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1.
Am J Gastroenterol ; 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32224704

RESUMO

Management of hepatic encephalopathy (HE) remains challenging from a medical and psychosocial perspective. Members of the International Society for Hepatic Encephalopathy and Nitrogen Metabolism recognized 5 key unresolved questions in HE management focused on (i) driving, (ii) ammonia levels in clinical practice, (iii) testing strategies for covert or minimal HE, (iv) therapeutic options, and (v) nutrition and patient-reported outcomes. The consensus document addresses these topical issues with a succinct review of the literature and statements that critically evaluate the current science and practice, laying the groundwork for future investigations.

2.
Nature ; 575(7783): 505-511, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31723265

RESUMO

Chronic liver disease due to alcohol-use disorder contributes markedly to the global burden of disease and mortality1-3. Alcoholic hepatitis is a severe and life-threatening form of alcohol-associated liver disease. The gut microbiota promotes ethanol-induced liver disease in mice4, but little is known about the microbial factors that are responsible for this process. Here we identify cytolysin-a two-subunit exotoxin that is secreted by Enterococcus faecalis5,6-as a cause of hepatocyte death and liver injury. Compared with non-alcoholic individuals or patients with alcohol-use disorder, patients with alcoholic hepatitis have increased faecal numbers of E. faecalis. The presence of cytolysin-positive (cytolytic) E. faecalis correlated with the severity of liver disease and with mortality in patients with alcoholic hepatitis. Using humanized mice that were colonized with bacteria from the faeces of patients with alcoholic hepatitis, we investigated the therapeutic effects of bacteriophages that target cytolytic E. faecalis. We found that these bacteriophages decrease cytolysin in the liver and abolish ethanol-induced liver disease in humanized mice. Our findings link cytolytic E. faecalis with more severe clinical outcomes and increased mortality in patients with alcoholic hepatitis. We show that bacteriophages can specifically target cytolytic E. faecalis, which provides a method for precisely editing the intestinal microbiota. A clinical trial with a larger cohort is required to validate the relevance of our findings in humans, and to test whether this therapeutic approach is effective for patients with alcoholic hepatitis.

3.
Aliment Pharmacol Ther ; 50(4): 435-441, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31169941

RESUMO

BACKGROUND: Rifaximin reduces the risk of overt hepatic encephalopathy (HE) and is associated with significant reductions in hospitalisations and 30-day readmissions. AIM: To examine the outcomes of patients listed for liver transplantation with a diagnosis of HE on rifaximin compared to those naïve to the drug. METHODS: Patient records of those listed for liver transplantation over a 2-year period were retrospectively reviewed. Patients were included if they had at least two episodes of overt HE resulting in hospitalisation or were encephalopathic at the time of assessment. RESULTS: Of the 622 patients listed for transplantation, 101 had HE. Sixty-six patients were treated with rifaximin and 35 were naïve at listing. The use of concurrent lactulose was not significantly different between groups. Median MELD score was similar (15 [14-16)] rifaximin-treated and 16 [14-18] rifaximin-naïve). Patients on the waiting list treated with rifaximin had reduced all-cause admissions, episodes of spontaneous bacterial peritonitis and variceal bleeding. Mean length of stay was 9 days (95% CI 6-12) in the rifaximin-treated group vs 14 (95% CI 7-21) in the rifaximin-naïve group. Multivariate regression analysis demonstrated that rifaximin was independently associated with an increase in average days to readmission (adjusted effect estimate 71, 95% CI 3-140 days) and reduced likelihood of requirement for prioritisation on the waiting list (odds ratio 0.29; 95% CI 0.89-0.93). CONCLUSION: Rifaximin prescribed for HE in patients listed for liver transplantation improved outcomes with significant reduction in admissions related to spontaneous bacterial peritonitis, ascites and variceal bleeding.

4.
Dig Dis Sci ; 64(7): 1878-1892, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31076986

RESUMO

BACKGROUND: Alcohol-related liver disease is one of the most prevalent chronic liver diseases worldwide. Mechanisms involved in the pathogenesis of alcohol-related liver disease are not well understood. Oxylipins play a crucial role in numerous biological processes and pathological conditions. Nevertheless, oxylipins are not well studied in alcohol-related liver disease. AIMS: (1) To characterize the patterns of bioactive ω-3 and ω-6 polyunsaturated fatty acid metabolites in alcohol use disorder and alcoholic hepatitis patients and (2) to identify associations of serum oxylipins with clinical parameters in patients with alcohol-related liver disease. METHODS: We performed a comprehensive liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis of serum and fecal oxylipins derived from ω-6 arachidonic acid, ω-3 eicosapentaenoic acid, and docosahexaenoic acid in a patient cohort with alcohol-related liver disease. RESULTS: Our results show profound alterations in the serum oxylipin profile of patients with alcohol use disorder and alcoholic hepatitis compared to nonalcoholic controls. Spearman correlation of the oxylipins with clinical parameters shows a link between different serum oxylipins and intestinal permeability, aspartate aminotransferase, bilirubin, albumin, international normalized ratio, platelet count, steatosis, fibrosis and model for end-stage liver disease score. Especially, higher level of serum 20-HETE was significantly associated with decreased albumin, increased hepatic steatosis, polymorphonuclear infiltration, and 90-day mortality. CONCLUSIONS: Patients with alcohol-related liver disease have different oxylipin profiles. Future studies are required to confirm oxylipins as disease biomarker or to connect oxylipins to disease pathogenesis.


Assuntos
Alcoolismo/sangue , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6/sangue , Fezes/química , Hepatite Alcoólica/sangue , Oxilipinas/sangue , Adulto , Idoso , Alcoolismo/diagnóstico , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Feminino , Hepatite Alcoólica/diagnóstico , Humanos , Masculino , Metabolômica/métodos , Pessoa de Meia-Idade , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
6.
Liver Int ; 38(11): 1988-1996, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29768734

RESUMO

BACKGROUND & AIMS: A simultaneous decline in pro- and anticoagulant drivers in patients with liver diseases results in a "rebalanced" haemostatic system, even in acutely ill patients. Nevertheless, both bleeding and thrombotic events are common. Here, we explored efficacy of pro- and antihaemostatic strategies in compensated and acutely ill cirrhotics which may be unpredictable given the profound haemostatic changes. METHODS: We tested the effects in vitro of the addition of clinically relevant doses of commonly used pro- and antihaemostatic strategies in plasma from healthy individuals (n = 30) and patients with compensated (n = 18) and acutely decompensated cirrhosis (n = 18), and acute-on-chronic liver failure (n = 10). We used thrombin generation tests and fibrin clot permeability assays to assess potency of various approaches. RESULTS: Fresh frozen plasma and recombinant factor VIIa modestly increased thrombin generation (10%-20%). Prothrombin complex concentrate increased thrombin generation two-fold in controls and 2-4-fold in patients. Clot permeability decreased after addition of fibrinogen concentrate by 51% in controls and by 50%-60% in patients. Low molecular weight heparin decreased thrombin generation by 18% in controls and by 23%-54% in patients. Similarly, dabigatran decreased thrombin generation by 33% in controls and by 47%-100% in patients. In contrast, rivaroxaban decreased thrombin generation by 55% in controls, but only by 11%-38% in patients. CONCLUSIONS: These in vitro data suggest little prohaemostatic effect of fresh frozen plasma and recombinant factor VIIa in acutely ill cirrhotics, whereas prothrombin complex concentrate and fibrinogen concentrate clearly improved haemostasis. Furthermore, our data suggest the requirement for dose adjustments of commonly used anticoagulants in these patients.


Assuntos
Anticoagulantes/uso terapêutico , Fator VIIa/uso terapêutico , Cirrose Hepática/terapia , Plasma , Trombina/metabolismo , Adulto , Idoso , Benzimidazóis/uso terapêutico , Fatores de Coagulação Sanguínea/uso terapêutico , Testes de Coagulação Sanguínea , Dabigatrana , Feminino , Hemorragia/terapia , Hemostasia/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Rivaroxabana
7.
Br J Nurs ; 27(Sup3): S7-S13, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29411990

RESUMO

Overt and covert hepatic encephalopathy (HE) are debilitating complications of cirrhosis. HE results in a poor quality of life for patients and their caregivers and, unless there is access to liver transplantation, the prognosis is poor. The development of overt HE is often unpredictable, and its management, particularly in the ward, remains challenging. There is an urgent need for novel approaches to treat HE. Until recently, therapies for this complication were disappointing, with frequently intolerable side effects such as diarrhoea and faecal incontinence. However, a non-absorbable antibiotic, rifaximin, * has been approved for the prevention of recurrent overt HE. It aims to reduce hospitalisation and resource use, as well as improve patients' quality of life. This article describes the practical aspects of diagnosing, classifying and managing HE. It reviews the pharmacological options for the treatment and prophylaxis of overt HE, and explores the evidence base demonstrating that rifaximin reduces the recurrence of overt HE.


Assuntos
Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/terapia , Algoritmos , Encefalopatia Hepática/classificação , Humanos
8.
J Crit Care ; 43: 54-60, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28843665

RESUMO

BACKGROUND: Cirrhotic patients have complex haemostatic abnormalities. Current evidence suggests stable cirrhotic (SC) patients have a "re-balanced" haemostatic state. However, limited data exists in acute decompensated (AD) or acute on chronic liver failure (ACLF) patients. METHODS: We utilised thrombin generation analysis, fibrinolysis assessment, and evaluation of haemostatic parameters to assess haemostasis in liver disease of progressive severity. RESULTS: The study cohorts were comprised of: SC, n=8; AD n=44; ACLF, n=17; and Healthy Control (HC), n=35. There was a progressive increase across the cohorts in INR (p=0.0001), Factor VIII (p=0.0001) and VWF levels (p=0.0001) and a correspondingly decrease in anti-thrombin (p=0.0001), ADAMTS-13 (p=0.01) and fibrinogen levels (p=0.0001). In the presence of thrombomodulin, thrombin generation was equivalent or significantly higher in all the cohorts compared to HC (p=0.0001). Compared to AD, ACLF had a lower ETP (p=0.002) and thrombin peak (p=0.0001). There was no significant difference across the cohorts in clot lysis time (p=0.07), although compared to HC, AD had a significantly shorter lysis time (p=0.001). CONCLUSIONS: Our cohorts, despite significant differences in haemostatic parameters, displayed intact thrombin generation but progressive hypo-functional clot stability and potentially but not universal hyper-functional haemostasis.


Assuntos
Insuficiência Hepática Crônica Agudizada/fisiopatologia , Estado Terminal , Hemostasia , Insuficiência Hepática Crônica Agudizada/tratamento farmacológico , Insuficiência Hepática Crônica Agudizada/metabolismo , Adulto , Idoso , Coagulação Sanguínea , Testes de Coagulação Sanguínea , Estado Terminal/terapia , Progressão da Doença , Fator VIII/metabolismo , Feminino , Fibrinólise , Hemostáticos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Trombina/metabolismo , Trombomodulina/metabolismo
9.
Frontline Gastroenterol ; 8(4): 243-251, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29067149

RESUMO

OBJECTIVE: To compare all-cause and liver-related hospital resource use in the 6 and 12 months pre-rifaximin-α and post-rifaximin-α initiation in UK patients with hepatic encephalopathy (HE). DESIGN: A UK multicentre, retrospective, observational study. Patients' medical records were reviewed for demographics, clinical outcomes and adverse events (AEs) to rifaximin-α. Details of hospital admissions/attendances in the 6 and 12 months pre-rifaximin-α and post-rifaximin-α initiation were extracted from hospital electronic databases. SETTING: 13 National Health Service centres. PATIENTS: 207 patients with HE who initiated rifaximin-α between July 2008 and May 2014. Hospital resource use data were available for 145/207 patients. MAIN OUTCOME MEASURE: Change in mean number of liver-related hospital bed days/patient (total and critical care) between the 6 months pre-rifaximin-α and post-rifaximin-α initiation. RESULTS: Comparing the 6 months pre-rifaximin-α and post-rifaximin-α initiation in alive patients at the end of the observation period (N=114): there were significant reductions in the mean number of hospitalisations/patient (liver-related 1.3 to 0.5, p<0.001; all-cause 1.9 to 0.9, p<0.001), hospital bed days/patient (liver-related 17.8 to 6.8, p<0.001; all-cause 25.4 to 10.6, p<0.001), 30-day hospital readmissions/patient (liver-related 0.5 to 0.2, p=0.039; all-cause 0.8 to 0.4, p=0.024) and emergency department (ED) attendances/patient (all-cause, 1.0 to 0.5, p<0.001). The mean critical care bed days/patient reduced significantly for all-cause admissions (1.3 to 0.3, p=0.049); non-significant reduction for liver-related admissions. 4% of patients (9/207) developed AEs. CONCLUSIONS: In UK clinical practice, treatment with rifaximin-α for HE is well-tolerated and associated with significant reductions in hospitalisations, bed days (including critical care), ED attendances and 30-day readmissions.

10.
Am J Physiol Gastrointest Liver Physiol ; 313(3): G203-G211, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28642299

RESUMO

Patients with alcohol-related cirrhosis (ALD) are prone to infection. Circulating neutrophils in ALD are dysfunctional and predict development of sepsis, organ dysfunction, and survival. Neutrophil granules are important effector organelles containing a toxic array of microbicidal proteins, whose controlled release is required to kill microorganisms while minimizing inflammation and damage to host tissue. We investigated the role of these granular responses in contributing to immune disarray in ALD. Neutrophil granular content and mobilization were measured by flow cytometric quantitation of cell-surface/intracellular markers, [secretory vesicles (CD11b), secondary granules (CD66b), and primary granules (CD63; myeloperoxidase)] before and after bacterial stimulation in 29 patients with ALD cirrhosis (15 abstinent; 14 actively drinking) compared with healthy controls (HC). ImageStream Flow Cytometry characterized localization of granule subsets within the intracellular and cell-surface compartments. The plasma cytokine environment was analyzed using ELISA/cytokine bead array. Circulating neutrophils were primed in the resting state with upregulated surface expression of CD11b (P = 0.0001) in a cytokine milieu rich in IL-8 (P < 0.001) and lactoferrin (P = 0.035). Neutrophils showed exaggerated mobilization to the cell surface of primary granules at baseline (P = 0.001) and in response to N-formyl-l-methionyl-l-leucyl-l-phenylalanine (P = 0.009) and Escherichia coli (P = 0.0003) in ALD. There was no deficit in granule content or mobilization to the cell membrane in any granule subset observed. Paradoxically, active alcohol consumption abrogated the hyperresponsive neutrophil granular responses compared with their abstinent counterparts. Neutrophils are preprimed at baseline with augmented effector organelle mobilization in response to bacterial stimulation; neutrophil degranulation is not a mechanism leading to innate immunoparesis in ALD.NEW & NOTEWORTHY Neutrophil granule release is dysregulated in patients with alcohol-related cirrhosis (ALD) with augmented effector organelle mobilization and microbiocidal protein release. Neutrophil granules are upregulated in ALD at baseline and demonstrate augmented responses to bacterial challenge. The granular responses in ALD did not contribute to the observed functional deficit in innate immunity but rather were dysregulated and hyperresponsive, which may induce bystander damage to host tissue. Paradoxically, active alcohol consumption abrogated the excessive neutrophil granular responses to bacterial stimulus compared with their abstinent counterparts.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Cirrose Hepática Alcoólica/patologia , Neutrófilos/fisiologia , Adulto , Estudos de Casos e Controles , Feminino , Regulação da Expressão Gênica , Humanos , Cirrose Hepática Alcoólica/metabolismo , Masculino , Pessoa de Meia-Idade , Vesículas Secretórias/fisiologia
11.
Gut ; 66(3): 519-529, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-26860769

RESUMO

OBJECTIVE: In order to explain the increased susceptibility to serious infection in alcoholic hepatitis, we evaluated monocyte phagocytosis, aberrations of associated signalling pathways and their reversibility, and whether phagocytic defects could predict subsequent infection. DESIGN: Monocytes were identified from blood samples of 42 patients with severe alcoholic hepatitis using monoclonal antibody to CD14. Phagocytosis and monocyte oxidative burst (MOB) were measured ex vivo using flow cytometry, luminometry and bacterial killing assays. Defects were related to the subsequent development of infection. Intracellular signalling pathways were investigated using western blotting and PCR. Interferon-γ (IFN-γ) was evaluated for its therapeutic potential in reversing phagocytic defects. Paired longitudinal samples were used to evaluate the effect of in vivo prednisolone therapy. RESULTS: MOB, production of superoxide and bacterial killing in response to Escherichia coli were markedly impaired in patients with alcoholic hepatitis. Pretreatment MOB predicted development of infection within two weeks with sensitivity and specificity that were superior to available clinical markers. Accordingly, defective MOB was associated with death at 28 and 90 days. Expression of the gp91 phox subunit of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase was reduced in patients with alcoholic hepatitis demonstrating defective MOB. Monocytes were refractory to IFN-γ stimulation and showed high levels of a negative regulator of cytokine signalling, suppressor of cytokine signalling-1. MOB was unaffected by 7 days in vivo prednisolone therapy. CONCLUSIONS: Monocyte oxidative burst and bacterial killing is impaired in alcoholic hepatitis while bacterial uptake by phagocytosis is preserved. Defective MOB is associated with reduced expression of NADPH oxidase in these patients and predicts the development of infection and death.


Assuntos
Infecções Bacterianas/imunologia , Hepatite Alcoólica/fisiopatologia , Monócitos/fisiologia , NADPH Oxidases/metabolismo , Fagocitose , Explosão Respiratória , Adulto , Anti-Inflamatórios/uso terapêutico , Estudos de Casos e Controles , Células Cultivadas , Técnicas de Cocultura , Contagem de Colônia Microbiana , Escherichia coli/imunologia , Feminino , Hepatite Alcoólica/tratamento farmacológico , Hepatite Alcoólica/enzimologia , Humanos , Interferon gama/farmacologia , Masculino , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , NADPH Oxidase 2 , Valor Preditivo dos Testes , Prednisolona/uso terapêutico , Explosão Respiratória/efeitos dos fármacos , Transdução de Sinais , Proteína 1 Supressora da Sinalização de Citocina/metabolismo
13.
J Hepatol ; 64(5): 1058-1067, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26795831

RESUMO

BACKGROUND & AIMS: Predicting survival in decompensated cirrhosis (DC) is important in decision making for liver transplantation and resource allocation. We investigated whether high-resolution metabolic profiling can determine a metabolic phenotype associated with 90-day survival. METHODS: Two hundred and forty-eight subjects underwent plasma metabotyping by (1)H nuclear magnetic resonance (NMR) spectroscopy and reversed-phase ultra-performance liquid chromatography coupled to time-of-flight mass spectrometry (UPLC-TOF-MS; DC: 80-derivation set, 101-validation; stable cirrhosis (CLD) 20 and 47 healthy controls (HC)). RESULTS: (1)H NMR metabotyping accurately discriminated between surviving and non-surviving patients with DC. The NMR plasma profiles of non-survivors were attributed to reduced phosphatidylcholines and lipid resonances, with increased lactate, tyrosine, methionine and phenylalanine signal intensities. This was confirmed on external validation (area under the receiver operating curve [AUROC]=0.96 (95% CI 0.90-1.00, sensitivity 98%, specificity 89%). UPLC-TOF-MS confirmed that lysophosphatidylcholines and phosphatidylcholines [LPC/PC] were downregulated in non-survivors (UPLC-TOF-MS profiles AUROC of 0.94 (95% CI 0.89-0.98, sensitivity 100%, specificity 85% [positive ion detection])). LPC concentrations negatively correlated with circulating markers of cell death (M30 and M65) levels in DC. Histological examination of liver tissue from DC patients confirmed increased hepatocyte cell death compared to controls. Cross liver sampling at time of liver transplantation demonstrated that hepatic endothelial beds are a source of increased circulating total cytokeratin-18 in DC. CONCLUSION: Plasma metabotyping accurately predicts mortality in DC. LPC and amino acid dysregulation is associated with increased mortality and severity of disease reflecting hepatocyte cell death.


Assuntos
Citocinas/sangue , Cirrose Hepática/sangue , Fígado/patologia , Metabolômica/métodos , Adulto , Idoso , Biomarcadores/sangue , Biópsia , Morte Celular , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Fígado/metabolismo , Cirrose Hepática/mortalidade , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo , Reino Unido/epidemiologia , Adulto Jovem
15.
Crit Care Med ; 44(1): 43-53, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26457748

RESUMO

OBJECTIVES: There is a marked propensity for patients with acetaminophen-induced acute liver failure to develop sepsis, which may culminate in multiple organ failure and death. Toll-like receptors sense pathogens and induce inflammatory responses, but whether this is protective or detrimental in acetaminophen-induced acute liver failure remains unknown. DESIGN, SETTING, AND PATIENTS: We assessed Toll-like receptor expression on circulating neutrophils and their function in 24 patients with acetaminophen-induced acute liver failure and compared with 10 healthy controls. INTERVENTIONS: Neutrophil Toll-like receptor 2, -4, and -9 expression and cytokine production and function were studied ex vivo at baseline and following stimulation with lipopolysaccharide, oligodeoxynucleotides, ammonium chloride, and interleukin-8. To examine the influence of acetaminophen-induced acute liver failure plasma and endogenous DNA on Toll-like receptors-9 expression, healthy neutrophils were incubated with acetaminophen-induced acute liver failure plasma with and without deoxyribonuclease-I. MEASUREMENTS AND MAIN RESULTS: Circulating neutrophil Toll-like receptor 9 expression was increased in acetaminophen-induced acute liver failure on day 1 compared with healthy controls (p = 0.0002), whereas Toll-like receptor 4 expression was decreased compared with healthy controls (p < 0.0001). Toll-like receptor 2 expression was unchanged. Neutrophil phagocytic activity was decreased, and spontaneous oxidative burst increased in all patients with acetaminophen-induced acute liver failure compared with healthy controls (p < 0.0001). Neutrophil Toll-like receptor 9 expression correlated with plasma interleukin-8 and peak ammonia concentration (r = 0.6; p < 0.05) and increased with severity of hepatic encephalopathy (grade 0-2 vs 3/4) and systemic inflammatory response syndrome score (0-1 vs 2-4) (p < 0.05). Those patients with advanced hepatic encephalopathy (grade 3/4) or high systemic inflammatory response syndrome score (2-4) on day 1 had higher neutrophil Toll-like receptor 9 expression, arterial ammonia concentration, and plasma interleukin-8 associated with neutrophil exhaustion. Healthy neutrophil Toll-like receptor 9 expression increased upon stimulation with acetaminophen-induced acute liver failure plasma, which was abrogated by preincubation with deoxyribonuclease-I. Intracellular Toll-like receptor 9 was induced by costimulation with interleukin-8 and ammonia. CONCLUSION: These data point to neutrophil Toll-like receptor 9 expression in acetaminophen-induced acute liver failure being mediated both by circulating endogenous DNA as well as ammonia and interleukin-8 in a synergistic manner inducing systemic inflammation, neutrophil exhaustion, and exacerbating hepatic encephalopathy.


Assuntos
Acetaminofen/efeitos adversos , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/imunologia , Neutrófilos/imunologia , Síndrome de Resposta Inflamatória Sistêmica/induzido quimicamente , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Receptor Toll-Like 9/biossíntese , Adulto , Estudos de Coortes , Feminino , Humanos , Falência Hepática Aguda/sangue , Masculino , Pessoa de Meia-Idade , Síndrome de Resposta Inflamatória Sistêmica/sangue , Adulto Jovem
16.
Metab Brain Dis ; 31(6): 1327-1337, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26446022

RESUMO

A clinical science workshop was held at the ISHEN meeting in London on Friday 11th September 2014 with the aim of thrashing out how we might translate what we know about the central role of the gut-liver-brain axis into targets which we can use in the treatment of hepatic encephalopathy (HE). This review summarises the integral role that inter-organ ammonia metabolism plays in the pathogenesis of HE with specific discussion of the roles that the small and large intestine, liver, brain, kidney and muscle assume in ammonia and glutamine metabolism. Most recently, the salivary and gut microbiome have been shown to underpin the pathophysiological changes which culminate in HE and patients with advanced cirrhosis present with enteric dysbiosis with small bowel bacterial overgrowth and translocation of bacteria and their products across a leaky gut epithelial barrier. Resident macrophages within the liver are able to sense bacterial degradation products initiating a pro-inflammatory response within the hepatic parenchyma and release of cytokines such as tumour necrosis factor alpha (TNF-α) and interleukin-8 into the systemic circulation. The endotoxemia and systemic inflammatory response that are generated predispose both to the development of infection as well as the manifestation of covert and overt HE. Co-morbidities such as diabetes and insulin resistance, which commonly accompany cirrhosis, may promote slow gut transit, promote bacterial overgrowth and increase glutaminase activity and may need to be acknowledged in HE risk stratification assessments and therapeutic regimens. Therapies are discussed which target ammonia production, utilisation or excretion at an individual organ level, or which reduce systemic inflammation and endotoxemia which are known to exacerbate the cerebral effects of ammonia in HE. The ideal therapeutic strategy would be to use an agent that can reduce hyperammonemia and reduce systemic inflammation or perhaps to adopt a combination of therapies that can address both.


Assuntos
Encéfalo/metabolismo , Sistemas de Liberação de Medicamentos/tendências , Educação/tendências , Trato Gastrointestinal/metabolismo , Encefalopatia Hepática/metabolismo , Fígado/metabolismo , Amônia/antagonistas & inibidores , Amônia/metabolismo , Animais , Anti-Inflamatórios/administração & dosagem , Encéfalo/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Encefalopatia Hepática/tratamento farmacológico , Humanos , Hiperamonemia/tratamento farmacológico , Hiperamonemia/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Fígado/efeitos dos fármacos
17.
Eur J Gastroenterol Hepatol ; 28(2): 146-52, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26600154

RESUMO

INTRODUCTION: Hepatic encephalopathy is defined as brain dysfunction caused by liver insufficiency and/or portosystemic shunting. Symptoms include nonspecific cognitive impairment, personality changes and changes in consciousness. Overt (symptomatic) hepatic encephalopathy is a common complication of cirrhosis that is associated with a poor prognosis. Patients with hepatic encephalopathy may present to healthcare providers who do not have primary responsibility for management of patients with cirrhosis. Therefore, we developed a series of 'consensus points' to provide some guidance on management. METHODS: Using a modified 'Delphi' process, consensus statements were developed that summarize our recommendations for the diagnosis and management of patients with hepatic encephalopathy. Points on which full consensus could not be reached are also discussed. RESULTS: Our recommendations emphasize the role of all healthcare providers in the identification of cognitive impairment in patients with cirrhosis and provide guidance on steps that might be considered to make a diagnosis of overt hepatic encephalopathy. In addition, treatment recommendations are summarized. Minimal hepatic encephalopathy can have a significant impact on patients; however, in most circumstances identification and management of minimal hepatic encephalopathy remains the responsibility of specialists in liver diseases. CONCLUSION: Our opinion statements aim to define the roles and responsibilities of all healthcare providers who at times care for patients with cirrhosis and hepatic encephalopathy. We suggest that these recommendations be considered further by colleagues in other disciplines and hope that future guidelines consider the management of patients with cirrhosis and with a 'suspicion' of cognitive impairment through to a formal diagnosis of hepatic encephalopathy.


Assuntos
Gastroenterologia , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/terapia , Especialização , Comitês Consultivos , Algoritmos , Cognição , Consenso , Procedimentos Clínicos , Técnica Delfos , Necessidades e Demandas de Serviços de Saúde , Encefalopatia Hepática/psicologia , Humanos , Determinação de Necessidades de Cuidados de Saúde , Papel do Médico , Valor Preditivo dos Testes , Resultado do Tratamento
18.
Lancet ; 385 Suppl 1: S22, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26312844

RESUMO

BACKGROUND: Alcoholic hepatitis is characterised by florid hepatic inflammation, liver failure, and death within 28 days in 35% of patients. We recently showed proliferative peripheral blood mononuclear cell (PBMC) responses to alcohol dehydrogenase (ADH) in patients with alcohol-related cirrhosis, associated with T-helper-type 1 (Th1) immunity and disease severity. We aimed to define whether ADH-specific cellular immunity is present in alcoholic hepatitis. METHODS: PBMCs were collected from 15 patients with alcoholic hepatitis (modified Maddrey's discriminant function >32), nine with alcohol-related cirrhosis (long-term alcohol abstinence), and three healthy controls. 25 overlapping peptides, spanning the human ADH ß1 subunit, were constructed. Proliferation to ADH peptides (1 × 10(5) cells per well, cultured with 10 mM peptides for 7 days) was assessed by (3)H-thymidine incorporation. A stimulation index (SI) of 2·5 or more was regarded as positive. ELISA measured concentrations of interferon γ (IFNγ), interleukin (IL) 17, and IL4 from supernatant. FINDINGS: PBMCs from seven of 15 patients with alcoholic hepatitis recognised one to three ADH peptides (SI ≤5·7). IFNγ (mean 390·9 pg/mL [SE 31·4]) was detected in 48% of wells, IL17 (20·1 [3 ·4]) in 15%, and IL4 (90·5 [9·3]) in 14%. PBMCs from six of the nine patients with alcohol-related cirrhosis recognised one to five peptides (SI ≤5·2). IFNγ (360·7 [58·9], p>0·05) was detected in 31% of wells, IL17 (57·7 [10·9], p=0·0006) in 19%, and IL4 (219·7 [11·2], p=0·0012) in 28%. PBMCs from two healthy controls recognised one to two peptides (SI ≤3·1); all cytokine levels were below baseline. INTERPRETATION: Proliferative anti-ADH immune responses in alcoholic hepatitis focused on individual epitopic regions. Predominance of proinflammatory Th1 responses was more pronounced in alcoholic hepatitis than in alcoholic-related cirrhosis. This finding requires investigation of targeted therapies to inhibit Th1 immunity in alcoholic hepatitis. FUNDING: Wellcome Trust.

19.
J Clin Exp Hepatol ; 5(Suppl 1): S7-S20, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26041962

RESUMO

The syndrome we refer to as Hepatic Encephalopathy (HE) was first characterized by a team of Nobel Prize winning physiologists led by Pavlov and Nencki at the Imperial Institute of Experimental Medicine in Russia in the 1890's. This focused upon the key observation that performing a portocaval shunt, which bypassed nitrogen-rich blood away from the liver, induced elevated blood and brain ammonia concentrations in association with profound neurobehavioral changes. There exists however a spectrum of metabolic encephalopathies attributable to a variety (or even absence) of liver hepatocellular dysfunctions and it is this spectrum rather than a single disease entity that has come to be defined as HE. Differences in the underlying pathophysiology, treatment responses and outcomes can therefore be highly variable between acute and chronic HE. The term also fails to articulate quite how systemic the syndrome of HE can be and how it can be influenced by the gastrointestinal, renal, nervous, or immune systems without any change in background liver function. The pathogenesis of HE therefore encapsulates a complex network of interdependent organ systems which as yet remain poorly characterized. There is nonetheless a growing recognition that there is a complex but influential synergistic relationship between ammonia, inflammation (sterile and non-sterile) and oxidative stress in the pathogenesis HE which develops in an environment of functional immunoparesis in patients with liver dysfunction. Therapeutic strategies are thus moving further away from the traditional specialty of hepatology and more towards novel immune and inflammatory targets which will be discussed in this review.

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