Hepatic Encephalopathy

A Brief History of Hepatic Encephalopathy

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Preloading Coil in Plug Method (p-CIP) with the AVP 2 for large Portosystemic Shunt Embolization

Hepatic encephalopathy caused by a large portosystemic shunt (PSS) can be treated by endovascular embolization of the shunt. The PSS diameter can be >20 mm; it occasionally poses technical difficulties. Here, a 72-year-old woman with liver cirrhosis, hyperammonemia, and large spleno-renal shunt underwent shunt embolization using an Amplatzer vascular plug 2 (AVP2) and metallic coils. The preloading coil in plug method (p-CIP), which facilitated embolization inside the AVP2 without cannulation from outside, was employed to overcome technical difficulties. We propose the use of p-CIP with an AVP2 as a tool for treatment of hepatic encephalopathy with PSS.

Bile Duct Ligation Upregulates Expression and Function of L-Amino Acid Transporter 1 at Blood-Brain Barrier of Rats via Activation of Aryl Hydrocarbon Receptor by Bilirubin

Liver failure is associated with increased levels of brain aromatic amino acids (AAAs), whose transport across the blood–brain barrier (BBB) is mainly mediated by L-amino acid transporter 1 (LAT1). We aimed to investigate whether liver failure induced by bile duct ligation (BDL) increases levels of brain AAAs by affecting the expression and function of LAT1. The LAT1 function was assessed using the brain distribution of gabapentin. It was found that BDL significantly increased levels of gabapentin, phenylalanine, and tryptophan in the cortex, hippocampus, and striatum of rats, and upregulated the expression of total LAT1 protein in hippocampus and striatum as well as cortex membrane LAT1 protein. HCMEC/D3 served as in vitro BBB model, and the data showed that both the serum of BDL rats and bilirubin induced LAT1 expression and function, while bilirubin oxidase almost abolished the upregulation of LAT1 protein by bilirubin and the serum of BDL rats. The enhanced function and expression of LAT1 were also observed in the hippocampus and striatum of hyperbilirubinemia rats. Both aryl hydrocarbon receptor (AhR) antagonist α-naphthoflavone and AhR silencing obviously attenuated the upregulation of LAT1 protein by bilirubin or omeprazole. This study provides the first evidence that BDL upregulates LAT1 at the rat BBB, attributed to the activation of AhR by the increased plasma bilirubin. The results highlight the mechanisms causing BDL-increased levels of brain AAAs and their physiological significance.

Pathological Significance and Prognostic Roles of Indirect Bilirubin/Albumin Ratio in Hepatic Encephalopathy

Background and Aim: Hepatic encephalopathy (HE) is a neurological disease caused by severe liver disease. Early identification of the risk factor is beneficial to the prevention and treatment of HE. Free bilirubin has always been considered to be the culprit of neonatal kernicterus, but there is no research to explore its role in HE. In this study, we aim to study the clinical significance of the indirect bilirubin-albumin ratio in HE.

Methods: A retrospective case-control study of 204 patients with liver failure was conducted. Human serum albumin (HSA) or heme oxygenase-1 (HO-1) inhibitor SnPP (Tin protoporphyrin IX dichloride) was injected intraperitoneally into Ugt1^−/− mice to establish a treatment model for endogenous hyperbilirubinemia.

Results: IBil/albumin ratio (OR = 1.626, 95% CI1.323–2.000, P < 0.001), white blood cell (WBC) (OR = 1.128, 95% CI 1.009–1.262, P = 0.035), ammonia (OR = 1.010, 95% CI 1.001–1.019, P = 0.027), platelet (OR=1.008, 95% CI 1.001–1.016, P = 0.022), Hb (OR = 0.977, 95% CI 0.961–0.994, P = 0.007), and PTA (OR = 0.960, 95% CI 0.933–0.987, P = 0.005) were independent factors of HE. Patients with a history of liver cirrhosis and severe HE (OR = 12.323, 95% CI 3.278–47.076, P < 0.001) were more likely to die during hospitalization. HSA or SnPP treatment improved cerebellum development and reduced apoptosis of cerebellum cells.

Conclusion: The IBil/albumin ratio constitutes the most powerful risk factor in the occurrence of HE, and reducing free bilirubin may be a new strategy for HE treatment.

Ashwagandha (Withania somnifera) root extract attenuates hepatic and cognitive deficits in thioacetamide-induced rat model of hepatic encephalopathy via induction of Nrf2/HO-1 and mitigation of NF-κB/MAPK signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Ashwagandha (ASH) is one of the medicinal plants used in traditional Indian, Ayurvedic, and Unani medicines for their broad range of pharmacological activities including, tonic, aphrodisiac, energy stimulant, and counteracting chronic fatigue. Besides, it is used in the treatment of nervous exhaustion, memory-related conditions, insomnia, as well as improving learning ability and memory capacity. ASH is preclinically proven to be efficient in hepatoprotection and improving cognitive impairment, however, its beneficial effects against hepatic encephalopathy (HE) is still unclear. Therefore, this study aimed at investigating the protective effects of ASH root extract against thioacetamide (TAA)-induced HE and delineate the underlying behavioral and pharmacological mechanisms.

MATERIALS AND METHODS

ASH metabolites were identified using UPLC-HRMS. Rats were pretreated with ASH (200 and 400 mg/kg) for 29 days and administrated TAA (i.p, 350 mg/kg) in a single dose. Then, behavioral (open field test, Y-maze, modified elevated plus maze and novel object recognition test), and biochemical (ammonia and hepatic toxicity indices) assessments, as well as oxidative stress markers (MDA and GSH) were evaluated. The hepatic and brain levels of glutamine synthetase (GS), nuclear factor erythroid 2-related factor 2 (Nrf2), heme-oxygenase (HO)-1, inducible nitric oxide synthase (iNOS) were detected by enzyme-linked immunosorbent assay (ELISA). The mRNA expressions of p38/ERK½ were determined using real-time polymerase chain reaction (PCR). Moreover, histopathological investigations and immunohistochemical (NF-κB and TNF-α immunohistochemical expressions) examinations were performed.

RESULTS

Metabolite profiling of ASH revealed more than 45 identified metabolites including phenolic acids, flavonoids and steroidal lactone triterpenoids. Compared to the TAA-intoxicated group, ASH improved the locomotor and cognitive deficits, serum hepatotoxicity indices and ammonia levels, as well as brain and hepatic histopathological alterations. ASH reduced hepatic and brain levels of MDA, GS, and iNOS, and increased their GSH, Nrf2, and HO-1 levels. Also, ASH downregulated p38 and ERK½ mRNA expressions, and NF-κB and TNF-α immunohistochemical expressions in brain and hepatic tissues.

CONCLUSIONS

Our results provided insights into the promising hepato- and neuroprotective effects of ASH, with superiority to 400 mg/kg ASH, to ameliorate HE with its sequential hyperammonemia and liver/brain injuries. This could be attributed to the recorded increase in the spontaneous alternation % and recognition index, antioxidant and anti-inflammatory activities, as well as upregulation of Nrf2 and downregualtion of MAPK signaling pathways.

Standardization of the psychometric hepatic encephalopathy score in a French population

The Psychometric Hepatic Encephalopathy Score (PHES) has previously been standardized in thirteen countries on three continents, confirming its status of gold standard test to detect minimal hepatic encephalopathy (MHE). In the meantime, performance has also been shown to vary with variables such as age, education, and barely sex. The present study aimed at standardizing the PHES in a French population. One hundred and ninety-six French healthy participants completed a French version of the paper-and-pencil PHES, involving five tests and six measures. Importantly, the balance was perfect between all levels of the three controlled factors, which were sex, age (seven decade-levels from 20–29 to 80–89 years), and education (two levels below or above 12 years of education). Raw measures were transformed to fit the normal distribution. ANOVAs on transformed variables showed no effect of sex, but an effect of age on all measures, and of education on five measures. Multiple or simple regressions were completed to build up normograms. Thorough analysis of variability within each test failed to find outliers that may bias the results. Comparison between French and seminal German data showed that they highly fitted though cultural and cognitive style specificities could be observed. This is the first study to standardize the PHES in a French population and to extensively explore the effects of sex, age and education using perfectly balanced samples. Subtle differences between countries of the same continent emphasize the need to build up normative data in each country to get accurate PHES in patients.

Progress in research of blood oxygen level dependent functional magnetic resonance imaging in cirrhotic patients with minimal hepatic encephalopathy

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome that develops in patients with cirrhosis or other severe liver diseases. The incidence of minimal hepatic encephalopathy (MHE) is high, and MHE is often misdiagnosed because of its subclinical manifestations. MHE significantly reduces patients' quality of life and its prognosis is poor. Blood oxygen level dependent functional magnetic resonance imaging (BOLD-fMRI) has been used to explore the brain functional changes and to further understand pathophysiological mechanisms of brain disease. This article focuses on the progress in the research of BOLD-fMRI in cirrhotic patients with MHE with regard to its principles, categories, and post-processing algorithms.

Therapeutic Applications of Resveratrol in Hepatic Encephalopathy through Its Regulation of the Microbiota, Brain Edema, and Inflammation

Hepatic encephalopathy is a common complication in patients with liver cirrhosis and portosystemic shunting. Patients with hepatic encephalopathy present a variety of clinical features, including neuropsychiatric manifestations, cognitive dysfunction, impaired gut barrier function, hyperammonemia, and chronic neuroinflammation. These pathogeneses have been linked to various factors, including ammonia-induced oxidative stress, neuronal cell death, alterations in the gut microbiome, astrocyte swelling, and blood-brain barrier disruptions. Many researchers have focused on identifying novel therapeutics and prebiotics in the hope of improving the treatment of these conditions. Resveratrol is a natural polyphenic compound and is known to exert several pharmacological effects, including antioxidant, anti-inflammatory, and neuroprotective activities. Recent studies suggest that resveratrol contributes to improving the neuropathogenic effects of liver failure. Here, we review the current evidence describing resveratrol's effects in neuropathogenesis and its impact on the gut-liver axis relating to hepatic encephalopathy. We highlight the hypothesis that resveratrol exerts diverse effects in hepatic encephalopathy and suggest that these effects are likely mediated by changes to the gut microbiota, brain edema, and neuroinflammation.

Movement Disorders and Liver Disease

The association of movement disorders with structural or functional hepatic disease occurs in three principal scenarios: (1) combined involvement of both organ systems from a single disease entity, (2) nervous system dysfunction resulting from exposure to toxic compounds in the setting of defective hepatic clearance, or (3) hepatic and/or neurological injury secondary to exposure to exogenous drugs or toxins. An important early step in the workup of any patient with combined movement disorders and liver disease is the exclusion of Wilson's disease. Diagnostic delay remains common for this treatable disorder, and this has major implications for patient outcomes. Thereafter, a structured approach integrating variables such as age of onset, tempo of progression, nature and severity of liver involvement, movement disorder phenomenology, exposure to drugs/toxins and laboratory/neuroimaging findings is key to ensuring timely diagnosis and disease‐specific therapy. Herein, we provide an overview of disorders which may manifest with a combination of movement disorders and liver disease, structured under the three headings as detailed above. In each section, the most common disorders are discussed, along with important clinical pearls, suggested diagnostic workup, differential diagnoses and where appropriate, treatment considerations.

The prognosis and incidence of hepatic encephalopathy of patients with liver cirrhosis treated with proton pump inhibitors: A multicenter retrospective study in Japan

Gastrointestinal bleeding, hepatic encephalopathy (HE), and hepatocarcinogenesis are associated with the prognosis of patients with liver cirrhosis (LC). Proton pump inhibitors (PPIs) have been used to prevent bleeding, however the effects of PPIs on overall survival have not yet been elucidated. Therefore, this multicenter retrospective study aimed to assess the effect of PPI on the prognosis and HE occurrence of the patients with liver cirrhosis in Japan.A total of 456 patients diagnosed with LC at the 4 institutes during the study period (2010-2014) were assessed. PPI-treated and non-treated patients were compared using propensity score matching analysis. Primary and secondary endpoints of the study were set as the occurrence of HE and overall survival, respectively.A comparison of all cases showed a significantly poorer hepatic reserve function in the PPI-treated patients. The propensity-score matching analysis was performed and 120 PPI-treated patients were 1:1 matched with non-treated patients. The analysis revealed a higher incidence of HE in the PPI-treated than in the non-treated patients (P = .032; hazard ratio [HR], 2.162; 95% confidence interval [CI], 1.066-4.176), but the prognosis of PPI-treated patients was no worse than that of non-treated patients (P = .676; HR, 1.101; 95% CI, 0.702-1.726).This retrospective study showed that PPI administration for the patients with liver cirrhosis may partly be related to the increased incidence of HE but not worsen the patient prognosis.

Liver and Biliary Disease of Pregnancy and Anesthetic Implications: A Review

Liver and biliary disease complicates pregnancy in varying degrees of severity to the mother and fetus, and anesthesiologists may be asked to assist in caring for these patients before, during, and after birth of the fetus. Therefore, it is important to be familiar with how different liver diseases impact the pregnancy state. In addition, knowing symptoms, signs, and laboratory markers in the context of a pregnant patient will lead to faster diagnosis and treatment of such patients. This review article discusses changes in physiology of parturients, patients with liver disease, and parturients with liver disease. Next, general treatment of parturients with acute and chronic liver dysfunction is presented. The article progresses to specific liver diseases with treatments as they relate to pregnancy. And finally, important aspects to consider when anesthetizing parturients with liver disease are discussed.

Copper, Iron, and Manganese Toxicity in Neuropsychiatric Conditions

Copper, manganese, and iron are vital elements required for the appropriate development and the general preservation of good health. Additionally, these essential metals play key roles in ensuring proper brain development and function. They also play vital roles in the central nervous system as significant cofactors for several enzymes, including the antioxidant enzyme superoxide dismutase (SOD) and other enzymes that take part in the creation and breakdown of neurotransmitters in the brain. An imbalance in the levels of these metals weakens the structural, regulatory, and catalytic roles of different enzymes, proteins, receptors, and transporters and is known to provoke the development of various neurological conditions through different mechanisms, such as via induction of oxidative stress, increased α-synuclein aggregation and fibril formation, and stimulation of microglial cells, thus resulting in inflammation and reduced production of metalloproteins. In the present review, the authors focus on neurological disorders with psychiatric signs associated with copper, iron, and manganese excess and the diagnosis and potential treatment of such disorders. In our review, we described diseases related to these metals, such as aceruloplasminaemia, neuroferritinopathy, pantothenate kinase-associated neurodegeneration (PKAN) and other very rare classical NBIA forms, manganism, attention-deficit/hyperactivity disorder (ADHD), ephedrone encephalopathy, HMNDYT1-SLC30A10 deficiency (HMNDYT1), HMNDYT2-SLC39A14 deficiency, CDG2N-SLC39A8 deficiency, hepatic encephalopathy, prion disease and “prion-like disease”, amyotrophic lateral sclerosis, Huntington’s disease, Friedreich’s ataxia, and depression.

SOFAMONIA: Comparison of the original SOFA score with the proposed new score including serum ammonia

Introduction:

Hyperammonemia can represent organic dysfunction of the brain, kidney, or liver. Evaluation of serum ammonia concentrations as a parameter for organ dysfunction may be justified.

Objective:

To evaluate the performance of serum ammonia as an additional or substitute variable for organ systems in the Sequential Organ Failure Assessment (SOFA) score.

Methods:

A prospective cohort study including 173 patients admitted to the intensive care unit between March 2015 and February 2016. SOFAMONIA scores were defined as follows: SOFAMONIA1 (Glasgow coma scale replaced by serum ammonia), SOFAMONIA2 (serum bilirubin replaced by serum ammonia), SOFAMONIA3 (renal system score replaced by serum ammonia), and SOFAMONIA4 (addition of serum ammonia to the original SOFA as the seventh variable, changing the maximum score from 24 to 28).

Results:

The original SOFA presented an area under the curve–receiver operating characteristic of 0.697 to predict hospital mortality. There was a positive correlation between SOFA and SOFAMONIA scores. SOFAMONIA1 presented a cut-off point of 5 for area under the curve 0.684 (0.610–0.753, 95% confidence interval), SOFAMONIA2 presented a cut-off point of 9 for area under the curve 0.701 (0.626–0.768, 95% confidence interval), SOFAMONIA3 presented a cut-off point of 8 for area under the curve 0.674 (0.598–0.743, 95% confidence interval), and SOFAMONIA4 presented a cut-off point of 8 for area under the curve 0.702 (0.628–0.769, 95% confidence interval).

Conclusions:

The addition of ammonia as the seventh parameter of the SOFA score showed the best performance to predict hospital mortality. The addition of ammonia as a representative of metabolic dysfunction may be useful in the follow-up of critically ill patients.

Additional L-Carnitine Reduced the Risk of Hospitalization in Patients with Overt Hepatic Encephalopathy on Rifaximin

BACKGROUND

Data regarding the additional effect on the recurrence of hepatic encephalopathy (HE) after oral L-carnitine administration are scarce.

OBJECTIVE

This study aimed to assess the additional effects of L-carnitine in patients who were receiving rifaximin for HE.

METHODS

This randomized study comprised a screening visit and a 12-week treatment period. Patients who fulfilled the eligibility criteria were randomized to either group A (additional rifaximin) or group B (additional L-carnitine and rifaximin). Group A received 1,200 mg/day of rifaximin. Group B received 1,500 mg/day of L-carnitine and rifaximin at 1,200 mg/day. The endpoints were the changes in the portal systemic encephalopathy (PSE) index and the admission rate from the baseline for the duration of the study in both groups.

RESULTS

Eighty-three patients were randomized to either group A (n = 42) or group B (n = 41). In group A, the PSE index decreased from 0.35 ± 0.09 at baseline to 0.27 ± 0.11 on the final evaluation day (p = 0.001). In group B, the PSE index decreased from 0.37 ± 0.09 at baseline to 0.24 ± 0.11 on the final evaluation day (p = 0.001). Although there was not a significant reduction in the PSE index in group A compared to that in group B (p = 0.202), the admission rates were 30.9% and 9.8% in groups A and B, respectively. Additional L-carnitine significantly reduced the admission rate (p = 0.028).

CONCLUSION

L-Carnitine addition reduced the risk of hospitalization for patients who received rifaximin for HE.

An extracorporeal bioartificial liver embedded with 3D-layered human liver progenitor-like cells relieves acute liver failure in pigs

Clinical advancement of the bioartificial liver is hampered by the lack of expandable human hepatocytes and appropriate bioreactors and carriers to encourage hepatic cells to function during extracorporeal circulation. We have recently developed an efficient approach for derivation of expandable liver progenitor-like cells from human primary hepatocytes (HepLPCs). Here, we generated immortalized and functionally enhanced HepLPCs by introducing FOXA3, a hepatocyte nuclear factor that enables potentially complete hepatic function. When cultured on macroporous carriers in an air-liquid interactive bioartificial liver (Ali-BAL) support device, the integrated cells were alternately exposed to aeration and nutrition and grew to form high-density three-dimensional constructs. This led to highly efficient mass transfer and supported liver functions such as albumin biosynthesis and ammonia detoxification via ureagenesis. In a porcine model of drug overdose-induced acute liver failure (ALF), extracorporeal Ali-BAL treatment for 3 hours prevented hepatic encephalopathy and led to markedly improved survival (83%, n = 6) compared to ALF control (17%, n = 6, P = 0.02) and device-only (no-cell) therapy (0%, n = 6, P = 0.003). The blood ammonia concentrations, as well as the biochemical and coagulation indices, were reduced in Ali-BAL-treated pigs. Ali-BAL treatment attenuated liver damage, ameliorated inflammation, and enhanced liver regeneration in the ALF porcine model and could be considered as a potential therapeutic avenue for patients with ALF.

Fecal Microbiota Transplantation in Patients with HBV Infection or Other Chronic Liver Diseases: Update on Current Knowledge and Future Perspectives

Liver disease and gut dysbiosis are strictly associated, and the pathophysiology of this bidirectional relationship has recently been the subject of several investigations. Growing evidence highlights the link between gut microbiota composition, impairment of the gut-liver axis, and the development or progression of liver disease. Therefore, the modulation of gut microbiota to maintain homeostasis of the gut-liver axis could represent a potential instrument to halt liver damage, modify the course of liver disease, and improve clinical outcomes. Among all the methods available to achieve this purpose, fecal microbiota transplantation (FMT) is one of the most promising, being able to directly reshape the recipient’s gut microbial communities. In this review, we report the main characteristics of gut dysbiosis and its pathogenetic consequences in cirrhotic patients, discussing the emerging data on the application of FMT for liver disease in different clinical settings.

Fiber scaffold bioartificial liver therapy relieves acute liver failure and extrahepatic organ injury in pigs

Rationale: Acute liver failure (ALF) causes severe liver injury and a systemic inflammatory response, leading to multiorgan failure with a high short-term mortality. Bioartificial liver (BAL) therapy is a promising approach that is hampered by the lack of appropriate bioreactors and carriers to retain hepatic cell function and poor understanding of BAL treatment mechanisms in ALF and extrahepatic organ injury. Recently, we used a fiber scaffold bioreactor (FSB) for the high-density, three-dimensional (3D) culture of primary porcine hepatocytes (PPHs) combined with an absorption component to construct a BAL and verified its function in a D-galactosamine (D-gal)-induced ALF porcine model to evaluate its protective effects on the liver and extrahepatic organs. Methods: Male pigs were randomized into standard/supportive therapy (ST), ST+no-cell BAL (ST+Sham BAL) and ST+BAL groups and received treatment 48 h after receiving a D-gal injection. Changes in blood chemistry and clinical symptoms were monitored for 120 h. Tissues and plasma were collected for analysis by pathological examination, immunoblotting, quantitative PCR and immunoassays. Results: PPHs cultured in the FSB obtained sufficient aeration and nutrition for high-density, 3D culture and maintained superior viability and functionality (biosynthesis and detoxification) compared with those cultured in flasks. All the animals developed ALF, acute kidney injury (AKI) and hepatic encephalopathy (HE) 48 h after D-gal infusion and received corresponding therapies. Animals in the BAL group showed markedly improved survival (4/5; 80%) compared with those in the ST+Sham BAL (0/5; p < 0.001) and ST (0/5; p < 0.001) groups. The levels of blood ammonia and biochemical and inflammatory indices were alleviated after BAL treatment. Increased liver regeneration and attenuations in the occurrence and severity of ALF, AKI and HE were observed in the ST+BAL group compared with the ST (p = 0.0009; p = 0.038) and ST+Sham BAL (p = 0.011; p = 0.031) groups. Gut leakage, the plasma endotoxin level, bacterial translocation, and peripheral and neuroinflammation were alleviated in the ST+BAL group compared with those in the other groups. Conclusions: BAL treatment enhanced liver regeneration and alleviated the systemic inflammatory response and extrahepatic organ injury to prolong survival in the ALF model and has potential as a therapeutic approach for ALF patients.

Development and Validation of a Clinical-Genetic Risk Score to Predict Hepatic Encephalopathy in Patients With Liver Cirrhosis

INTRODUCTION

We aimed to define the impact of the genetic background on overt hepatic encephalopathy (HE) in patients with liver cirrhosis by developing a combined clinical-genetic risk score.

METHODS

Patients suffering from liver cirrhosis from the outpatient clinics of 4 hospitals (n = 600) were included and followed up for at least 5 years until HE bouts, liver transplant, or death. Patients were genotyped for 60 candidate single nucleotide polymorphisms together with the microsatellite in the promoter region of the gene GLS.

RESULTS

Single nucleotide polymorphisms rs601338 (FUT2), rs5743836 (TRL9), rs2562582 (SLC1A3), rs313853 (SLC1A5), and GLS microsatellite did predict independently the incidence and severity of overt HE and were included as genetic score. Competing risk analysis revealed that bilirubin (subhazard ratio [sHR] 1.30 [1.15-1.48], P < 0.001), albumin (sHR 0.90 [0.86-0.93], P < 0.001), genetic score (sHR 1.90 [1.57-2.30], P < 0.001), and previous episodes of overt HE (sHR 2.60 [1.57-4.29], P < 0.001) were independently associated to HE bouts during the follow-up with an internal (C-index 0.83) and external validation (C-index 0.74). Patients in the low-risk group had 5% and 12% risk of HE at 1 (log-rank 92.1; P < 0.001) and 5 (log-rank 124.1; P < 0.001) years, respectively, whereas 36% and 48% in the high-risk group.

DISCUSSION

The genetic background influenced overt HE risk and severity. The clinical-genetic HE Risk score, which combined genetic background together with albumin, bilirubin, and previous episodes of overt HE, could be a useful tool to predict overt HE in patients with cirrhosis.

Real-World Experience of the One-Year Efficacy of Rifaximin Add-On to Lactulose Is Superior to Lactulose Alone in Patients with Cirrhosis Complicated with Recurrent Hepatic Encephalopathy in Taiwan

Background: Hepatic encephalopathy (HE), a neuropsychiatric complication of decompensated cirrhosis, is associated with high mortality and high risk of recurrence. Rifaximin add-on to lactulose for 3 to 6 months is recommended for the prevention of recurrent episodes of HE after the second episode. However, whether the combination for more than 6 months is superior to lactulose alone in the maintenance of HE remission is less evident. Therefore, the aim of this study is to evaluate the one-year efficacy of rifaximin add-on to lactulose for the maintenance of HE remission in Taiwan. Methods: We conducted a real-world single-center retrospective cohort study to compare the long-term efficacy of rifaximin add-on to lactulose (group R + L) versus lactulose alone (group L, control group). Furthermore, the treatment efficacy before and after rifaximin add-on to lactulose was also analyzed. The primary endpoint of our study was time to first HE recurrence (Conn score ≥ 2). All patients were followed up every three months until death, and censored at one year if still alive. Results and Conclusions: 12 patients were enrolled in group R + L. Another 31 patients were stratified into group L. Sex, comorbidity, ammonia level, and ascites grade were matched while age, HE grade, and model for end-stage liver disease (MELD) score were adjusted in the multivariable logistic regression model. Compared with group L, significant improvement in the maintenance of HE remission and decreased episodes and days of HE-related hospitalizations were demonstrated in group R + L. The serum ammonia levels were significantly lower at the 3rd and 6th month in group 1. Concerning changes before and after rifaximin add-on in group R + L, mini-mental status examination (MMSE), episodes of hospitalization, and variceal bleeding also improved at 6 and 12 months. Days of hospitalization, serum ammonia levels also improved at 6th month. Except for concern over price, no patients discontinued rifaximin due to adverse events or complications. The above results provide evidence for the one-year use of rifaximin add-on to lactulose in reducing HE recurrence and HE-related hospitalization for patients with decompensated cirrhosis.

Step by Step: Managing the Complications of Cirrhosis

According to the Centers for Disease Control and Prevention, chronic liver disease and cirrhosis is the 11th leading cause of death in the United States. Common causes of chronic liver disease include alcohol, viral hepatitis, and non-alcoholic steatohepatitis (NASH). Inflammation is a critical driver in the progression of liver disease to liver fibrosis and ultimately cirrhosis. While the severity of chronic liver disease extends over a continuum, the management is more easily differentiated between compensated and decompensated cirrhosis. In this review, we discuss pathophysiology, clinical features and management of common complications of liver cirrhosis based on literature review and the current clinical practice guidelines of the American Association for the Study of Liver Diseases (AASLD).

The Role of the Microbiome in Liver Cancer

Hepatocellular carcinoma (HCC) is the most common malignancy occuring in the context of chronic liver disease and is one of the main causes of cancer-derived death worldwide. The lack of effective treatments, together with the poor prognosis, underlines the urge to develop novel and multidisciplinary therapeutics. An increasing body of evidence shows that HCC associates with changes in intestinal microbiota abundance and composition as well as with impaired barrier function, leading to the release of bacteria and their metabolites to the liver. These factors trigger a cascade of inflammatory responses contributing to liver cirrhosis and constituting an ideal environment for the progression of HCC. Interestingly, the use of bacteriotherapy in human and preclinical studies of chronic liver disease and HCC has been shown to successfully modify the microbiota composition, reducing overall inflammation and fibrosis. In this review, we explore the existing knowledge on the characterisation of the intestinal microbial composition in humans and experimental murine chronic liver disease and HCC, as well as the use of antibiotics and bacteriotherapy as therapeutic options.

Fecal microbiota transplantation in hepatic encephalopathy: a systematic review

Hepatic encephalopathy (HE) is a reversible neurocognitive dysfunction that ranges in severity from subclinical alterations to coma. Patients with chronic liver disease are predisposed to HE due to metabolic failure and portosystemic shunting of toxins, of which ammonia is believed to be the main toxic chemical. Fecal microbiota transplantation (FMT) may reduce ammonia synthesis by altering the gut microbiota composition to a taxon low in urease, diminish uptake of ammonia by reestablishing the integrity of the intestinal barrier and increase ammonia clearance by improving liver function. In this systematic review, we summarize the insights of the current literature examining FMT as a treatment for HE.PubMed and EMBASE were searched on 08 February 2021 using the MeSH terms 'fecal microbiota transplantation & hepatic encephalopathy' and the abbreviations 'FMT & HE'.Eight studies fulfilled our inclusion criteria, comprising two randomized clinical trials, three case reports and three rodent studies. Thirty-nine patients with HE were treated with FMT. Thirty-nine rodents received FMT in laboratory tests. FMT improved neurocognitive test results in four human studies and two rodent studies. Microbiota originating from donors was found in human recipients one year post-FMT. Readmission of patients was lower after treatment with FMT compared to standard of care.FMT may improve neurocognitive function and reduce serious adverse events in patients with HE, but the studies conducted so far have been small and their long-term follow-up is limited. Large-scale, randomized and controlled trials are needed to validate and help standardize the clinical application of FMT in cases of HE.

The pathophysiological function of non-gastrointestinal farnesoid X receptor

Farnesoid X receptor (FXR) influences bile acid homeostasis and the progression of various diseases. While the roles of hepatic and intestinal FXR in enterohepatic transport of bile acids and metabolic diseases were reviewed previously, the pathophysiological functions of FXR in non-gastrointestinal cells and tissues have received little attention. Thus, the roles of FXR in the liver, immune system, nervous system, cardiovascular system, kidney, and pancreas beyond the gastrointestinal system are reviewed herein. Gain of FXR function studies in non-gastrointestinal tissues reveal that FXR signaling improves various experimentally-induced metabolic and immune diseases, including non-alcoholic fatty liver disease, type 2 diabetes, primary biliary cholangitis, sepsis, autoimmune diseases, multiple sclerosis, and diabetic nephropathy, while loss of FXR promotes regulatory T cells production, protects the brain against ischemic injury, atherosclerosis, and inhibits pancreatic tumor progression. The downstream pathways regulated by FXR are diverse and tissue/cell-specific, and FXR has both ligand-dependent and ligand-independent activities, all of which may explain why activation and inhibition of FXR signaling could produce paradoxical or even opposite effects in some experimental disease models. FXR signaling is frequently compromised by diseases, especially during the progressive stage, and rescuing FXR expression may provide a promising strategy for boosting the therapeutic effect of FXR agonists. Tissue/cell-specific modulation of non-gastrointestinal FXR could influence the treatment of various diseases. This review provides a guide for drug discovery and clinical use of FXR modulators.

Connecting the dots: Targeting the microbiome in drug toxicity

The gut microbiota has a vast influence on human health and its role in initiating, aggravating, or ameliorating diseases is beginning to emerge. Recently, its contribution to heterogeneous toxicological responses is also gaining attention, especially in drug-induced toxicity. Whether they are orally administered or not, drugs may interact with the gut microbiota directly or indirectly, which leads to altered toxicity. Present studies focus more on the unidirectional influence of how xenobiotics disturb intestinal microbial composition and functions, and thus induce altered homeostasis. However, interactions between the gut microbiota and xenobiotics are bidirectional and the impact of the gut microbiota on xenobiotics, especially on drugs, should not be neglected. Thus, in this review, we focus on how the gut microbiota modulates drug toxicity by highlighting the microbiome, microbial enzyme, and microbial metabolites. We connect the dots between drugs, the microbiome, microbial enzymes or metabolites, drug metabolites, and host toxicological responses to facilitate the discovery of microbial targets and mechanisms associated with drug toxicity. Besides this, current mainstream strategies to manipulate drug toxicity by targeting the microbiome are summarized and discussed. The review provides technical reference for the evaluation of medicinal properties in the research and development of innovative drugs, and for the future exploitation of strategies to reduce drug toxicity by targeting the microbiome.

Mahuang Decoction Antagonizes Acute Liver Failure via Modulating Tricarboxylic Acid Cycle and Amino Acids Metabolism

Acute liver failure (ALF) is a serious clinical disorder with high fatality rates. Mahuang decoction (MHD), a well-known traditional Chinese medicine, has multiple pharmacological effects, such as anti-inflammation, anti-allergy, anti-asthma, and anti-hyperglycemia. In this study, we investigated the protective effect of MHD against ALF. In the lipopolysaccharide and D-galactosamine (LPS/D-GalN)-induced ALF mouse model, the elevated activities of the serum alanine and aspartate transaminases as well as the liver pathological damage were markedly alleviated by MHD. Subsequently, a metabolomics study based on the ultrahigh performance liquid chromatograph coupled with Q Exactive Orbitrap mass spectrometry was carried to clarify the therapeutic mechanisms of MHD against ALF. A total of 36 metabolites contributing to LPS/D-GalN-induced ALF were identified in the serum samples, among which the abnormalities of 27 metabolites were ameliorated by MHD. The analysis of metabolic pathways revealed that the therapeutic effects of MHD are likely due to the modulation of the metabolic disorders of tricarboxylic acid (TCA) cycle, retinol metabolism, tryptophan metabolism, arginine and proline metabolism, nicotinate and nicotinamide metabolism, phenylalanine metabolism, phenylalanine, tyrosine and tryptophan synthesis, as well as cysteine and methionine metabolism. This study demonstrated for the first time that MHD exerted an obvious protective effect against ALF mainly through the regulation of TCA cycle and amino acid metabolism, highlighting the importance of metabolomics to investigate the drug-targeted metabolic pathways.

Systemic Artery Vasoconstrictor Therapy in Fontan Patients with High Cardiac Output-Heart Failure: A Single-Center Experience

Failed Fontan Patients with high cardiac output (CO) heart failure (HF) might have vasodilatory syndrome and markedly high mortality rates. The aim of this study was to review the clinical effects of vasoconstrictor therapy (VCT) for failed Fontan hemodynamics. We retrospectively reviewed 10 consecutive patients with Fontan failure (median age, 33 years) and high CO-HF who had received VCT. The hemodynamics were characterized by high central venous pressure (CVP: median, 16 mm Hg), low systolic blood pressure (median, 83 mm Hg), low systemic vascular resistance (median, 8.8 U·m²), high cardiac index (median, 4.6 L/min/m²), and low arterial oxygen saturation (median, 89%). VCT included intravenous noradrenaline infusion for five unstable patients, oral midodrine administration for nine stable patients, and both for four patients. After VCT introduction with a median interval of 1.7 months, the median systolic blood pressure (102 mm Hg, p = 0.004), arterial oxygen saturation (90%, p = 0.03), and systemic vascular resistance (12.1 U·m², p = 0.13) increased without significant changes in CVP or cardiac index. After a median follow-up of 21 months, the number of readmissions per year decreased from 4 (1-11) to 1 (0-9) (p = 0.25), and there were no VCT-related complications; however, five patients (50%) developed hepatic encephalopathy, and six patients (60%) eventually died. VCT was safely introduced and could prevent the rapidly deteriorating Fontan hemodynamics. VCT could be an effective therapeutic strategy for failed Fontan patients with high CO-HF.

Associations of Serum Liver Function Markers With Brain Structure, Function, and Perfusion in Healthy Young Adults

Background: Previous neuroimaging studies have demonstrated brain abnormalities in patients with hepatic diseases. However, the identified liver-brain associations are largely limited to disease-affected populations, and the nature and extent of such relations in healthy subjects remain unclear. We hypothesized that serum liver function markers within a normal level would affect brain properties. Method: One hundred fifty-seven healthy young adults underwent structural, resting-state functional, and arterial spin labeling MRI scans. Gray matter volume (GMV), regional homogeneity (ReHo), and cerebral blood flow (CBF) analyses were performed to assess brain structure, function, and perfusion, respectively. Peripheral venous blood samples were collected to measure serum liver function markers. Correlation analyses were conducted to test potential associations between liver function markers and brain imaging parameters. Results: First, serum proteins showed relations to brain structure characterized by higher albumin associated with increased GMV in the parahippocampal gyrus and amygdala and lower globulin and a higher albumin/globulin ratio with increased GMV in the olfactory cortex and parahippocampal gyrus. Second, serum bilirubin was linked to brain function characterized by higher bilirubin associated with increased ReHo in the precuneus, middle cingulate gyrus, inferior parietal lobule, and supramarginal gyrus and decreased ReHo in the caudate nucleus. Third, serum alanine transaminase (ALT) was related to brain perfusion characterized by higher ALT associated with increased CBF in the superior frontal gyrus and decreased CBF in the middle occipital gyrus, angular gyrus, precuneus, and middle temporal gyrus. More importantly, we found that CBF in the superior frontal gyrus was a significant mediator of the association between serum ALT level and working memory performance. Conclusion: These findings may not only expand existing knowledge about the relationship between the liver and the brain but also have clinical implications for studying brain impairments secondary to liver diseases as well as providing potential neural targets for their diagnosis and treatment.

Altered intrinsic brain activity in patients with hepatic encephalopathy

Neuropsychiatric deficits are common in patients with liver cirrhosis (LC), especially in those with hepatic encephalopathy (HE). Previous studies reveal abnormalities in brain activity underlying the neuropsychiatric deficits in LC patients; however, the results are inconsistent. We conducted a meta-analysis of resting-state functional magnetic resonance imaging studies using anisotropic effect-size signed differential mapping software on LC patients to characterize the most consistent regional activity alterations, and to evaluate the potential effect of liver transplantation (LT) on brain function. Meta-regression analyses were performed to explore the relationship between brain alterations and clinical variables. Compared with healthy controls, the typical patterns of increased regional activity in the fronto-striato-cerebellar network and decreased activity in the visuo-sensorimotor network and cingulate gyrus were identified in LC patients, which remained significant in the subgroup meta-analyses of minimal HE (MHE) and overt HE (OHE) patients. Functional deficits in the default mode network (DMN) were found in OHE patients compared with MHE patients. Ammonia level positively correlated with brain activity in the right middle temporal gyrus, and the completion time of number connection test A negatively correlated with brain activity in the left anterior cingulate gyrus. In addition, patients showed increased activity in the visuo-sensorimotor network and precuneus after LT. Our study suggests that alterations in the fronto-striato-cerebellar and visuo-sensorimotor networks may be the potential pathophysiological mechanisms underlying HE, and deficits in the DMN may indicate the progression of HE. LT may improve brain function in the visuo-sensorimotor network. This study has registered in the PROSPERO (CRD42020212758).

Nursing Management of Hepatic Encephalopathy

This article provides a background of hepatic encephalopathy, its relation to liver disease as well as its prevalence in the United States. A literature review provides an overview of HE discussing the pathophysiology, evidence-based diagnosis, and grading of the disease severity as well as treatment options and interventions. A large emphasis of the article is placed on nursing's role of identifying and managing hepatic encephalopathy. The authors hope to provide clinical nurses with the tools and information needed to provide evidence-based care to this patient population. Pharmacologic therapies, as well as nutrition for these patients, are other topics reviewed. Education for nurses on the management of hepatic encephalopathy is important, as well as education needed for patients and families to support them through the treatment and follow-up care needed to manage hepatic encephalopathy. The authors also hope to provide nurses with education tips to provide the patients and families they care for during their hospitalization with HE, as well as on discharge from the hospital to prevent reoccurrence of symptoms.

A bioartificial liver support system integrated with a DLM/GelMA-based bioengineered whole liver for prevention of hepatic encephalopathy via enhanced ammonia reduction

Although bioartificial liver support systems (BLSSs) play an essential role in maintaining partial liver functions and detoxification for liver failure patients, hepatocytes are unanimously seeded in biomaterials, which lack the hierarchal structures and mechanical cues of native liver tissues. To address this challenge, we developed a new BLSS by combining a decellularized liver matrix (DLM)/GelMA-based bioengineered whole liver and a perfusion-based, oxygenated bioreactor. The novel bioengineered whole liver was fabricated by integrating photocrosslinkable gelatin (GelMA) and hepatocytes into a DLM. The combination of GelMA and the DLM not only provided a biomimetic extracellular microenvironment (ECM) for enhanced cell immobilization and growth with elevated hepatic functions (e.g., albumin secretion and CYP activities), but also provided biomechanical support to maintain the native structure of the liver. In addition, the perfusion-based, oxygenated bioreactor helped deliver oxygen to the interior tissues of the bioengineered liver, which was of importance for long-term culture. Most importantly, this new bioengineered whole liver decreased ammonia concentration by 45%, whereas direct seeding of hepatocytes in a naked DLM showed no significant reduction. Thus, the developed BLSS integrated with the DLM/GelMA-based bioengineered whole liver can potentially help elevate liver functions and prevent HE in liver failure patients while waiting for liver transplantation.

Real-time breath ammonia measurement using a novel cuprous bromide sensor device in patients with chronic liver disease: a feasibility and pilot study

We developed a small portable sensor device using a p-type semiconductor cuprous bromide (CuBr) thin film to measure breath ammonia in real time with highsensitivity and selectivity. Breath ammonia is reportedly associated with chronic liver disease (CLD). We aimed to assess the practical utility of the novel CuBr sensor device for exhaled breath ammonia and the correlation between breath and blood ammonia in CLD patients. This was a feasibility and pilot clinical study of 21 CLD patients and 18 healthy volunteers. Breath ammonia was directly and quickly measured using the novel CuBr sensor device and compared with blood ammonia measured at the same time. CLD patients had significantly higher breath ammonia levels than healthy subjects (p = 1.51 × 10^-3), with the level of significance being similar to that for blood ammonia levels (p= 0.024). Significant differences were found in breath and blood ammonia between the healthy and cirrhosis groups (p = 2.97 × 10^-3 and 3.76 × 10^-3, respectively). Significant, positive correlations between breath and blood ammonia were noted in the CLD group (R = 0.747, p = 1.00 × 10^-4), healthy/CLD group (R = 0.741, p = 6.75 × 10^-8), and cirrhosis group (R = 0.744, p = 9.52 × 10^-4). In conclusion, the newly developed, easy-to-use, and small portable CuBr sensor device was able to non-invasively measure breath ammonia in real time. Breath ammonia measured using the device was correlated with blood ammonia and the presence of liver cirrhosis, and might be an alternative surrogate biomarker to blood ammonia.

L-carnitine reduces hospital admissions in patients with hepatic encephalopathy

AIM

The aim of this study was to determine whether oral L-carnitine administration reduces the blood ammonia concentration and number of hospital admissions for hepatic encephalopathy in patients with advanced cirrhosis.

METHODS

Of 68 patients with hepatic encephalopathy treated with oral L-carnitine supplementation from April 2013 to March 2016, we enrolled 19 patients who had received full standard treatment. We analyzed blood ammonia concentration, number of hospital admissions, and prognosis to determine how effective L-carnitine was in achieving mid-term to long-term suppression of recurrent hepatic encephalopathy.

RESULTS

Median blood ammonia concentrations at the start, 1 week, 12 weeks, 24 weeks, and 48 weeks were 159, 79, 75, and 82 μg/dL, respectively. Blood ammonia concentrations 12 week, 24 weeks, and 48 weeks after L-carnitine administration were significantly lower than those at the start (P < 0.0001, respectively). During the 3 years prior to oral L-carnitine administration, the enrolled patients were hospitalized a total of 29 times for hepatic encephalopathy. However, during the 3 years following oral L-carnitine administration, they were admitted a total of six times for hepatic encephalopathy (P < 0.001). Median survival time was 40.9 months. Child-Pugh scores before and after oral L-carnitine administration differed significantly, whereas liver reserve function, nutritional status, and muscle index did not change significantly.

CONCLUSIONS

Oral L-carnitine administration is effective and free of adverse effects in patients with hyperammonemia and reduces the number of hospital admissions for hepatic encephalopathy.

Association between serum albumin and cognitive dysfunction in hepatic encephalopathy: An exploratory data analysis

Background and Aim

Because covert hepatic encephalopathy (CHE) has been shown to affect the prognosis of cirrhotic patients, early diagnosis of hepatic encephalopathy (HE) is a prerequisite for the preservation of patients' quality of life and for prophylaxis of overt HE. The aim of this study was to identify a clinical parameter to predict impairment of cognitive function in cirrhotic patients with early‐stage HE.

Methods

We investigated the data from 172 patients with cirrhotic or idiopathic portosystemic shunt (PSS) in phase II/III trials of rifaximin in Japan. Classification and regression trees (CARTs) were constructed to identify clinical profiles related to cognitive dysfunction as indicated by the prolongation of time required for the Number Connection Test (NCT‐B).

Results

CART analysis detected age 65 years as the variable for the initial split, and serum albumin level was selected as the variable for the second split among patients aged ≤65 years. In 27 cirrhotic patients aged ≤65 years without PSS, receiver operating characteristic curve analysis revealed that the optimal albumin level cutoff point was 3.05 g/dL, and the area under the curve was 0.80 for the prolongation of NCT‐B time, which was higher than that of the branched‐chain amino acids‐to‐tyrosine ratio (0.46), the prothrombin time–international normalized ratio (PT‐INR) (0.68), serum ammonia (0.61), and total bilirubin (0.69).

Conclusions

Lower serum albumin level as a clinical biomarker associated with impaired cognitive function may be available as a screening examination for early‐stage HE in cirrhotic patients aged ≤65 years without PSS before undergoing neuropsychological tests.

Interplay of cardiovascular mediators, oxidative stress and inflammation in liver disease and its complications

The liver is a crucial metabolic organ that has a key role in maintaining immune and endocrine homeostasis. Accumulating evidence suggests that chronic liver disease might promote the development of various cardiac disorders (such as arrhythmias and cardiomyopathy) and circulatory complications (including systemic, splanchnic and pulmonary complications), which can eventually culminate in clinical conditions ranging from portal and pulmonary hypertension to pulmonary, cardiac and renal failure, ascites and encephalopathy. Liver diseases can affect cardiovascular function during the early stages of disease progression. The development of cardiovascular diseases in patients with chronic liver failure is associated with increased morbidity and mortality, and cardiovascular complications can in turn affect liver function and liver disease progression. Furthermore, numerous infectious, inflammatory, metabolic and genetic diseases, as well as alcohol abuse can also influence both hepatic and cardiovascular outcomes. In this Review, we highlight how chronic liver diseases and associated cardiovascular effects can influence different organ pathologies. Furthermore, we explore the potential roles of inflammation, oxidative stress, vasoactive mediator imbalance, dysregulated endocannabinoid and autonomic nervous systems and endothelial dysfunction in mediating the complex interplay between the liver and the systemic vasculature that results in the development of the extrahepatic complications of chronic liver disease. The roles of ageing, sex, the gut microbiome and organ transplantation in this complex interplay are also discussed.

An update on the pharmacological management and prevention of cerebral edema: current therapeutic strategies

Introduction: Cerebral edema is a common complication of multiple neurological diseases and is a strong predictor of outcome, especially in traumatic brain injury and large hemispheric infarction.Areas Covered: Traditional and current treatments of cerebral edema include treatment with osmotherapy or decompressive craniectomy at the time of clinical deterioration. The authors discuss preclinical and clinical models of a variety of neurological disease states that have identified receptors, ion transporters, and channels involved in the development of cerebral edema as well as modulation of these receptors with promising agents.Expert opinion: Further study is needed on the safety and efficacy of the agents discussed. IV glibenclamide has shown promise in preclinical and clinical trials of cerebral edema in large hemispheric infarct and traumatic brain injury. Consideration of underlying pathophysiology and pharmacodynamics is vital, as the synergistic use of agents has the potential to drastically mitigate cerebral edema and secondary brain injury thusly transforming our treatment paradigms.

The Role of Intestinal Bacteria and Gut-Brain Axis in Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a neurological disorder that occurs in patients with liver insufficiency. However, its pathogenesis has not been fully elucidated. Pharmacotherapy is the main therapeutic option for HE. It targets the pathogenesis of HE by reducing ammonia levels, improving neurotransmitter signal transduction, and modulating intestinal microbiota. Compared to healthy individuals, the intestinal microbiota of patients with liver disease is significantly different and is associated with the occurrence of HE. Moreover, intestinal microbiota is closely associated with multiple links in the pathogenesis of HE, including the theory of ammonia intoxication, bile acid circulation, GABA-ergic tone hypothesis, and neuroinflammation, which contribute to cognitive and motor disorders in patients. Restoring the homeostasis of intestinal bacteria or providing specific probiotics has significant effects on neurological disorders in HE. Therefore, this review aims at elucidating the potential microbial mechanisms and metabolic effects in the progression of HE through the gut-brain axis and its potential role as a therapeutic target in HE.

Management of late onset urea cycle disorders-a remaining challenge for the intensivist?

Background

Hyperammonemia caused by a disorder of the urea cycle is a rare cause of metabolic encephalopathy that may be underdiagnosed by the adult intensivists because of its rarity. Urea cycle disorders are autosomal recessive diseases except for ornithine transcarbamylase deficiency (OTCD) that is X-linked. Optimal treatment is crucial to improve prognosis.

Main body

We systematically reviewed cases reported in the literature on hyperammonemia in adulthood. We used the US National Library of Medicine Pubmed search engine since 2009. The two main causes are ornithine transcarbamylase deficiency followed by type II citrullinemia. Diagnosis by the intensivist remains very challenging therefore delaying treatment and putting patients at risk of fatal cerebral edema. Treatment consists in adapted nutrition, scavenging agents and dialysis. As adults are more susceptible to hyperammonemia, emergent hemodialysis is mandatory before referral to a reference center if ammonia levels are above 200 µmol/l as the risk of cerebral edema is then above 55%. Definitive therapy in urea cycle abnormalities is liver transplantation.

Conclusion

Awareness of urea cycle disorders in adults intensive care units can optimize early management and accordingly dramatically improve prognosis. By preventing hyperammonemia to induce brain edema and herniation leading to death.

Challenges of Delirium Management in Patients with Traumatic Brain Injury: From Pathophysiology to Clinical Practice

Traumatic brain injury (TBI) can initiate a very complex disease of the central nervous system (CNS), starting with the primary pathology of the inciting trauma and subsequent inflammatory and CNS tissue response. Delirium has long been regarded as an almost inevitable consequence of moderate to severe TBI, but more recently has been recognized as an organ dysfunction syndrome with potentially mitigating interventions. The diagnosis of delirium is independently associated with prolonged hospitalization, increased mortality and worse cognitive outcome across critically ill populations. Investigation of the unique problems and management challenges of TBI patients is needed to reduce the burden of delirium in this population. In this narrative review, possible etiologic mechanisms behind post-traumatic delirium are discussed, including primary injury to structures mediating arousal and attention and secondary injury due to progressive inflammatory destruction of the brain parenchyma. Other potential etiologic contributors include dysregulation of neurotransmission due to intravenous sedatives, seizures, organ failure, sleep cycle disruption or other delirium risk factors. Delirium screening can be accomplished in TBI patients and the presence of delirium portends worse outcomes. There is evidence that multi-component care bundles including an analgesia-prioritized sedation algorithm, regular spontaneous awakening and breathing trials, protocolized delirium assessment, early mobility and family engagement can reduce the burden of ICU delirium. The aim of this review is to summarize the approach to delirium in TBI patients with an emphasis on pathogenesis and management. Emerging CNS-active drug therapies that show promise in preclinical studies are highlighted.

Alkalemia and Hepatic Encephalopathy in a Chronic Dialysis Patient

Hepatic encephalopathy (HE) includes cognitive, psychiatric and neuromotor abnormalities observed from brain dysfunction secondary to liver disease and/or porto-systemic shunting. HE can have a wide range of clinical manifestations ranging from trivial lack of awareness, decreased attention span, personality changes to confusion, seizures, coma, and death. The onset of HE in cirrhosis is a poor prognostic factor. While HE has a complex pathogenesis which is not completely understood, hyperammonemia plays an important role in neurotoxicity and brain dysfunction. Alkalemia facilitates the conversion of NH₄⁺ to NH₃, which is free to cross the blood-brain barrier exacerbating HE. Prompt recognition and correction of underlying risk factors is central to the management of HE.

Comprehensive gene expression profiling of human astrocytes treated with a hepatic encephalopathy-inducible factor, alpha 1-antichymotripsin

Astrocytes are major glial cells that play a critical role in brain homeostasis. Abnormalities in astrocytic function, such as hepatic encephalopathy (HE) during acute liver failure, can result in brain death following brain edema and the associated astrocyte swelling. Recently, we have identified alpha 1-antichymotripsin (ACT) to be a biomarker candidate for HE. ACT induces astrocyte swelling by upregulating aquaporin 4 (AQP4); however, the causal connection between these proteins is not clear yet. In this study, we utilized a microarray profile to screen the differentially expressed genes (DEGs) in astrocytes treated with ACT. We then performed Gene Ontology, REACTOME, and the comprehensive resource of mammalian protein complexes (CORUM) enrichment analyses of the identified DEGs. The results of these analyses indicated that the DEGs were enriched in pathways activating adenylate cyclase (AC)-coupled G protein-coupled receptors (GPCRs) and therefore were involved in the cyclic adenosine monophosphate (cAMP) signaling. These results indicate that ACT may act as a ligand of Gs-GPCRs and subsequently upregulate cAMP. As cAMP is known to upregulate AQP4 in astrocytes, these results suggest that ACT may upregulate AQP4 by activating AC GPCRs and therefore serve as a therapeutic target for acute HE.

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The expression of AQP4 is induced by alpha 1-antichymotripsin dependent activation of adenylate cyclase.

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Combination treatment of alpha 1-antichymotripsin and arginine vasopressin enhance the activation of adenylate cyclase.

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Alpha 1-antichemotripsin might be a therapeutic target for acute hepatic encephalopathy.

Liver failure in pregnancy: a review of 25 cases

We retrospectively reviewed the medical records from 25 pregnant women with liver failure from May 2009 to July 2019. Data describing clinical symptoms and manifestations, routine blood analyses, coagulation, and liver and kidney function were extracted. Swansea criteria were assessed to identify variables with prognostic significance for maternal mortality. The results showed that acute fatty liver was the primary cause of liver failure and 8 (88.89%) patients died within 7 days. Swansea diagnostic criteria for assessing the severity of liver failure were consistent with Chinese guidelines and were more systematic and convenient. The incidence of postpartum haemorrhage was 76%, and the velocity of bleeding was approximately 600 mL per hour. Increased Swansea score, hepatic encephalopathy and decreased PWR were important prognostic indicators for mortality. Recovery during the 7 days postpartum period was an important determinant of maternal outcomes.Impact statementWhat is already known on this subject? Liver failure in pregnant women is a rare but potentially devastating disease with a high rate of short-term morbidity and mortality. There are limited reports about clinical predictors of maternal-foetal outcomes and the dilemmas faced in the term of delivery.What the results of this study add? The incidence of postpartum haemorrhage was 76% in pregnant women with liver failure, but the velocity of bleeding was approximately 600 mL per hour. Our study revealed the Swansea score and the ratio of hepatic encephalopathy were significantly higher and platelet-to-white blood cell ratio (PWR) was lower in women who died compared to those who survived. During treatment period, 8 (88.89%) patients died within 7 days.What the implications are of these findings for clinical practice and/or further research? Swansea score, hepatic encephalopathy and PWR were important prognostic indicators for mortality in pregnant women with liver failure. Recovery during the 7 days postpartum period was an important determinant of maternal outcomes. Our findings may prompt researchers to conduct a large multicentre study to evaluate the prognostic indicators for mortality in pregnant women with liver failure.

Hepatic encephalopathy increases the risk of hip fracture: a nationwide cohort study

BACKGROUND

Osteoporotic hip fracture is a common general health problem with a significant impact on human life because it debilitates the patients and largely decreases their quality of life. Early prevention of fractures has become essential in recent decades. This can be achieved by evaluating the related risk factors, as a reference for further intervention. This is especially useful for the vulnerable patient group with comorbidities. Hepatic encephalopathy (HE), a major complication of liver cirrhosis, may increase the rate of falls and weaken the bone. This study evaluated the correlation between hepatic encephalopathy and osteoporotic hip fracture in the aged population using a national database.

METHODS

This retrospective cohort study used data from Taiwan's National Health Insurance Research Database between 2000 and 2012. We included people who were older than 50 years with hepatic encephalopathy or other common chronic illnesses. Patients with and without hepatic encephalopathy were matched at a ratio of 1:4 for age, sex, and index year. The incidence and hazard ratios of osteoporotic hip fracture between the both cohorts were calculated using Cox proportional hazard regression models.

RESULTS

The mean age of the enrolled patients was 66.5 years. The incidence ratio of osteoporotic hip fracture in the HE group was significantly higher than that in the non-HE group (68/2496 [2.7%] vs 98/9984 [0.98%]). Patients with HE were 2.15-times more likely to develop osteoporotic hip fractures than patients without HE in the whole group. The risk ratio was also significantly higher in female and older individuals. The results were also similar in the comorbidity subgroups of hypertension, diabetes mellitus, hyperlipidemia, senile cataract, gastric ulcer, and depression. Alcohol-related illnesses seemed to not confound the results of this study.

CONCLUSIONS

HE is significantly associated with an increased risk of osteoporotic hip fractures, and the significance is not affected by the comorbidities in people aged more than 50 years. The cumulative risk of fracture increases with age.

Shunt-Induced Hepatic Encephalopathy in TIPS: Current Approaches and Clinical Challenges

Transjugular intrahepatic portosystemic shunt (TIPS) is an established treatment tool in decompensated liver cirrhosis that has been shown to prolong transplant-free survival. Hepatic encephalopathy (HE) is a frequent complication of decompensated cirrhosis, eventually induced and/or aggravated by TIPS, that remains a clinical challenge especially in these patients. Therefore, patient selection for TIPS requires careful assessment of risk factors for HE. TIPS procedural parameters regarding stent size and invasive portosystemic pressure gradient measurements thereby have an important role. Endovascular shunt modification, in combination with a conservative medical approach, often results in a significant reduction of symptoms. This review summarizes HE molecular mechanisms and pathophysiology as well as diagnostic and therapeutic approaches targeting shunt-induced HE.

Pharmacological management of portal hypertension and its complications in children: lessons from adults and opportunities for the future

INTRODUCTION

Portal hypertension (PHT) and its complications in children are thought to be distinct from adult PHT in several areas, including the underlying bio-physiology of a child in which PHT develops, but also because of the pediatric-specific etiologies that drive disease progression. And yet pharmacologic approaches to PHT in children are mainly based on adult data, modified for pediatric practice. This reality has been driven by a lack of data specific to children.

AREAS COVERED

The authors discuss current therapeutic approaches to PHT in children, including management of acute gastrointestinal variceal bleed, pharmacotherapy in prophylaxis, and established and emerging therapies to combat systemic co-morbidities that result from PHT. The few areas where pediatric-specific data exist are highlighted and the many gaps in knowledge that remain unresolved are underscored.

EXPERT OPINION

Despite decades of experience, optimal management of pediatric PHT remains undefined. In large part, this can be directly linked to a lack of basic understanding related to the unique pathophysiology and natural history that defines PHT in children. As a result, meaningful research into the utility and effectiveness of pharmacotherapy in children with PHT remains in its infancy. Large, multi-center, prospective studies will be needed to begin to establish an infrastructure on which a pediatric-specific research agenda can be built.

Fibrosis and the intestinal microbiome; a focus on chronic liver disease

The role of the microbiome in progression of liver disease is an exciting area of research that is advancing rapidly supported by the development of next-generation sequencing and bioinformatics tools that simultaneously identify the composition and function of the microbiome. Changes in the microbiome are associated with pathogenesis of chronic liver disease; specifically, changes in microbiome composition predict disease severity and specific microbial signatures can be used to distinguish between mild disease, advanced fibrosis and cirrhosis. Future work combining functional metagenomic analysis with preclinical mechanistic studies will be key to advancing our understanding of how the microbiome affects the pathogenesis of different chronic liver disease aetiologies and to identify personalised therapeutics based on modulation of the microbiome and its function.

Embolization of a paraumbilical shunt by the transparaumbilical venous approach and one-sheath inverse method: A case report

We describe treatment of a 53-year-old man with chronic hepatic encephalopathy. Contrast-enhanced computed tomography demonstrated a recanalized paraumbilical vein as a portosystemic shunt connecting the left branch of the portal vein and bilateral iliac veins. Percutaneous embolization was performed. The paraumbilical vein was punctured under ultrasonographic guidance; a 7-Fr sheath was inserted in the cranial direction. The hepatic side of the shunt was embolized with a vascular plug. The sheath direction was inverted to the caudal side; the pelvic side of the shunt was then embolized with another vascular plug. This report demonstrates that the percutaneous transparaumbilical venous approach is useful and safe for portosystemic shunt intervention. Moreover, the one-sheath inverse method was useful for embolization of upstream and downstream sides of the puncture site.

Direct antivirals and cognitive impairment in hepatitis C: a clinical-neurophysiologic study

Cognition was assessed in hepatitis C virus (HCV) patients, who did not meet the criteria for a minimal hepatic encephalopathy. Their liver function was compensated. We then disentangled potential cognitive changes associated with a sustained virologic response at 12 weeks (SVR-12), following treatment with direct antiviral agents (DAAs). We studied 23 selected HCV patients with a battery of standard neuropsychological tests, and with recordings of the P300 wave, a cerebral potential of “cognitive” significance. There was a baseline evaluation (T0) and a second one 6 months later (T1). We had 2 control groups of comparable age and sex, i.e., 15 patients suffering from non-alcoholic fatty liver disease (NAFLD) and 15 healthy subjects. At T0, we detected a significant (p < 0.05) cognitive impairment in the HCV group, which involved episodic and working memory, attention, visuospatial and verbal abilities, executive functions, and logic reasoning. The P300 latency was significantly (p < 0.05) delayed in the group. At T1, we observed some significant (p < 0.05) HCV recovery in given test domains, e.g., memory, executive functions, and reasoning. Accordingly, the P300 latency shortened significantly (p < 0.05). HCV patients exhibited subtle cognitive defects, somehow independent of their liver condition, possibly linked to direct or indirect brain involvement by the virus. These defects partly recovered following the SVR-12, as achieved through DAAs. The P300 wave was a valid neurophysiologic counterpart of these changes. DAAs can have a role in the early preservation of cognition in HCVs.

Cirrhosis: A Questioned Risk Factor for Hepatocellular Carcinoma

The liver is one of the major metabolic organs in the body, susceptible to injury caused by various factors. In response to injury, sophisticated mechanisms are engaged to repair and regenerate the damaged liver, preventing its failure. When the damage is chronic, regeneration goes awry, impairing liver function and causing cirrhosis. Hence, cirrhosis may rather be a protective response to injury, where wound-healing processes are set to primarily repair the damaged liver. Although cirrhosis is clinically considered a risk factor for hepatocellular carcinoma (HCC), comprehensive population-based studies demonstrate a very modest incidence, refuting the idea that cirrhosis progresses to HCC. Here, we discuss and shed light on the provocative question of whether cirrhosis predisposes to HCC.