capsid antigen in blood or stool. Although an effective HEV vaccine exists, it is only licensed for use in China. Acute hepatitis E is usually self-limiting and does not require specific treatment. Management of immunocompromised individuals involves lowering the dose of immunosuppressive drugs and/or treatment with the antiviral agent ribavirin.

Hepatitis E Virus Infects Neurons and Brains

Hepatitis E virus (HEV), as a hepatotropic virus, is supposed to exclusively infect the liver and only cause hepatitis. However, a broad range of extrahepatic manifestations (in particular, idiopathic neurological disorders) have been recently reported in association with its infection. In this study, we have demonstrated that various human neural cell lines (embryonic stem cell-derived neural lineage cells) induced pluripotent stem cell-derived human neurons and primary mouse neurons are highly susceptible to HEV infection. Treatment with interferon-α or ribavirin, the off-label antiviral drugs for chronic hepatitis E, exerted potent antiviral activities against HEV infection in neural cells. More importantly, in mice and monkey peripherally inoculated with HEV particles, viral RNA and protein were detected in brain tissues. Finally, patients with HEV-associated neurological disorders shed the virus into cerebrospinal fluid, indicating a direct infection of their nervous system. Thus, HEV is neurotropic in vitro, and in mice, monkeys, and possibly humans. These results challenge the dogma of HEV as a pure hepatotropic virus and suggest that HEV infection should be considered in the differential diagnosis of idiopathic neurological disorders.

Clinical phenotype and outcome of hepatitis E virus-associated neuralgic amyotrophy

OBJECTIVE

To determine the clinical phenotype and outcome in hepatitis E virus-associated neuralgic amyotrophy (HEV-NA).

METHODS

Cases of NA were identified in 11 centers from 7 European countries, with retrospective analysis of demographics, clinical/laboratory findings, and treatment and outcome. Cases of HEV-NA were compared with NA cases without evidence of HEV infection.

RESULTS

Fifty-seven cases of HEV-NA and 61 NA cases without HEV were studied. Fifty-six of 57 HEV-NA cases were anti-HEV IgM positive; 53/57 were IgG positive. In 38 cases, HEV RNA was recovered from the serum and in 1 from the CSF (all genotype 3). Fifty-one of 57 HEV-NA cases were anicteric; median alanine aminotransferase 259 IU/L (range 12-2,961 IU/L); in 6 cases, liver function tests were normal. HEV-NA cases were more likely to have bilateral involvement (80.0% vs 8.6%, p < 0.001), damage outside the brachial plexus (58.5% vs 10.5%, p < 0.01), including phrenic nerve and lumbosacral plexus injury (25.0% vs 3.5%, p = 0.01, and 26.4% vs 7.0%, p = 0.001), reduced reflexes (p = 0.03), sensory symptoms (p = 0.04) with more extensive damage to the brachial plexus. There was no difference in outcome between the 2 groups at 12 months.

CONCLUSIONS

Patients with HEV-NA are usually anicteric and have a distinct clinical phenotype, with predominately bilateral asymmetrical involvement of, and more extensive damage to, the brachial plexus. Involvement outside the brachial plexus is more common in HEV-NA. The relationship between HEV and NA is likely to be causal, but is easily overlooked. Patients presenting with NA should be tested for HEV, irrespective of liver function test results. Prospective treatment/outcome studies of HEV-NA are warranted.

Parsonage-Turner syndrome due to autochthonous acute genotype 3f hepatitis E virus infection in a nonimmunocompromised 55-year-old patient

Hepatitis E virus (HEV) infection is an emerging autochthonous disease in industrialized countries. Extra-hepatic manifestations, in particular neurologic manifestations, have been reported in HEV infection. Only a few cases of hepatitis E-associated Parsonage-Turner syndrome have been reported, and HEV genotypes were rarely determined. Here, we report the case of a Parsonage-Turner syndrome associated with an acute autochthonous HEV infection in a 55-year-old immunocompetent patient. HEV genomic RNA was detected in serum and cerebrospinal fluid samples (CSF), and molecular phylogenetic analysis of HEV was performed. The interest of this case lies in its detailed description notably the molecular analysis of HEV RNA isolated from serum and CSF. HEV infection should be considered in diagnostic investigations of neurologic manifestations associated with liver function perturbations.

Neuralgic amyotrophy triggered by hepatitis E virus: a particular phenotype

The neuralgic amyotrophy may be of difficult diagnosis, due to phenotypic variability, with different initial presentations (upper plexus multiple mononeuropathy, lumbosacral involvement, distal reached, phrenic involvement). To date, there is little guidance on these patients' therapeutic management, especially those for which neuralgic amyotrophy is triggered by hepatitis E virus (HEV-NA). The study aims to identify specific features that characterize patients bearing the neuralgic amyotrophy triggered by HEV. We first describe a new case report of HEV-neuralgic amyotrophy, with delayed diaphragmatic reach. Then, the literature was searched for reports of HEV-NA (n = 39), and neuralgic amyotrophy with phrenic paresis (n = 42) from 1999 to June 2016. Relevant data were retrieved, analyzed and compared with the parameters of idiopathic neuralgic amyotrophy (n = 199) of the largest cohort, described by Van Alfen and Van Engelen in 2006. Compared to the published cohort, HEV-NA patients were more likely to be men (M/F 34/5 vs. 136/63, p = 0.017), with more frequent bilateral symptoms (86.8% cases vs. 28.5%, p < 0.0001) as well as phrenic paresis (18.0 vs. 6.6%, p = 0.028). The clinical improvement is poor, with 15.6% of cases with remission only. A particular phenotype characteristic of the HEV-induced neuralgic amyotrophy has arisen. Our findings call for action in validating the above-mentioned features that illustrate the HEV-NA cases as an early diagnosis would prevent complications, especially the phrenic damage often associated with a worse functional outcome.

Mutagenic Effects of Ribavirin on Hepatitis E Virus-Viral Extinction versus Selection of Fitness-Enhancing Mutations

Hepatitis E virus (HEV), an important agent of viral hepatitis worldwide, can cause severe courses of infection in pregnant women and immunosuppressed patients. To date, HEV infections can only be treated with ribavirin (RBV). Major drawbacks of this therapy are that RBV is not approved for administration to pregnant women and that the virus can acquire mutations, which render the intra-host population less sensitive or even resistant to RBV. One of the proposed modes of action of RBV is a direct mutagenic effect on viral genomes, inducing mismatches and subsequent nucleotide substitutions. These transition events can drive the already error-prone viral replication beyond an error threshold, causing viral population extinction. In contrast, the expanded heterogeneous viral population can facilitate selection of mutant viruses with enhanced replication fitness. Emergence of these mutant viruses can lead to therapeutic failure. Consequently, the onset of RBV treatment in chronically HEV-infected individuals can result in two divergent outcomes: viral extinction versus selection of fitness-enhanced viruses. Following an overview of RNA viruses treated with RBV in clinics and a summary of the different antiviral modes of action of this drug, we focus on the mutagenic effect of RBV on HEV intrahost populations, and how HEV is able to overcome lethal mutagenesis.