Improved cognition after rifaximin treatment is associated with changes in intra- and inter-brain network functional connectivity.

BACKGROUND: Rifaximin is a non-reabsorbable antibiotic which acts at gut level, and improves cognition and inflammatory parameters in minimal hepatic encephalopathy (MHE) patients, but not all patients show the same level of response. This study aims to assess brain activity, both within and between brain networks, following rifaximin treatment, considering the differences between response groups as well. METHODS: Twenty-two healthy controls and 53 patients with cirrhosis (22 without and 31 with MHE, diagnosed by Psychometric Hepatic Encephalopathy Score, PHES) performed psychometric, attention and coordination tests, and blood inflammatory parameters were measured. Resting-state functional magnetic resonance imaging (fMRI) acquisitions were performed on controls and MHE patients. Eighteen MHE patients underwent a rifaximin treatment for 6 months, after which all measures were repeated. fMRI images were analysed and changes after treatment were assessed. RESULTS: After rifaximin treatment, 13 patients improved their PHES score (Responder patients) while 5 did not (Non-responder patients). No significant decrease in blood ammonia was observed after rifaximin treatment, but there was a decrease in plasma inflammatory cytokines in responder patients. A global effect of rifaximin was detected on the sensorimotor and fronto-parietal networks. Responder patients showed a relative increase of thalamic network connectivity in comparison to non-responder patients. Before treatment, responder and non-responder patients showed connectivity differences in basal ganglia network. The connection of the sensorimotor and thalamic networks between them and with other networks suffered changes after treatment. These connections between networks mostly decreased after treatment. All changes and differences showed a significant level of correlation with the performance of psychometric tests and the blood levels of inflammatory biomarkers. CONCLUSIONS: There was an improvement of the communication between executive, motor and attention-related brain areas, and their functional independence following rifaximin treatment. Patients who respond also show a less deteriorated connection involved in these functions before treatment. Results suggest that the improved inflammatory state of MHE patients, following rifaximin treatment would favour the observed changes in brain function and enhanced cognitive performance.

Efficacy and safety of biological treatment for inflammatory bowel disease in elderly patients: Results from a GETECCU cohort.

INTRODUCTION: Biological therapies used for the treatment of inflammatory bowel disease (IBD) have shown to be effective and safe, although these results were obtained from studies involving mostly a young population, who are generally included in clinical trials. The aim of our study was to determine the efficacy and safety of the different biological treatments in the elderly population. METHODS: Multicenter study was carried out in the GETECCU group. Patients diagnosed with IBD and aged over 65 years at the time of initiating biological therapy (infliximab, adalimumab, golimumab, ustekinumab or vedolizumab) were retrospectively included. Among the patients included, clinical response was assessed after drug induction (12 weeks of treatment) and at 52 weeks. Patients' colonoscopy data in week 52 were assessment, where available. Regarding complications, development of oncological events during follow-up and infectious processes occurring during biological treatment were collected (excluding bowel infection by cytomegalovirus). RESULTS: A total of 1090 patients were included. After induction, at approximately 12-14 weeks of treatment, 419 patients (39.6%) were in clinical remission, 502 patients (47.4%) had responded without remission and 137 patients (12.9%) had no response. At 52 weeks of treatment 442 patients (57.1%) had achieved clinical remission, 249 patients had responded without remission (32.2%) and 53 patients had no response to the treatment (6.8%). Before 52 weeks, 129 patients (14.8%) had discontinued treatment due to inefficacy, this being significantly higher (p<0.0001) for Golimumab - 9 patients (37.5%) - compared to the other biological treatments analyzed. With respect to tumor development, an oncological event was observed in 74 patients (6.9%): 30 patients (8%) on infliximab, 23 (7.14%) on adalimumab, 3 (11.1%) on golimumab, 10 (6.4%) on ustekinumab, and 8 (3.8%) on vedolizumab. The incidence was significantly lower (p=0.04) for the vedolizumab group compared to other treatments. As regards infections, these occurred in 160 patients during treatment (14.9%), with no differences between the different biologicals used (p=0.61): 61 patients (19.4%) on infliximab, 39 (12.5%) on adalimumab, 5 (17.8%) on golimumab, 22 (14.1%) on ustekinumab, and 34 (16.5%) on vedolizumab. CONCLUSIONS: Biological drug therapies have response rates in elderly patients similar to those described in the general population, Golimumab was the drug that was discontinued most frequently due to inefficacy. In our experience, tumor development was more frequent in patients who used anti-TNF therapies compared to other targets, although its incidence was generally low and that this is in line with younger patients based on previous literature.

Development and validation of the AMMON-OHE model to predict risk of overt hepatic encephalopathy occurrence in outpatients with cirrhosis.

BACKGROUND & AIMS: Neuropsychological and psychophysical tests are recommended to assess the risk of overt hepatic encephalopathy (OHE), but their accuracy is limited. Hyperammonaemia is central in the pathogenesis of OHE, but its predictive utility is unknown. In this study, we aimed to determine the role of neuropsychological or psychophysical tests and ammonia, and to develop a model (AMMON-OHE) to stratify the risk of subsequent OHE development in outpatients with cirrhosis. METHODS: This observational, prospective study included 426 outpatients without previous OHE from three liver units followed for a median of 2.5 years. Psychometric hepatic encephalopathy score (PHES) <-4 or critical flicker frequency (CFF) <39 was considered abnormal. Ammonia was normalized to upper limit of normal (AMM-ULN) at the respective reference laboratory. Multivariable frailty competing risk and random survival forest analyses were performed to predict future OHE and to develop the AMMON-OHE model. External validation was carried out using 267 and 381 patients from two independent units. RESULTS: Significant differences were found in time-to-OHE (log-rank p <0.001) according to PHES or CFF and ammonia, with the highest risk in patients with abnormal PHES plus high AMM-ULN (hazard ratio 4.4; 95% CI 2.4-8.1; p <0.001 compared with normal PHES and AMM-ULN). On multivariable analysis, AMM-ULN but not PHES or CFF was an independent predictor of the development of OHE (hazard ratio 1.4; 95% CI 1.1-1.9; p = 0.015). The AMMON-OHE model (sex, diabetes, albumin, creatinine and AMM-ULN) showed a C-index of 0.844 and 0.728 for the prediction of a first episode of OHE in two external validation cohorts. CONCLUSIONS: In this study, we developed and validated the AMMON-OHE model, comprising readily available clinical and biochemical variables that can be used to identify outpatients at the highest risk of developing a first episode of OHE. IMPACT AND IMPLICATIONS: In this study, we aimed to develop a model to predict which patients with cirrhosis are at risk of developing overt hepatic encephalopathy (OHE). Using data from three units and including 426 outpatients with cirrhosis, we developed the AMMON-OHE model - comprising sex, diabetes, albumin, creatinine and ammonia levels - which demonstrated good predictive ability. The AMMON-OHE model performs better than PHES and CFF to predict the first episode of OHE in outpatients with cirrhosis. This model was validated in 267 and 381 patients from two independent liver units. The AMMON-OHE model is available online for clinical use.

Randomized, controlled clinical trial of the DIALIVE liver dialysis device versus standard of care in patients with acute-on- chronic liver failure.

BACKGROUND & AIMS: Acute-on-chronic liver failure (ACLF) is characterized by severe systemic inflammation, multi-organ failure and high mortality rates. Its treatment is an urgent unmet need. DIALIVE is a novel liver dialysis device that aims to exchange dysfunctional albumin and remove damage- and pathogen-associated molecular patterns. This first-in-man randomized-controlled trial was performed with the primary aim of assessing the safety of DIALIVE in patients with ACLF, with secondary aims of evaluating its clinical effects, device performance and effect on pathophysiologically relevant biomarkers. METHODS: Thirty-two patients with alcohol-related ACLF were included. Patients were treated with DIALIVE for up to 5 days and end points were assessed at Day 10. Safety was assessed in all patients (n = 32). The secondary aims were assessed in a pre-specified subgroup that had at least three treatment sessions with DIALIVE (n = 30). RESULTS: There were no significant differences in 28-day mortality or occurrence of serious adverse events between the groups. Significant reduction in the severity of endotoxemia and improvement in albumin function was observed in the DIALIVE group, which translated into a significant reduction in the CLIF-C (Chronic Liver Failure consortium) organ failure (p = 0.018) and CLIF-C ACLF scores (p = 0.042) at Day 10. Time to resolution of ACLF was significantly faster in DIALIVE group (p = 0.036). Biomarkers of systemic inflammation such as IL-8 (p = 0.006), cell death [cytokeratin-18: M30 (p = 0.005) and M65 (p = 0.029)], endothelial function [asymmetric dimethylarginine (p = 0.002)] and, ligands for Toll-like receptor 4 (p = 0.030) and inflammasome (p = 0.002) improved significantly in the DIALIVE group. CONCLUSIONS: These data indicate that DIALIVE appears to be safe and impacts positively on prognostic scores and pathophysiologically relevant biomarkers in patients with ACLF. Larger, adequately powered studies are warranted to further confirm its safety and efficacy. IMPACT AND IMPLICATIONS: This is the first-in-man clinical trial which tested DIALIVE, a novel liver dialysis device for the treatment of cirrhosis and acute-on-chronic liver failure, a condition associated with severe inflammation, organ failures and a high risk of death. The study met the primary endpoint, confirming the safety of the DIALIVE system. Additionally, DIALIVE reduced inflammation and improved clinical parameters. However, it did not reduce mortality in this small study and further larger clinical trials are required to re-confirm its safety and to evaluate efficacy. CLINICAL TRIAL NUMBER: NCT03065699.

Extracorporeal liver support and liver transplantation for acute-on-chronic liver failure.

Acute-on-chronic liver failure (ACLF) is defined by acute decompensation, organ failure and a high risk of short-term mortality. This condition is characterized by an overwhelming systemic inflammatory response. Despite treating the precipitating event, intensive monitoring and organ support, clinical deterioration can occur with very poor outcomes. During the last decades, several extracorporeal liver support systems have been developed to try to reduce ongoing liver injury and provide an improved environment for the liver to regenerate or as a bridging therapy until liver transplantation. Several clinical trials have been performed to evaluate the clinical efficacy of extracorporeal liver support systems, but no clear impact on survival has been proven. DIALIVE is a novel extracorporeal liver support device that has been built to specifically address the pathophysiological derangements responsible for the development of ACLF by replacing dysfunctional albumin and removing pathogen and damage-associated molecular patterns (PAMPs and DAMPs). In phase II clinical trial, DIALIVE appears to be safe, and it seems to be associated with a faster time to the resolution of ACLF compared with standard medical treatment. Even in patients with severe ACLF, liver transplantation saves lives and there is clear evidence of transplant benefit. Careful selection of patients is required to attain good results from liver transplantation, but many questions remain unanswered. In this review, we describe the current perspectives on the use of extracorporeal liver support and liver transplantation for ACLF patients.

Neurofilament Light Chain Protein in Plasma and Extracellular Vesicles Is Associated with Minimal Hepatic Encephalopathy and Responses to Rifaximin Treatment in Cirrhotic Patients.

Neurofilament light chain protein (NfL) levels reflect neuronal damage in several neurological diseases and have been proposed as a possible biomarker. Plasma extracellular vesicles (EVs) could play an important role as mediators of the inflammatory changes associated with inducing minimal hepatic encephalopathy (MHE) in cirrhotic patients. This study investigated the association of NfL levels in plasma and EVs with the presence of MHE in cirrhotic patients, and with responses to rifaximin treatment. The NfL levels in plasma and EVs were assessed in 71 patients with liver cirrhosis (40 with MHE and 31 without MHE) and 26 controls. A total of 31 patients with MHE received rifaximin treatment. We examined changes in NfL levels in plasma and EVs before and after 6 months of rifaximin treatment. The NfL measures were correlated with cognitive alterations and plasma inflammatory cytokines. MHE patients showed increased plasma levels of NfL, which were reverted after rifaximin treatment in patients who responded to treatment. The NfL content in EVs also showed a reversal pattern in MHE patients treated with rifaximin. In multivariable analyses, NfL levels were independently associated with the presence of MHE. We also showed that patients with high levels of both ammonia and fractalkine had significantly higher NfL levels than patients with low levels of least one of these parameters. Rifaximin treatment in MHE patients showed promising results in improving axonal damage, suggesting that rifaximin may have therapeutic benefits against disease progression in MHE.

Mild Cognitive Impairment Is Associated with Enhanced Activation of Th17 Lymphocytes in Non-Alcoholic Fatty Liver Disease.

Patients with nonalcoholic fatty liver disease (NAFLD) may show mild cognitive impairment (MCI). The mechanisms involved remain unclear. The plasma concentrations of several cytokines and chemokines were measured in 71 NAFLD patients (20 with and 51 without MCI) and 61 controls. Characterization and activation of leukocyte populations and CD4+ sub-populations were carried out and analyzed by flow cytometry. We analyzed the cytokines released from CD4+ cell cultures and the mRNA expression of transcription factors and receptors in peripheral blood mononuclear cells. The appearance of MCI in NAFLD patients was associated with increased activation of CD4+ T lymphocytes, mainly of the Th17 subtype, increased plasma levels of pro-inflammatory and anti-inflammatory cytokines such as IL-17A, IL-23, IL-21, IL-22, IL-6, INF-γ, and IL-13, and higher expression of the CCR2 receptor. Constitutive expression of IL-17 was found in cultures of CD4+ cells from MCI patients, reflecting Th17 activation. High IL-13 plasma levels were predictive of MCI and could reflect a compensatory anti-inflammatory response to the increased expression of pro-inflammatory cytokines. This study identified some specific alterations of the immune system associated with the appearance of neurological alterations in MCI patients with NAFLD that could be the basis to improve and restore cognitive functions and quality of life in these patients.

Biological treatment interruption in inflammatory bowel disease: Motivation and predictive factors.

BACKGROUND: Loss-of-response and adverse events (AE) to biologics have been linked to HLA-DQA1*05 allele. However, the clinical factors or biologic used may influence treatment duration. Our objective was to evaluate the influence of clinical and therapeutic factors, along with HLA, in biological treatment discontinuation. METHODS: A retrospective study of consecutive IBD patients treated with biologics between 2007 and 2011 was performed. Main outcome was treatment discontinuation due to primary non-response (PNR), secondary loss of response (SLR) or AE. HLA-DQA1 genotyping was done in all patients. Regression analyses were used to assess risk factors of treatment discontinuation. RESULTS: One hundred fifty patients (61% male) with 312 biologic treatments were included. 147 (47%) were discontinued with a cumulative probability of 30%, 41% and 56% at 1, 2 and 5 years. The use of infliximab (p=0.006) and articular manifestations (p<0.05) were associated with treatment discontinuation. Considering cause of withdrawal, Ulcerative Colitis (UC) had a higher proportion of PNR (HR=4.99; 95% CI=1.71-14.63; p=0.003), SLR was higher if biologics had been indicated due to disease flare (HR=2.32; 95% CI=1.05-5.09; p=0.037) while AE were greater with infliximab (HR=2.46; 95% CI=1.48-4.08; p<0.001) or spondylitis (HR=2.46; 95% CI=1.78-6.89; p<0.001). According to the biological drug, HLA-DQA1*05 with adalimumab showed more SLR in cases with Crohn's disease (HR=3.49; 95% CI=1.39-8,78; p=0.008) or without concomitant immunomodulator (HR=2.8; 95% CI=1.1-6.93; p=0.026). CONCLUSIONS: HLA-DQ A1*05 was relevant in SLR of IBD patients treated with adalimumab without immunosupression. In patients treated with other biologics, clinical factors were more important for treatment interruption, mainly extensive UC or extraintestinal manifestations and having indicated the biologic for flare.

Plasma ammonia levels predict hospitalisation with liver-related complications and mortality in clinically stable outpatients with cirrhosis.

BACKGROUND & AIMS: Hyperammonaemia is central in the pathogenesis of hepatic encephalopathy. It also has pleiotropic deleterious effects on several organ systems, such as immune function, sarcopenia, energy metabolism and portal hypertension. This study was performed to test the hypothesis that severity of hyperammonaemia is a risk factor for liver-related complications in clinically stable outpatients with cirrhosis. METHODS: We studied 754 clinically stable outpatients with cirrhosis from 3 independent liver units. Baseline ammonia levels were corrected to the upper limit of normal (AMM-ULN) for the reference laboratory. The primary endpoint was hospitalisation with liver-related complications (a composite endpoint of bacterial infection, variceal bleeding, overt hepatic encephalopathy, or new onset or worsening of ascites). Multivariable competing risk frailty analyses using fast unified random forests were performed to predict complications and mortality. External validation was carried out using prospective data from 130 patients with cirrhosis in an independent tertiary liver centre. RESULTS: Overall, 260 (35%) patients were hospitalised with liver-related complications. On multivariable analysis, AMM-ULN was an independent predictor of both liver-related complications (hazard ratio 2.13; 95% CI 1.89-2.40; p <0.001) and mortality (hazard ratio 1.45; 95% CI 1.20-1.76; p <0.001). The AUROC of AMM-ULN was 77.9% for 1-year liver-related complications, which is higher than traditional severity scores. Statistical differences in survival were found between high and low levels of AMM-ULN both for complications and mortality (p <0.001) using 1.4 as the optimal cut-off from the training set. AMM-ULN remained a key variable for the prediction of complications within the random forests model in the derivation cohort and upon external validation. CONCLUSION: Ammonia is an independent predictor of hospitalisation with liver-related complications and mortality in clinically stable outpatients with cirrhosis and performs better than traditional prognostic scores in predicting complications. LAY SUMMARY: We conducted a prospective cohort study evaluating the association of blood ammonia levels with the risk of adverse outcomes in 754 patients with stable cirrhosis across 3 independent liver units. We found that ammonia is a key determinant that helps to predict which patients will be hospitalised, develop liver-related complications and die; this was confirmed in an independent cohort of patients.

Automated Whole-Liver MRI Segmentation to Assess Steatosis and Iron Quantification in Chronic Liver Disease.

Background Standardized manual region of interest (ROI) sampling strategies for hepatic MRI steatosis and iron quantification are time consuming, with variable results. Purpose To evaluate the performance of automatic MRI whole-liver segmentation (WLS) for proton density fat fraction (PDFF) and iron estimation (transverse relaxometry [R2*]) versus manual ROI, with liver biopsy as the reference standard. Materials and Methods This prospective, cross-sectional, multicenter study recruited participants with chronic liver disease who underwent liver biopsy and chemical shift-encoded 3.0-T MRI between January 2017 and January 2021. Biopsy evaluation included histologic grading and digital pathology. MRI liver sampling strategies included manual ROI (two observers) and automatic whole-liver (deep learning algorithm) segmentation for PDFF- and R2*-derived measurements. Agreements between segmentation methods were measured using intraclass correlation coefficients (ICCs), and biases were evaluated using Bland-Altman analyses. Linear regression analyses were performed to determine the correlation between measurements and digital pathology. Results A total of 165 participants were included (mean age ± standard deviation, 55 years ± 12; 96 women; 101 of 165 participants [61%] with nonalcoholic fatty liver disease). Agreements between mean measurements were excellent, with ICCs of 0.98 for both PDFF and R2*. The median bias was 0.5% (interquartile range, -0.4% to 1.2%) for PDFF and 2.7 sec-1 (interquartile range, 0.2-5.3 sec-1) for R2* (P < .001 for both). Margins of error were lower for WLS than ROI-derived parameters (-0.03% for PDFF and -0.3 sec-1 for R2*). ROI and WLS showed similar performance for steatosis (ROI AUC, 0.96; WLS AUC, 0.97; P = .53) and iron overload (ROI AUC, 0.85; WLS AUC, 0.83; P = .09). Correlations with digital pathology were high (P < .001) between the fat ratio and PDFF (ROI r = 0.89; WLS r = 0.90) and moderate (P < .001) between the iron ratio and R2* (ROI r = 0.65; WLS r = 0.64). Conclusion Proton density fat fraction and transverse relaxometry measurements derived from MRI automatic whole-liver segmentation (WLS) were accurate for steatosis and iron grading in chronic liver disease and correlated with digital pathology. Automated WLS estimations were higher, with a lower margin of error than manual region of interest estimations. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Moura Cunha and Fowler in this issue.

Plasma Extracellular Vesicles Play a Role in Immune System Modulation in Minimal Hepatic Encephalopathy.

Minimal hepatic encephalopathy (MHE) is associated with changes in the immune system including an increased pro-inflammatory environment and altered differentiation of CD4+ T lymphocytes. The mechanisms remain unknown. Changes in extracellular vesicle (EV) cargo including proteins and miRNAs could play a main role as mediators of immune system changes associated with MHE. The aim was to assess whether plasma EVs from MHE patients played a role in inducing the pro-inflammatory environment and altered differentiation of CD4+ T lymphocyte subtypes in MHE patients. We characterized the miRNA and protein cargo of plasma EVs from 50 cirrhotic patients (27 without and 23 with MHE) and 24 controls. CD4+ T cells from the controls were cultured with plasma EVs from the three groups of study, and the cytokine release and differentiation to CD4+ T-cell subtypes were assessed. Plasma EVs from MHE patients had altered miRNA and protein contents, and were enriched in inflammatory factors compared to the controls and patients without MHE. EVs from MHE patients modulated the expression of pro-inflammatory IL-17, IL-21, and TNF-α and anti-inflammatory TGF-ß in cultured CD4+ T lymphocytes, and increased the proportion of Th follicular and Treg cells and the activation of Th17 cells. In conclusion, plasma EVs could play an important role in the induction of immune changes observed in MHE.

Risk factors and management strategies associated with non-response to aminosalicylates as a maintenance treatment in ulcerative colitis.

Aminosalicylates (5-ASA) are used as the first-line maintenance treatment in patients with mild-moderate ulcerative colitis (UC). Early identification of patients at high risk for 5-ASA non-response and appropriate therapeutic escalation are essential to avoid disease progression. However, the absence of a standardized definition for treatment success makes this a challenging task. The focus of the current review was to describe the risk factors and management strategies associated with 5-ASA non-response. Rates of 5-ASA failure can vary from 17 % to 75 % according to different success definitions, of which clinical relapse is the most prevalent and studied condition. Younger age and endoscopic activity at diagnosis, extensive colitis, early need for corticosteroids, elevated inflammatory markers and non-adherence are consistent risk factors of 5-ASA failure. Given the effectiveness, safety profile and tolerability of this medication, therapy optimization is critical before treatment escalation. Combined use of systemic and topical therapy at an appropriate dose in a once-daily administration and control of adherence could improve success rates.

Surgical treatment of an intraductal papillary mucinous neoplasm of the biliary tract diagnosed by SpyGlass®.

We present the case of a 76-year-old male with a history of acute cholecystitis who underwent a scheduled laparoscopic cholecystectomy. Chronic cholecystitis with a thickened cystic duct was observed intraoperatively. The anatomic pathology report found high-grade dysplasia that affected the distal edge of the cystic duct. In view of these findings, an endoscopic retrograde cholangiopancreatography (ERCP) was performed with SpyGlass® and an excrescent lesion suggestive of malignancy adjacent to the cystic-common bile duct junction was observed. A resection of the extrahepatic bile duct was performed with lymphadenectomy of the hepatic hilum and hepaticojejunostomy in a subsequent procedure. The definitive pathology report confirmed pancreaticobiliary intraductal papillary mucinous neoplasia with high-grade dysplasia and free margins.

Selective improvement by rifaximin of changes in the immunophenotype in patients who improve minimal hepatic encephalopathy.

BACKGROUND: Minimal hepatic encephalopathy (MHE) in cirrhotic patients is associated with specific changes in parameters of the immune system reflecting a more pro-inflammatory environment than in patients without MHE. The aims of this work were to assess the effects of rifaximin treatment of cirrhotic patients with MHE on: (1) MHE; (2) intermediate (CD14++CD16+) pro-inflammatory monocytes; (3) expression of early activation marker CD69 in T lymphocytes; (4) autoreactive CD4+CD28- T lymphocytes; (5) differentiation of CD4+ T lymphocytes to Th follicular and Th22; (6) serum IgG levels; and (7) levels of some pro-inflammatory cytokines. METHODS: These parameters were measured by immunophenotyping and cytokine profile analysis in 30 controls without liver disease, 30 cirrhotic patients without MHE and 22 patients with MHE. Patients with MHE were treated with rifaximin and the same parameters were measured at 3 and 6 months of treatment. We assessed if changes in these parameters are different in patients who improve MHE (responders) and those who remain in MHE (non-responders). RESULTS: Rifaximin improved MHE in 59% of patients with MHE. In these responder patients rifaximin normalized all alterations in the immune system measured while in non-responders it normalizes only IL-6, CCL20, and differentiation of T lymphocytes to Th22. Non-responder patients do not show increased expression of CD69 before treatment. CONCLUSIONS: Rifaximin normalizes changes in the immune system in patients who improve MHE but not in non-responders. Some alterations before treatment are different in responders and non-responders. Understanding these differences may identify predictors of the response of MHE to rifaximin.