Assessment of Cirrhotic Patients by the EncephalApp Fails to Predict Low-Grade Hepatic Encephalopathy.

INTRODUCTION: An early detection of low-grade Hepatic Encephalopathy (HE) is of high importance. The aim of the study was to compare a neuropsychological with a psychophysical test on the basis of the Psychometric Hepatic Encephalopathy Score (PHES) regarding effectiveness in diagnosing minimal HE (MHE). METHODS: In our prospective controlled observational study, we examined a total of 103 patients with liver cirrhosis for HE. The PHES, CFF and EncephalApp were performed in all patients. Graduation was based on the result of the PHES. Patients without evidence for HE 1&2 according to the mental state (West-Haven criteria) with a PHES < -4 value points and no clinical symptoms were defined as having MHE. Patients were considered as HE 0 when in the PHES none of the psychometric subtest results was abnormal or with a PHES  -4 value points. Patients with clinical symptoms were considered HE 1&2 patients. Different Cut-Off values were determined and their specificity and sensitivity calculated. RESULTS: Ninety-six of the involved patients had liver cirrhosis and 25 acted as a healthy control group. The ROC analysis for the classification resulted in an AUC of .806, with the highest Youden index for the Cut-Off time > 224 seconds, for which the sensitivity was 82% and the specificity 75%. Cases of withdrawals were seen in 10.74% of all tested patients. Discussion/ Conclusion: The EncephalApp distinguishes well between HE0 and MHE but has its limitations in grading higher forms of HE. Diagnosis using only the EncephalApp is not sufficient.

[Prognostic significance and economic burden of hepatic encephalopathy in liver cirrhosis in German hospitals based on G-DRG data]. / Mortalität und ökonomische Auswirkungen der hepatischen Enzephalopathie bei Leberzirrhose in deutschen Krankenhäusern auf der Basis von G-DRG-Kostendaten.

INTRODUCTION: Hepatic encephalopathy (HE) represents a frequent complication of liver cirrhosis with negative effects on patients' lives. The prevalence of clinical HE is estimated to be between 30-45 %. Regardless of its clinical and prognostic relevance HE is considered to be underdiagnosed. METHODS: Beyond a systematic analysis of mortality of HE, we investigated the economic impact and reimbursement situation for HE in patients with liver cirrhosis in Germany. For the retrospective analysis, anonymized data (2011-2015) concerning expenses and diagnoses (§â€Š21-4 KHEntgG) were obtained from 74 participating hospitals of the Diagnosis Related Groups (DRG) Project of the German Gastroenterological Association (DGVS). Furthermore, results were compared with case data from all German hospitals provided by the German Federal Authority on Statistics (Statistische Bundesamt (Destatis), Wiesbaden). RESULTS: In participating hospitals 59 093 cases with liver cirrhosis were identified of which 14.6 % were coded as having HE. Hospital mortality was threefold increased compared to cirrhosis-patients without HE (20.9 versus 7.5 %). Cases with cirrhosis as well as the proportion with HE increased over time. Compared to all patients with cirrhosis, reimbursement for HE patients produced a deficit (of up to 634 € for HE grade 4). DISCUSSION: Mortality is threefold increased in patients with cirrhosis when an additional HE is diagnosed. Hospitals participating in the DGVS-DRG-project coded 2 % more HE cases among their cirrhosis cases than the rest of hospitals either because of a selection bias for greater disease severity or because of better coding quality. At present, reimbursement for HE patients on the basis of F-DRG-system produced a deficit.

Ammonia-weighted imaging by chemical exchange saturation transfer MRI at 3 T.

Hepatic encephalopathy (HE) is triggered by liver cirrhosis and is associated with an increased ammonia level within the brain tissue. The goal of this study was to investigate effects of ammonia on in vitro amide proton transfer (APT)-weighted chemical exchange saturation transfer (CEST) imaging in order to develop an ammonia-sensitive brain imaging method. APT-weighted CEST imaging was performed on phantom solutions including pure ammonia, bovine serum albumin (BSA), and tissue homogenate samples doped with various ammonia concentrations. All CEST data were assessed by magnetization transfer ratio asymmetry. In addition, optical methods were used to determine possible structural changes of the proteins in the BSA phantom. In vivo feasibility measurements were acquired in one healthy participant and two patients suffering from HE, a disease associated with increased brain ammonia levels. The CEST effect of pure ammonia showed a base-catalyzed behavior. At pH values greater than 5.6 no CEST effect was observed. The APT-weighted signal was significantly reduced for ammonia concentrations of 5mM or more at fixed pH values within the different protein phantom solutions. The optical methods revealed no protein aggregation or denaturation for ammonia concentrations less than 5mM. The in vivo measurements showed tissue specific and global reduction of the observed CEST signal in patients with HE, possibly linked to pathologically increased ammonia levels. APT-weighted CEST imaging is sensitive to changes in ammonia concentrations. Thus, it seems useful for the investigation of pathologies with altered tissue ammonia concentrations such as HE. However, the underlying mechanism needs to be explored in more detail in future in vitro and in vivo investigations.

Screening for non-alcoholic fatty liver disease in children and adolescents with type 1 diabetes mellitus: a cross-sectional analysis.

The liver is intensely involved in glucose metabolism and is thereby closely related to diabetes pathophysiology. Adult patients with type 1 diabetes mellitus (DM) are at an increased risk for non-alcoholic fatty liver disease (NAFLD). Here, we studied the prevalence of NAFLD in a cohort of children and adolescents with type 1 DM in a tertiary care paediatric diabetes centre in Germany. We screened 93 children and adolescents with type 1 DM using ultrasound, laboratory investigations, and liver stiffness measurements (Fibroscan® [FS] and acoustic radiation force imaging [ARFI]). Of these, 82 (88.1%) had completely normal results in all examined aspects. Only one patient (1.1%) fulfilled the criteria as potential NAFLD with ALT > twice the upper limit of normal. Ten of the 93 patients (10.8%) showed any mild abnormality in at least one examined category including ALT, conventional ultrasounds and liver stiffness measurements. However, none of these ten fulfilled the NAFLD case definition criteria. Therefore, these slightly abnormal results were judged to be unspecific or at least of unknown significance in terms of NAFLD indication. CONCLUSION: Compared to data from the general population, our results do not indicate a significantly increased prevalence of NAFLD in this cohort, and advocate against the systematic screening for NAFLD in paediatric type 1 DM. What is Known: • Non-alcoholic fatty liver disease (NAFLD) is common in adults with type 1 DM, and paediatric patients with type 1 DM in Egypt and Saudi Arabia. What is New: • Our results do not indicate a significantly increased prevalence of NAFLD in a cohort of children and adolescents with type 1 DM from Germany compared to prevalence data from the general population. • This finding advocates against the systematic screening for NAFLD in paediatric type 1 DM in western countries.

Current state of knowledge of hepatic encephalopathy (Part V): clinical efficacy of L-ornithine-L-aspartate in the management of HE.

In cirrhotic patients with portosystemic encephalopathy, OA has confirmed its efficacy both in uncontrolled clinical trials and more recently in placebo-controlled double-blind studies in patients with manifest hepatic encephalopathy and hyperammonemia. OA improved performance in Psyhometric Tests as well as mental state gradation. The therapy had little side effects, increasing with higher intravenously administered dosages, and was well tolerated after oral and parenteral administration.

Qualifying and quantifying minimal hepatic encephalopathy.

Minimal hepatic encephalopathy is the term applied to the neuropsychiatric status of patients with cirrhosis who are unimpaired on clinical examination but show alterations in neuropsychological tests exploring psychomotor speed/executive function and/or in neurophysiological variables. There is no gold standard for the diagnosis of this syndrome. As these patients have, by definition, no recognizable clinical features of brain dysfunction, the primary prerequisite for the diagnosis is careful exclusion of clinical symptoms and signs. A large number of psychometric tests/test systems have been evaluated in this patient group. Of these the best known and validated is the Portal Systemic Hepatic Encephalopathy Score (PHES) derived from a test battery of five paper and pencil tests; normative reference data are available in several countries. The electroencephalogram (EEG) has been used to diagnose hepatic encephalopathy since the 1950s but, once popular, the technology is not as accessible now as it once was. The performance characteristics of the EEG are critically dependent on the type of analysis undertaken; spectral analysis has better performance characteristics than visual analysis; evolving analytical techniques may provide better diagnostic information while the advent of portable wireless headsets may facilitate more widespread use. A large number of other diagnostic tools have been validated for the diagnosis of minimal hepatic encephalopathy including Critical Flicker Frequency, the Inhibitory Control Test, the Stroop test, the Scan package and the Continuous Reaction Time; each has its pros and cons; strengths and weaknesses; protagonists and detractors. Recent AASLD/EASL Practice Guidelines suggest that the diagnosis of minimal hepatic encephalopathy should be based on the PHES test together with one of the validated alternative techniques or the EEG. Minimal hepatic encephalopathy has a detrimental effect on the well-being of patients and their care-givers. It responds well to treatment with resolution of test abnormalities and the associated detrimental effects on quality of life, liver-related mortality and morbidity. Patients will only benefit in this way if they can be effectively diagnosed. Corporate efforts and consensus agreements are needed to develop effective diagnostic algorithms.

Ultrasonography of gallbladder abnormalities due to schistosomiasis.

After malaria, schistosomiasis remains the most important tropical parasitic disease in large parts of the world. Schistosomiasis has recently re-emerged in Southern Europe. Intestinal schistosomiasis is caused by most Schistosoma (S.) spp. pathogenic to humans and leads to chronic inflammation and fibrosis of the colon as well as to liver fibrosis. Gallbladder abnormalities usually occur in patients with advanced hepatic portal fibrosis due to Schistosoma mansoni infection. Occasionally, gallbladder abnormalities have been seen also in children and occurring without associated overt liver abnormalities.The specific S. mansoni-induced gallbladder abnormalities detectable by ultrasound include typical hyperechogenic wall thickening with external gallbladder wall protuberances. The luminal wall surface is smooth. The condition is usually clinically silent although some cases of symptomatic cholecystitis have been described. The ultrasonographic Murphy response is negative. Gallbladder contractility is impaired but sludge and calculi occur rarely. Contrary to other trematodes such as liver flukes, S. mansoni does not obstruct the biliary tract. Advanced gallbladder fibrosis is unlikely to reverse after therapy.

Value of critical flicker frequency and psychometric hepatic encephalopathy score in diagnosis of low-grade hepatic encephalopathy.

BACKGROUND & AIMS: Critical flicker frequency (CFF) and psychometric hepatic encephalopathy score (PHES) analyses are widely used to diagnose hepatic encephalopathy (HE), but little is known about their value in the diagnosis of low-grade HE. METHODS: The diagnostic values of CFF and PHES were compared using a computerized test battery and West Haven criteria as reference. We performed CFF analysis on 559 patients with cirrhosis and 261 without (controls). Of these 820 patients, 448 were evaluated using a modified PHES system and 148 were also evaluated using the conventional PHES system. RESULTS: CFF distinguished between patients with overt HE and without minimal or overt HE in the entire study population with 98% sensitivity and 94% specificity and in the subgroup of patients who were evaluated by conventional PHES with 97% sensitivity and 100% specificity. Conventional PHES identified patients with overt HE with 73% sensitivity and 89% specificity. CFF distinguished between patients with and without minimal HE with only 37% sensitivity but 94% specificity (entire study population). In the subgroup of patients evaluated by conventional PHES, CFF distinguished between patients with and without minimal HE with 22% sensitivity and 100% specificity; these values were similar to those for conventional PHES (30% sensitivity and 89% specificity). The modified PHES distinguished between patients with and without minimal HE with 49% sensitivity and 74% specificity. The diagnostic agreement values between CFF and conventional or modified PHES in patients with minimal HE were only 54% or 47%, respectively. CONCLUSIONS: In an analysis of patients with cirrhosis and controls, CFF distinguished between patients with overt HE and without minimal or overt HE. PHES testing produced a statistically significant difference among groups, but there was considerable overlap between controls and patients with overt HE. PHES, CFF, and a combination of PHES and CFF could not reliably distinguish patients with minimal HE from controls or those with overt HE.

Lowered frequency and impaired modulation of gamma band oscillations in a bimodal attention task are associated with reduced critical flicker frequency.

Visual attention is associated with occipital gamma band activity. While gamma band power can be modulated by attention, the frequency of gamma band activity is known to decrease with age. The present study tested the hypothesis that reduced visual attention is associated with a change in induced gamma band activity. To this end, 26 patients with liver cirrhosis and 8 healthy controls were tested. A subset of patients showed symptoms of hepatic encephalopathy (HE), a frequent neuropsychiatric complication in liver disease, which comprises a gradual increase of cognitive dysfunction including attention deficits. All participants completed a behavioral task requiring shifts of attention between simultaneously presented visual and auditory stimuli. Brain activity was recorded using magnetoencephalography (MEG). The individual critical flicker frequency (CFF) was assessed as it is known to reliably reflect the severity of HE. Results showed correlations of behavioral data and HE severity, as indexed by CFF. Individual visual gamma band peak frequencies correlated positively with the CFF (r=0.41). Only participants with normal, but not with pathological CFF values showed a modulation of gamma band power with attention. The present results suggest that CFF and attentional performance are related. Moreover, a tight relation between the CFF and occipital gamma band activity both in frequency and power is shown. Thus, the present study provides evidence that a reduced CFF in HE, a disease associated with attention deficits, is closely linked to a slowing of gamma band activity and impaired modulation of gamma band power in a bimodal attention task.

Hepatic encephalopathy.

Hepatic encephalopathy (HE) is a prognostically relevant neuropsychiatric syndrome that occurs in the course of acute or chronic liver disease. Besides ascites and variceal bleeding, it is the most serious complication of decompensated liver cirrhosis. Ammonia and inflammation are major triggers for the appearance of HE, which in patients with liver cirrhosis involves pathophysiologically low-grade cerebral oedema with oxidative/nitrosative stress, inflammation and disturbances of oscillatory networks in the brain. Severity classification and diagnostic approaches regarding mild forms of HE are still a matter of debate. Current medical treatment predominantly involves lactulose and rifaximin following rigorous treatment of so-called known HE precipitating factors. New treatments based on an improved pathophysiological understanding are emerging.

Locomotor impairment and cerebrocortical oxidative stress in portal vein ligated rats in vivo.

BACKGROUND & AIMS: Oxidative/nitrosative stress plays an important role in the pathogenesis of hepatic encephalopathy and ammonia toxicity. The present study was undertaken in order to investigate the impact of portal vein ligation on cerebrocortical oxidative stress and its relation to locomotor activity. METHODS: Cerebral protein tyrosine nitration, RNA oxidation, locomotor activity, and microglia activation were studied in rats that underwent portal vein ligation (PVL). RESULTS: Two weeks after PVL, increased levels of protein tyrosine nitration and RNA oxidation were found in the brain. PVL rats exhibited hyperammonemia and reduced locomotor behaviour, but displayed no signs of microglia activation or upregulation of the mRNAs for interleukin-1ß and tumor necrosis factor-α. PVL also had no effect on astrocytic glutamate transporter or inducible nitric-oxide synthase expression. Only cerebral Il-6 mRNA levels were increased. Daily administration of indomethacin prevented PVL-induced protein tyrosine nitration, RNA oxidation, Il-6 mRNA increase, and the impairment of locomotor activity, but did not prevent PVL-induced hyperammonemia. CONCLUSIONS: The data suggest that PVL triggers oxidative/nitrosative stress in the brain without activation of microglia and neuroinflammation. Prevention of protein tyrosine nitration and RNA oxidation by indomethacin also prevents the disturbances in locomotor activity pointing to a relevance of oxidative stress in the pathophysiology of HE.

Oxidative stress markers in the brain of patients with cirrhosis and hepatic encephalopathy.

UNLABELLED: Cell culture studies and animal models point to an important role of oxidative/nitrosative stress in the pathogenesis of cerebral ammonia toxicity. However, it is unknown whether oxidative/nitrosative stress in the brain is also characteristic of hepatic encephalopathy (HE) in humans. We therefore analyzed post mortem cortical brain tissue samples from patients with cirrhosis dying with or without HE in comparison with brains from patients without liver disease. Significantly elevated levels of protein tyrosine-nitrated proteins, heat shock protein-27, and 8-hydroxyguanosine as a marker for RNA oxidation were found in the cerebral cortex of HE patients, but not of patients with cirrhosis but without HE. Glutamine synthetase (GS) activity was significantly decreased, whereas GS protein expression was not significantly affected. Protein expression of the glutamate/aspartate cotransporter was up-regulated in HE, whereas protein expression of neuronal and inducible nitric oxide synthases, manganese-dependent and copper/zinc-dependent superoxide dismutase, and glial glutamate transporter-1 were not significantly increased. CONCLUSION: These data indicate that HE in patients with cirrhosis is associated with oxidative/nitrosative stress, protein tyrosine nitration, and RNA oxidation, suggesting a role of oxidative stress in the pathogenesis of HE in patients with cirrhosis.

Altered motor cortical plasticity in patients with hepatic encephalopathy: A paired associative stimulation study.

OBJECTIVE: Hepatic encephalopathy (HE) is a potentially reversible brain dysfunction caused by liver failure. Altered synaptic plasticity is supposed to play a major role in the pathophysiology of HE. Here, we used paired associative stimulation with an inter-stimulus interval of 25 ms (PAS25), a transcranial magnetic stimulation (TMS) protocol, to test synaptic plasticity of the motor cortex in patients with manifest HE. METHODS: 23 HE-patients and 23 healthy controls were enrolled in the study. Motor evoked potential (MEP) amplitudes were assessed as measure for cortical excitability. Time courses of MEP amplitude changes after the PAS25 intervention were compared between both groups. RESULTS: MEP-amplitudes increased after PAS25 in the control group, indicating PAS25-induced synaptic plasticity in healthy controls, as expected. In contrast, MEP-amplitudes within the HE group did not change and were lower than in the control group, indicating no induction of plasticity. CONCLUSIONS: Our study revealed reduced synaptic plasticity of the primary motor cortex in HE. SIGNIFICANCE: Reduced synaptic plasticity in HE provides a link between pathological changes on the molecular level and early clinical symptoms of the disease. This decrease may be caused by disturbances in the glutamatergic neurotransmission due to the known hyperammonemia in HE patients.

Risk of recurrent hepatic encephalopathy in patients with liver cirrhosis: a German registry study.

BACKGROUND AND AIMS: Patients with hepatic encephalopathy (HE) show low quality of life, recurrent hospitalizations and an increased mortality. We aimed to assess the natural course of patients after a recent episode of overt HE and to identify risk factors for HE recurrence in Germany. METHODS: Fifteen sites took part in a prospective, observational study including patients with liver cirrhosis who had been hospitalized for HE within 3 months before recruitment. Clinical data, psychometric hepatic encephalopathy score (PHES) and critical flicker frequency were assessed quarterly for 1 year. Primary endpoint was HE recurrence requiring hospitalization, all-cause-mortality was treated as a competing risk factor. RESULTS: From January 2014 to March 2016, a total of 115 patients were recruited. Overall 14 premature deaths were documented. For 78 subjects follow-up data were available in accordance with the protocol. After a median of 118 days, more than half of the per-protocol cohort was readmitted to hospital due to HE (N = 34) or died (N = 11). The risk for hospitalization was significantly increased in patients who had been recruited by liver transplant centers (P = 0.003), had had frequent HE relapses prior to recruitment (P = <0.0001) or an abnormal PHES result of <-4 (P = 0.044). Abnormal PHES results barely missed level of significance as an independent risk factor for re-hospitalization in a multivariable competing risk model (P = 0.093). CONCLUSION: Patients with a history of HE are at high risk for the development of recurrent overt HE demanding hospitalization. The PHES test may aid in detection, monitoring and risk stratification of recurrent HE.

Hepatic encephalopathy and fitness to drive.

BACKGROUND & AIMS: Low-grade hepatic encephalopathy (HE) may impair fitness to drive. Driving deficits have not yet been characterized, and their relation to psychometric test results is unclear. METHODS: Fifty-one cirrhotic patients and 48 age-matched controls underwent real driving in a multiple sensor and camera-equipped car, laboratory and "in-car" computer psychometry, and driving instructor's assessment. RESULTS: Ten cirrhotic patients had no hepatic encephalopathy (HE0); 27 and 14 patients suffered from minimal HE (mHE) and overt HE grade I (oHE), respectively. During real driving, mHE and oHE patients showed significantly more violations of in-lane keeping, reduced break use, prolonged reaction times, and diminished stress tolerance compared with control or cirrhotic HE0 patients. In a self-evaluation questionnaire, mHE and oHE, but not the HE0, patients strongly overestimated their driving abilities. According to the driving instructor's assessment, 75%, 48%, and 39% of the patients with HE0, mHE, and oHE, respectively, were fit to drive, compared with 87% in the control group. Driving deficits in oHE patients were largely due to cognitive defects and prolonged reaction times, whereas, in mHE patients, mistakes and attention deficits predominated. Computer psychometric test results worsened with HE severity and age, whereas real driving was age independent. In 25 out of 94 patients, discordant results for driving fitness were obtained (driving instructor's assessment vs computer psychometry); in mHE and oHE patients, the concordance rates were only 62% and 64%, respectively. CONCLUSIONS: Despite significant driving deficits, HE patients overestimate their driving abilities. The presence of mHE does not necessarily predict driving unfitness, and computer-based testings cannot reliably predict driving fitness.

Neurotransmitter receptor imbalances in motor cortex and basal ganglia in hepatic encephalopathy.

Hepatic encephalopathy (HE) in chronic liver disease is characterized by neuropsychiatric and motor disturbances and associated with a net increase of inhibitory neurotransmission. Though many studies, mostly carried out in animal models, have linked dysfunctions of single neurotransmitter systems with the pathogenesis of HE, reports concerning neurotransmitter receptor alterations are controversial. Little is known about the situation in humans. We carried out a multireceptor assessment of HE-associated changes in neurotransmitter receptor densities and affinities in human post-mortem brain samples. Dissociation constants and densities of different binding sites for glutamate, GABA, acetylcholine, norepinephrine, serotonin, dopamine and adenosine were determined by in vitro binding assays and quantitative receptor autoradiography in the motor cortex and putamen of HE and control brains. HE cases do not build a homogeneous group, but differ concerning direction and intensity of binding site density divergences from control values. The acetylcholine M2 binding site dissociation constant was significantly higher in HE brains. Nicotinic acetylcholine and adenosine type 1 and 2A densities were significantly down-regulated in the putamen of HE brains. Our data suggest that neurotransmitter alterations are probably not the primary key factor responsible for the neuropsychiatric and motor disturbances associated with HE.

Pharmacokinetic and Pharmacodynamic Properties of L-Ornithine L-Aspartate (LOLA) in Hepatic Encephalopathy.

L-Ornithine L-aspartate (LOLA), a stable salt of L-ornithine and L-aspartate, readily dissociates into its constituent amino acids that are readily absorbed by active transport, distributed, and metabolized. L-ornithine serves as an intermediary in the urea cycle in periportal hepatocytes in the liver and as an activator of carbamoyl phosphate synthetase, and, like L-aspartate, by transamination to glutamate via glutamine synthetase in perivenous hepatocytes as well as by skeletal muscle and brain. By way of these metabolic pathways, both amino acids participate in reactions whereby the ammonia molecule is incorporated into urea and glutamine and it is the nature, cellular, and biological location of these pathways that underpins the application of LOLA as an effective ammonia-lowering strategy widely used for the management and treatment of hepatic encephalopathy. These metabolic pathways were elucidated based upon studies in experimental animals and were confirmed by studies in patients with severe liver diseases. More recent studies suggest that LOLA may have additional direct hepatoprotective properties. Moreover, its use may result in improvements in skeletal muscle function in cirrhosis.

Efficacy of l-Ornithine l-Aspartate for the Treatment of Hepatic Encephalopathy and Hyperammonemia in Cirrhosis: Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND/OBJECTIVES: l-Ornithine l-Aspartate (LOLA) is a mixture of two endogenous amino acids with the capacity to fix ammonia in the form of urea and/or glutamine. Its' efficacy for the treatment of Hepatic Encephalopathy (HE), a known hyperammonemic disorder, remains the subject of debate. This study quantitatively analyzed the efficacy of LOLA in patients with cirrhosis and HE. METHODS: Efficacy was defined as the extent of lowering of blood ammonia and improvement of mental state assessed in clinically overt HE (OHE) by Westhaven criteria or psychometric testing for assessment of Minimal HE (MHE). Appropriate keywords were used for electronic and/or manual searches of databases to identify RCTs for inclusion. Study quality and risk of bias were assessed using the Jadad Composite Scale together with The Cochrane Scoring Tool. Random Effects Models were used to express pooled Risk Ratio (RR) or Mean Difference (MD) with associated 95% Confidence Intervals (CI). RESULTS: 10 RCTs (884 patients) were included. Regression analysis showed no evidence of publication bias or other small study effects. Eight RCTs had low risk of bias by Jadad/Cochrane criteria. Comparison with placebo/no intervention controls revealed that LOLA was significantly more effective for improvement of mental state in all types of HE (RR 1.36 (95% CI 1.10-1.69), p = 0.005), OHE (RR: 1.19, 95% CI of 1.01-1.39, test for overall effect: Z = 2.14, p = 0.03), MHE (RR: 2.15 (1.48-3.14), p < 0.0001) and for lowering of blood ammonia (MD: -17.50 µmol/l (-27.73 to (-7.26)), p = 0.0008). Improvement of mental state was greater in trials with low risk of bias. Heterogeneity was reduced in trials from Europe or with >100 participants. Oral LOLA appeared particularly effective for the treatment of MHE. CONCLUSION: LOLA appears to improve mental state and lower ammonia in patients with HE or MHE. Further studies are required in some subgroups of HE and in the era of HE reclassification.