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1.
Am J Hum Genet ; 111(6): 1018-1034, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38749427

RESUMEN

Evolutionary changes in the hepatitis B virus (HBV) genome could reflect its adaptation to host-induced selective pressure. Leveraging paired human exome and ultra-deep HBV genome-sequencing data from 567 affected individuals with chronic hepatitis B, we comprehensively searched for the signatures of this evolutionary process by conducting "genome-to-genome" association tests between all human genetic variants and viral mutations. We identified significant associations between an East Asian-specific missense variant in the gene encoding the HBV entry receptor NTCP (rs2296651, NTCP S267F) and mutations within the receptor-binding region of HBV preS1. Through in silico modeling and in vitro preS1-NTCP binding assays, we observed that the associated HBV mutations are in proximity to the NTCP variant when bound and together partially increase binding affinity to NTCP S267F. Furthermore, we identified significant associations between HLA-A variation and viral mutations in HLA-A-restricted T cell epitopes. We used in silico binding prediction tools to evaluate the impact of the associated HBV mutations on HLA presentation and observed that mutations that result in weaker binding affinities to their cognate HLA alleles were enriched. Overall, our results suggest the emergence of HBV escape mutations that might alter the interaction between HBV PreS1 and its cellular receptor NTCP during viral entry into hepatocytes and confirm the role of HLA class I restriction in inducing HBV epitope variations.


Asunto(s)
Virus de la Hepatitis B , Mutación , Transportadores de Anión Orgánico Sodio-Dependiente , Simportadores , Humanos , Virus de la Hepatitis B/genética , Transportadores de Anión Orgánico Sodio-Dependiente/genética , Transportadores de Anión Orgánico Sodio-Dependiente/metabolismo , Simportadores/genética , Simportadores/metabolismo , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Hepatitis B Crónica/virología , Hepatitis B Crónica/genética , Genoma Viral , Antígenos de Superficie de la Hepatitis B/genética , Epítopos de Linfocito T/genética , Epítopos de Linfocito T/inmunología , Genómica/métodos , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/metabolismo
2.
Hepatology ; 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38079352

RESUMEN

BACKGROUND AND AIMS: The clinical spectrum of human infection by HEV ranges from asymptomatic to severe acute hepatitis. Furthermore, HEV can cause diverse neurological manifestations, especially Parsonage-Turner syndrome. Here, we used a large-scale human genomic approach to search for genetic determinants of severe clinical presentations of HEV infection. APPROACH AND RESULTS: We performed whole genome sequencing in 3 groups of study participants with PCR-proven acute HEV infection: (1) 24 patients with symptomatic acute hepatitis E; (2) 12 patients with HEV-associated Parsonage-Turner syndrome; and (3) 16 asymptomatic blood donors (controls). For variant calling and annotation, we used GATK4 best practices followed by Variant Effect Predictor (VEP) and Annovar. For variant classification, we implemented the American College of Medical Genetics and Genomics/Association for Molecular Pathology Bayesian classification framework in R. Variants with a probability of pathogenicity >0.9 were considered damaging. We used all genes with at least 1 damaging variant as input for pathway enrichment analyses.We observed a significant enrichment of type I interferon response pathways in the symptomatic hepatitis group: 10 out of 24 patients carried a damaging variant in one of 9 genes encoding either intracellular viral sensors ( IFIH1 , DDX58 , TLR3 , POLR3B , POLR3C ) or other molecules involved in type I interferon response [interferon regulatory factor 7 ( IRF7 ), MYD88 , OAS3 , GAPDH ]. We did not find any enriched pathway in the Parsonage-Turner syndrome group or in the controls. CONCLUSIONS: Our results highlight the essential role of type I interferon in preventing symptomatic acute hepatitis E.

3.
Proc Natl Acad Sci U S A ; 120(52): e2307423120, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38109552

RESUMEN

Hepatitis E virus (HEV) is a major cause of acute hepatitis worldwide. As the other positive-strand RNA viruses, it is believed to replicate its genome in a membrane-associated replication complex. However, current understanding of the host factors required for productive HEV infection is limited and the site as well as the composition of the HEV replication complex are still poorly characterized. To identify host factors required for HEV RNA replication, we performed a genome-wide CRISPR/Cas9 screen in permissive human cell lines harboring subgenomic HEV replicons allowing for positive and negative selection. Among the validated candidates, Ras-related early endosomal protein Rab5A was selected for further characterization. siRNA-mediated silencing of Rab5A and its effectors APPL1 and EEA1, but not of the late and recycling endosome components Rab7A and Rab11A, respectively, significantly reduced HEV RNA replication. Furthermore, pharmacological inhibition of Rab5A and of dynamin-2, required for the formation of early endosomes, resulted in a dose-dependent decrease of HEV RNA replication. Colocalization studies revealed close proximity of Rab5A, the HEV ORF1 protein, corresponding to the viral replicase, as well as HEV positive- and negative-strand RNA. In conclusion, we successfully exploited CRISPR/Cas9 and selectable subgenomic replicons to identify host factors of a noncytolytic virus. This approach revealed a role for Rab5A and early endosomes in HEV RNA replication, likely by serving as a scaffold for the establishment of functional replication complexes. Our findings yield insights into the HEV life cycle and the virus-host interactions required for productive infection.


Asunto(s)
Virus de la Hepatitis E , Hepatitis E , Humanos , Virus de la Hepatitis E/genética , Sistemas CRISPR-Cas , Endosomas/genética , Endosomas/metabolismo , Replicación Viral/genética , ARN Viral/genética
5.
Rev Med Suisse ; 19(839): 1538-1542, 2023 Aug 30.
Artículo en Francés | MEDLINE | ID: mdl-37650590

RESUMEN

Biomedical research and the pharmaceutical industry constantly explore new therapeutic strategies. A growing understanding of genetic diseases has enabled the development of «gene therapies¼. These can act either by inducing the expression of deficient genes or by silencing pathological ones. Therapies using small interfering RNA (siRNA) form a new class of treatments capable of targeting and specifically inhibiting a gene of interest. First by using lipid nanoparticles and then by engineering specific chemical modifications, progress has been made in delivering siRNA specifically into hepatocytes, representing a particular interest in the field of hepatology. The aim of this review article is to describe the mode of action of siRNA therapeutics, to review currently available treatments as well as their application, and to enumerate future treatment possibilities that are still under development.


La recherche biomédicale et l'industrie pharmaceutique s'intéressent au développement constant de nouvelles thérapies. Notre compréhension grandissante des maladies génétiques a permis le développement de nouvelles thérapies, dites « thérapies géniques ¼. Celles-ci peuvent viser à induire l'expression d'un gène lorsqu'il est déficient ou au contraire l'inhiber lorsqu'il est délétère. Les thérapies à siRNA (small interfering RNA) représentent une nouvelle classe de traitements permettant de cibler et d'inhiber spécifiquement un gène d'intérêt. Grâce à l'utilisation de nanoparticules lipidiques puis à l'aide de modifications chimiques spécifiques, des mécanismes efficaces ont été développés pour délivrer les siRNA dans les cellules du foie, représentant un intérêt particulier en hépatologie. Le but de cet article est de résumer le mode d'action des traitements à siRNA, de discuter des traitements disponibles et leur application ainsi que ceux en cours de développement.


Asunto(s)
Investigación Biomédica , Gastroenterología , Medicina , Humanos , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/uso terapéutico , Industria Farmacéutica
6.
JHEP Rep ; 5(8): 100758, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37547185

RESUMEN

Background & Aims: Body composition is sex dependent and associated with an increased mortality risk in patients with cirrhosis. We evaluated whether it was also associated with short-term mortality in patients critically ill with acute-on-chronic liver failure (ACLF). Patients and methods: We retrospectively included all patients with cirrhosis and ACLF hospitalised in the intensive care unit (ICU) of Lausanne University Hospital between 2010 and 2019 for whom an abdominal computed tomography (CT) scan performed ±7 days from admission was available. Patients from the ICU of Paul Brousse University Hospital admitted between 2017 and 2020 served as an external cohort. All body composition parameters at the third lumbar vertebral level (L3) were quantified using a deep learning-based method. Results: In total, 192 patients from Lausanne were included. Median age was 62 years and 28-day survival rate was 58.2%. In males, variables independently associated with 28-day mortality on days 1 and 3 were Chronic Liver Failure Consortium (CLIF-C) ACLF-lactate and sarcopenia. In females, CLIF-C ACLF-lactate on days 1 and 3 was the only predictor of 28-day survival. We derived two scores combining sarcopenia and the CLIF-C ACLF-lactate score on days 1 and 3, with area under the receiver operating characteristic outperforming the CLIF-C ACLF-lactate score alone in male but not in female patients. Comparable results were found in the external cohort of 58 patients and supported the sex specificity of the performance of the model. Patients with sarcopenia had increased risks of invasive fungal infection and renal replacement therapy. Conclusion: Sarcopenia was associated with 28-day mortality in male but not in female patients critically ill with ACLF. Although screening for sarcopenia could impact the management of male patients, further studies are needed in female cohorts to investigate whether other body composition parameters are associated with outcomes. Impact and implications: Body composition, easily assessed by CT, is altered in patients with cirrhosis and associated with outcome; it has never been investigated in patients critically ill with ACLF. The results of the present study, underlining the benefit of sarcopenia evaluation to improve prognosis prediction in males critically ill with ACLF, are of importance for physicians managing such patients to optimise the decision-making process toward continued treatment, liver transplantation, or limitation of care. In a wider sense, besides the number and course of organ failures, the results recall the weight of the general condition of males with ACLF at admission to ICU. In females critically ill with ACLF, in analyses limited by the sample size, none of the body composition parameters was associated with short-term mortality independently of organ failures; this suggests that the number and course of organ failures are the main determinant of mortality in these patients.

7.
Viruses ; 15(4)2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-37112849

RESUMEN

Hepatitis E virus (HEV) has received relatively little attention for decades although it is now considered as one of the most frequent causes of acute hepatitis worldwide. Our knowledge of this enterically-transmitted, positive-strand RNA virus and its life cycle remains scarce but research on HEV has gained momentum more recently. Indeed, advances in the molecular virology of hepatitis E, including the establishment of subgenomic replicons and infectious molecular clones, now allow study of the entire viral life cycle and to explore host factors required for productive infection. Here, we provide an overview on currently available systems, with an emphasis on selectable replicons and recombinant reporter genomes. Furthermore, we discuss the challenges in developing new systems which should enable to further investigate this widely distributed and important pathogen.


Asunto(s)
Virus de la Hepatitis E , Hepatitis E , Humanos , Virus de la Hepatitis E/genética , Genoma Viral , Replicón , Replicación Viral/genética , ARN Viral
8.
J Immunother Cancer ; 10(10)2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36283734

RESUMEN

BACKGROUND: Immune checkpoint inhibitors (ICIs) have become a mainstay of cancer treatment. Their immune-boosting quality has one major drawback, their proclivity to induce a broad array of immune-related adverse events (irAEs) affecting, among others, the liver and sharing some similarities with classic autoimmune liver diseases (AILD).We aimed to compare clinical, laboratory and histological features of patients with liver-related irAEs and AILD. METHODS: We systematically compared liver irAEs with AILD, namely autoimmune hepatitis (AIH) and primary biliary cholangitis, regarding their clinical, laboratory, and histological features. RESULTS: Twenty-seven patients with liver irAEs (ICI group) and 14 patients with AILD were identified. We observed three distinct ICI-induced histological liver injury patterns: hepatitic (52%), cholangitic (19%), and mixed (29%). When comparing the ICI and AILD groups, centrilobular injury as well as granuloma formation were more prevalent in the former (p=0.067 and 0.002, respectively). CD4+/CD8+ T cell ratios were heterogeneous between the two groups, without statistically significant difference but with a trend toward increased CD8+ T cells among hepatitic irAEs as compared with AIH. Pattern of liver function test alteration was predictive for the type of irAEs but did not correlate with histological severity. CONCLUSIONS: Liver irAEs have broad clinical, laboratory and histological presentations. Histological features of irAEs and AILD are distinct, likely underpinning their different immunological mechanisms.


Asunto(s)
Antineoplásicos Inmunológicos , Hepatitis Autoinmune , Enfermedades del Sistema Inmune , Hepatopatías , Neoplasias , Humanos , Antineoplásicos Inmunológicos/efectos adversos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Inmunoterapia/efectos adversos , Enfermedades del Sistema Inmune/inducido químicamente , Hepatopatías/etiología , Hepatopatías/tratamiento farmacológico , Hepatitis Autoinmune/etiología , Hepatitis Autoinmune/tratamiento farmacológico
10.
Rev Med Suisse ; 18(793): 1588-1593, 2022 Aug 31.
Artículo en Francés | MEDLINE | ID: mdl-36047549

RESUMEN

Azathioprine keeps an important place in the treatment of inflammatory bowel disease and autoimmune hepatitis. This molecule has a narrow therapeutic margin, associated with a risk of toxicity, particularly hematological and hepatic. Its complex metabolism is subject to genetic polymorphisms that are reflected in the inter-individual variability observed in the response to treatment and its tolerance profile. Hence, its use requires a good knowledge of this molecule. Treatment is initiated after a preliminary workup, followed by a progressive titration of the dosage while closely monitoring possible toxicities. Monitoring of blood levels of metabolites (including active ones) helps guide personalized dose adjustment.


L'azathioprine garde actuellement une place importante dans le traitement des maladies inflammatoires chroniques de l'intestin et de l'hépatite autoimmune. Il s'agit d'une molécule à marge thérapeutique étroite, associée à un risque de toxicité, notamment hématologique et hépatique. Son métabolisme complexe est influencé par des polymorphismes génétiques qui sont reflétés dans la variabilité interindividuelle observée dans la réponse au traitement et le profil de tolérance. Son utilisation nécessite donc une bonne connaissance de cette molécule. L'instauration du traitement se fait après un bilan préalable, puis une titration progressive des posologies, tout en surveillant étroitement les éventuelles toxicités. Le monitoring des concentrations sanguines des métabolites (notamment actifs) permet de guider l'adaptation personnalisée des posologies.


Asunto(s)
Gastroenterología , Enfermedades Inflamatorias del Intestino , Azatioprina/metabolismo , Azatioprina/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico
11.
Rev Med Suisse ; 18(793): 1606-1613, 2022 Aug 31.
Artículo en Francés | MEDLINE | ID: mdl-36047552

RESUMEN

Short telomere syndrome (STS) is a group of rare, often underrecognized, diseases caused by defects in telomere-maintenance genes, leading to abnormal telomere shortening and associated with diverse multi-organ manifestations. In pediatric patients, STS typically presents with mucocutaneous or gastrointestinal lesions, bone marrow failure and neoplasia. In adulthood, aplastic bone marrow disease, liver disease and pulmonary fibrosis are classic clinical manifestations. At present, medical treatment options for STS remain limited. Danazol, a synthetic androgenic hormone, can slow down telomere shortening and thus limit the progression of the disease. Finally, hematopoietic, hepatic and pulmonary transplantation, sometimes combined, may be discussed in a multidisciplinary setting in certain situations.


Le syndrome des télomères courts (STC) est un groupe de maladies rares dues à un défaut dans les gènes de maintenance des télomères, provoquant leur raccourcissement anormal et des manifestations cliniques multiorganiques. Dans l'enfance, le STC se présente par des lésions mucocutanées et gastro-intestinales, une insuffisance médullaire et des néoplasies. À l'âge adulte, une atteinte médullaire aplasiante, hépatique, et une fibrose pulmonaire sont des manifestations cliniques classiques. Les options thérapeutiques pour le STC restent limitées. Le danazol, une hormone androgène synthétique, permet, parfois, de freiner le raccourcissement télomérique et de limiter la progression de la maladie. Finalement, les transplantations hématopoïétique, hépatique et pulmonaire sont discutées dans certaines situations de manière multidisciplinaire.


Asunto(s)
Enfermedades de la Médula Ósea , Nefrocalcinosis , Adulto , Enfermedades de la Médula Ósea/genética , Enfermedades de la Médula Ósea/patología , Niño , Trastornos del Crecimiento , Humanos , Hipercalcemia , Enfermedades Metabólicas , Síndrome , Telómero/genética , Telómero/patología
12.
JHEP Rep ; 4(8): 100511, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35801087

RESUMEN

Background & Aims: We aimed to evaluate long-term outcome of patients with chronic non-cirrhotic extrahepatic portal vein obstruction (CNC-EHPVO) who underwent portal vein recanalisation (PVR) without transjugular intrahepatic portosystemic shunt (TIPS) insertion and to determine factors predicting PVR failure and stent occlusion. Methods: This retrospective monocentric study included all patients who underwent PVR without TIPS insertion in the context of CNC-EHPVO between the years 2000 and 2019. Primary patency was defined by the absence of a complete stent occlusion on follow-up imaging. Results: A total of 31 patients underwent PVR with a median follow-up of 52 months (24-82 months). Indications were gastrointestinal bleeding (n = 13), abdominal pain attributed to CNC-EHPVO (n = 7), prior to abdominal surgery (n = 4), and others (n = 7). Technical success was obtained in 27 patients. PVR failure was associated with extension within the intrahepatic portal veins (p = 0.005) and recanalisation for abdominal pain (p = 0.02). Adverse events occurred in 6 patients with no mortality. Anticoagulation was administered in 21 patients after technical success of PVR. In patients with technical success, 5-year primary patency was 73% and was associated with improved muscle mass (p = 0.007) and decreased spleen volume (p = 0.01) at 1 year. Furthermore, 21 (78%) patients with PVR technical success were free of portal hypertension complication at 5 years. Conclusions: PVR without TIPS insertion was feasible and safe in selected patients with CNC-EHPVO and portal hypertension with past or expected complications. Primary patency at 5 years was obtained in 3 of 4 patients with technical success of PVR and was associated with a control of complications of CNC-EHPVO. PVR was associated with improvement of sarcopenia and decreased spleen volume at 1 year. Lay summary: Patients with chronic obstruction of the portal vein and without cirrhosis or malignancy can develop complications related to the high pressure in the venous system. The present study reports long-term favourable outcome of patients in whom the obstruction was treated with stents.

13.
Swiss Med Wkly ; 152: w30138, 2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-35230042

RESUMEN

BACKGROUND AND AIMS: Non-alcoholic fatty liver disease (NAFLD) is now the first cause of chronic liver disease in developed countries. We aimed to assess trends in the prevalence of obesity, type 2 diabetes mellitus (T2DM) and NAFLD in patients undergoing liver transplantation evaluation and to assess whether obese patients were less likely to be listed or had an increased drop-out rate after listing. METHODS: We conducted a retrospective study of all consecutive patients who underwent liver transplantation evaluation at a Swiss tertiary referral centre between January 2009 and March 2020. RESULTS: A total of 242 patients were included, 83% were male. The median age was 59 years (IQR, 51-64 years). The most common causes of end-stage liver disease were viral hepatitis (28%), alcoholic liver disease (21%) and NAFLD (12%). Obesity was present in 28% of our cohort, with a significant increase over time. Prevalence of type 2 diabetes mellitus followed the same trend (p = 0.02). The proportions of non-listed and listed obese patients did not differ (21% vs. 30% respectively; p = 0.3). CONCLUSIONS: The prevalence of obesity and type 2 diabetes mellitus significantly increased over our study period. Obese patients had similar chances of being listed. The landscape of liver transplantation indications is shifting towards NAFLD, highlighting the urgent need to prevent NAFLD progression.


Asunto(s)
Diabetes Mellitus Tipo 2 , Trasplante de Hígado , Enfermedad del Hígado Graso no Alcohólico , Diabetes Mellitus Tipo 2/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Obesidad/epidemiología , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Suiza/epidemiología , Centros de Atención Terciaria
14.
Clin Microbiol Infect ; 28(4): 611.e1-611.e7, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34474121

RESUMEN

OBJECTIVES: Chronic hepatitis C virus (HCV) infection affects the immune system. Whether elimination of HCV with direct-acting antivirals (DAA) restores immunity is unclear. We used mass cytometry to get a broad and in-depth assessment of blood cell populations of patients with chronic HCV before and after DAA therapy. METHODS: Before and 12 weeks after sustained virological response (SVR12) to DAA therapy, 22 cell populations were analysed by mass cytometry in blood collected from ten healthy control individuals and 20 HCV-infected patients with (ten patients) or without (ten patients) human immunodeficiency virus (HIV) infection. RESULTS: HCV infection altered the frequency of 14/22 (64%) blood cell populations. At baseline, the frequencies (median, interquartile range (IQR); control, HCV, HCV/HIV) of intermediate monocytes (1.2, IQR 0.47-1.46; 1.76, IQR 0.83-2.66; 0.78, IQR 0.28-1.77), non-classical monocytes (1.11, IQR 0.49-1.26; 0.9, IQR 0.18-0.99; 0.54, IQR 0.28-1.77), conventional dendritic cells type 2 (0.55, IQR 0.35-0.59; 0.31, IQR 0.16-0.38; 0.19, IQR 0.11-0.36) and CD56dim natural killer cells (8.08, IQR 5.34-9.79; 4.72, IQR 2.59-6.05) 3.61, IQR 2.98-5.07) were reduced by 35% to 65%, particularly in HCV/HIV co-infected patients. In contrast, activated double-negative T cells (0.07, IQR 0.06-0.10; 0.10, IQR 0.09-0.19; 0.19, IQR 0.12-0.25), activated CD4 T cells (0.28, IQR 0.21-0.36; 0.56, IQR 0.33-0.77; 0.40, IQR 0.22-0.53) and activated CD8 T cells (0.23, IQR 0.14-0.42; 0.74, IQR 0.30-1.65; 0.80, IQR 0.58-1.16) were increased 1.4 to 3.5 times. Upon stimulation with Toll-like receptor ligands, the expression of cytokines was up-regulated in 7/9 (78%) and 17/19 (89%) of the conditions in HCV- and HCV/HIV-infected patients, respectively. Most alterations persisted at SVR12. CONCLUSIONS: Chronic HCV and HCV/HIV infections induce profound and durable perturbations of innate and adaptive immune homeostasis.


Asunto(s)
Infecciones por VIH , Hepatitis C Crónica , Hepatitis C , Antivirales/uso terapéutico , Linfocitos T CD8-positivos , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Hepacivirus , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico , Hepatitis C Crónica/tratamiento farmacológico , Humanos
15.
Hepatology ; 75(1): 170-181, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34387882

RESUMEN

BACKGROUND AND AIMS: Hepatitis E virus (HEV) is one of the most common causes of acute hepatitis worldwide. Its positive-strand RNA genome encodes three open reading frames (ORF). ORF1 is translated into a large protein composed of multiple domains and is known as the viral replicase. The RNA-dependent RNA polymerase (RDRP) domain is responsible for the synthesis of viral RNA. APPROACH AND RESULTS: Here, we identified a highly conserved α-helix located in the RDRP thumb subdomain. Nuclear magnetic resonance demonstrated an amphipathic α-helix extending from amino acids 1628 to 1644 of the ORF1 protein. Functional analyses revealed a dual role of this helix in HEV RNA replication and virus production, including assembly and release. Mutations on the hydrophobic side of the amphipathic α-helix impaired RNA replication and resulted in the selection of a second-site compensatory change in the RDRP palm subdomain. Other mutations enhanced RNA replication but impaired virus assembly and/or release. CONCLUSIONS: Structure-function analyses identified a conserved amphipathic α-helix in the thumb subdomain of the HEV RDRP with a dual role in viral RNA replication and infectious particle production. This study provides structural insights into a key segment of the ORF1 protein and describes the successful use of reverse genetics in HEV, revealing functional interactions between the RDRP thumb and palm subdomains. On a broader scale, it demonstrates that the HEV replicase, similar to those of other positive-strand RNA viruses, is also involved in virus production.


Asunto(s)
Virus de la Hepatitis E/patogenicidad , Hepatitis E/virología , ARN Polimerasa Dependiente del ARN/metabolismo , Replicación Viral/genética , Células Hep G2 , Virus de la Hepatitis E/genética , Humanos , Mutación , Conformación Proteica en Hélice alfa/genética , ARN Viral/metabolismo , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/ultraestructura , Relación Estructura-Actividad
16.
F1000Res ; 10: 400, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34900226

RESUMEN

Background: Respiratory symptoms and pneumonia are the predominant features of Coronavirus disease 2019 (COVID-19) due to emerging SARS-CoV-2 virus, but extrapulmonary manifestations are also observed. For instance, some degree of liver injury has been described among patients requiring hospital admission for severe COVID-19. However, acute febrile hepatitis as an initial or predominant manifestation of COVID-19 has been rarely reported. Case presentation: A 34-year-old man without underlying medical conditions presented with fever of unknown origin for two weeks in the absence of respiratory symptoms or other complaints. Laboratory testing revealed isolated acute hepatitis, for which an extensive microbiological work-up did not reveal identification of the causal agent. PCR testing for SARS-CoV-2 on a nasopharyngeal swab was negative on two occasions and initial serology for SARS-CoV-2 (at 15 days from symptoms onset) was also negative. However, repeated SARS-CoV-2 serological testing at 30 days demonstrated seroconversion leading to the diagnosis of COVID-19-related hepatitis. The patient's condition progressively improved, while transaminases steadily declined and eventually returned back to normal within 30 days. Conclusions: We describe here a unique case of SARS-CoV-2 isolated febrile hepatitis in a young and previously healthy man, which was diagnosed by demonstration of seroconversion, while PCR screening was negative. This case report highlights the role of repeated serological testing for the diagnosis of extrapulmonary manifestations of COVID-19.


Asunto(s)
COVID-19 , Hepatitis , Adulto , Fiebre/etiología , Hepatitis/diagnóstico , Humanos , Masculino , Reacción en Cadena de la Polimerasa , SARS-CoV-2
17.
Rev Med Suisse ; 17(748): 1457-1463, 2021 Sep 01.
Artículo en Francés | MEDLINE | ID: mdl-34468097

RESUMEN

Autoimmune hepatitis is a rare disease which can present as acute or chronic forms and can be difficult to diagnose due to its variable clinical presentation. The disease arises in genetically susceptible individuals and several triggers have been identified. The diagnosis is based on the presence of autoantibodies, elevated transaminases and serum immunoglobulin G levels as well as a compatible histology. First-line immunosuppressive treatment strategies lead to clinical remission in most patients. In case of non-response, second-line therapies can be used and in case of hepatocellular insufficiency, liver transplantation remains an excellent option.


L'hépatite autoimmune est une maladie rare, pouvant se présenter sous forme aiguë ou chronique et dont le diagnostic peut être difficile à poser en raison d'une présentation clinique variable. La maladie se développe chez des personnes génétiquement prédisposées et plusieurs événements déclencheurs ont été identifiés. Le diagnostic repose sur la présence d'autoanticorps spécifiques, d'une élévation des transaminases et des immunoglobulines G, ainsi que sur une histologie compatible. Les traitements de première ligne, immunosuppresseurs, permettent dans la plupart des cas d'obtenir une rémission clinique. En cas de non-réponse, des traitements de deuxième ligne sont disponibles et lors d'insuffisance hépatocellulaire, la transplantation hépatique reste une excellente option.


Asunto(s)
Hepatitis Autoinmune , Trasplante de Hígado , Autoanticuerpos , Hepatitis Autoinmune/diagnóstico , Hepatitis Autoinmune/tratamiento farmacológico , Hepatitis Autoinmune/epidemiología , Humanos , Inmunosupresores/uso terapéutico
18.
Swiss Med Wkly ; 151: w20502, 2021 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-34000056

RESUMEN

BACKGROUND AND AIM: Acute decompensation and death have been observed in patients with acute hepatitis E virus (HEV) infection and preexisting liver cirrhosis. However, the clinical, laboratory and histological features need to be fully characterised. METHODS: Some of us recently described the histological presentation of hepatitis E in a large panel of liver tissue specimens. Here, we conducted a case-control study to investigate the clinical and laboratory features of the subset of patients with HEV-related acute-on-chronic liver failure (ACLF) and death. Each patient was matched to three control patients with histologically confirmed severe alcoholic hepatitis based on sex, age, total bilirubin, INR, serum creatinine and MELD score on admission. RESULTS: Of 5 patients who died in a context of HEV-related ACLF, 3 (60%) were male and the median age was 66 years (range 51–76). Median alanine aminotransferase (ALT) at presentation was 2610 U/l (range 705–3134) and aspartate aminotransferase (AST) 2818 U/l (range 1176–8611). Liver function was heavily altered in all patients. Histological analyses revealed steatohepatitis on a background of cirrhosis, suggestive of an alcoholic or nonalcoholic origin. Based on histopathology, alcoholic hepatitis was initially suspected in two patients and corticosteroid treatment was initiated. Ribavirin was started in four patients. Median time from hospitalisation to death was 17 days (range 6–25 days). AST levels in patients with HEV-related ACLF were significantly higher as compared to the matched patients with severe alcoholic hepatitis. CONCLUSION: Typical histopathological features of viral hepatitis may be absent in ACLF caused by HEV infection. HEV infection should be sought in acute decompensation of cirrhosis and ACLF even in the absence of histological changes suggesting viral infection.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Virus de la Hepatitis E , Hepatitis E , Anciano , Estudios de Casos y Controles , Hepatitis E/complicaciones , Virus de la Hepatitis E/genética , Humanos , Masculino , Persona de Mediana Edad , Transaminasas
19.
PLoS One ; 16(4): e0250347, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33905426

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) is a major global health challenge with approximately 250-350 million chronically infected individuals. An improved understanding of the demographic features and outcomes of chronic HBV infection and hepatitis D virus (HDV) infection in low-endemic areas may improve prevention, early identification and management both at individual and community levels. Here, we retrospectively analyzed the demographic and clinical characteristics, treatment rates and outcomes of adult patients with chronic HBV infection with or without HDV coinfection examined at Lausanne University Hospital, Switzerland over a 10-year period. METHODS: We analyzed the medical records of all adult patients with chronic HBV and HDV infection examined in our center between 2007 and 2016. Liver-related outcome was defined as the occurrence of cirrhosis, hepatocellular carcinoma, liver transplantation or liver-related death. Analyses were performed using logistic regression and results were reported as odds ratio (OR) and 95% confidence interval (CI). RESULTS: Of 672 consecutive patients, 421 (62.6%) were male, median age was 36 years (interquartile range, 28-46 years), and 233 (34.7%) were of African origin. The prevalence of HDV coinfection was 7.1% and the proportion of anti-HDV-positive patients with detectable HDV RNA was 70.0%. In multivariate analysis, HDV coinfection was the strongest predictor for liver-related outcome (OR 6.06, 95% CI 2.93-12.54, p<0.001), followed by HBeAg positivity (OR 2.47, 95% CI 1.30-4.69, p = 0.006), age (OR per 10-year increase 2.03, 95% CI 1.63-2.52, p<0.001) and sex (OR for female 0.39, 95% CI 0.22-0.71, p = 0.002). The predictive accuracy of the multivariate model was high (receiver operator characteristic area under the curve 0.81). CONCLUSION: This retrospective study underscores the importance of migration in the epidemiology of chronic hepatitis B in low-endemic areas. HDV coinfection, HBeAg positivity and age predicted liver-related outcomes while female sex had a protective effect.


Asunto(s)
Carcinoma Hepatocelular/epidemiología , Hepatitis B Crónica/epidemiología , Hepatitis D/epidemiología , Cirrosis Hepática/epidemiología , Neoplasias Hepáticas/epidemiología , Adulto , Población Negra , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/virología , Coinfección , Femenino , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/patogenicidad , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/mortalidad , Hepatitis B Crónica/virología , Hepatitis D/complicaciones , Hepatitis D/mortalidad , Hepatitis D/virología , Virus de la Hepatitis Delta/patogenicidad , Migración Humana/estadística & datos numéricos , Humanos , Cirrosis Hepática/etiología , Cirrosis Hepática/mortalidad , Cirrosis Hepática/virología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/virología , Trasplante de Hígado/estadística & datos numéricos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , ARN Viral/sangre , Estudios Retrospectivos , Factores Sexuales , Análisis de Supervivencia , Suiza/epidemiología , Población Blanca
20.
Rev Med Suisse ; 17(720-1): 29-32, 2021 Jan 13.
Artículo en Francés | MEDLINE | ID: mdl-33443827

RESUMEN

The year 2020 has been dominated by the coronavirus disease 2019 (COVID-19) pandemic, with important lessons learned also in gastroenterology and hepatology. Major advances, however, have also been made in other areas, a selection of which is highlighted in this article.


L'année 2020 a été marquée par la pandémie de Covid-19. Un certain nombre d'enseignements de cette pandémie ont pu être tirés également en gastroentérologie et en hépatologie. D'autre part, des progrès importants ont aussi été réalisés en dehors du Covid-19, dont une sélection est présentée dans cet article.


Asunto(s)
Gastroenterología/tendencias , COVID-19 , Humanos , Pandemias
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