Impaired Gut-Liver-Brain Axis in Patients with Cirrhosis. Sci Rep. 2016;6:26800. [PMID: 27225869 PMCID: PMC4880966 DOI: 10.1038/srep26800]

Gut Microbiota Modulation and Fecal Transplantation: An Overview on Innovative Strategies for Hepatic Encephalopathy Treatment

Hepatic encephalopathy (HE) is a major complication of cirrhosis, which is associated with gut microbial composition and functional alterations. Current treatments largely focus on gut microbiota using lactulose, rifaximin and other agents. However, despite these treatments, patients with HE have a high rate of readmission, morbidity and cognitive impairment. Fecal microbiota transplant (FMT) involves introduction of a donor microbiota into a recipient and is currently mainly used for recurrent C. difficile infection (rCDI). The role of FMT in cirrhosis and HE is evolving. There have been two randomized clinical trials (RCT) and several case reports/series in cirrhosis. Both RCTs were safety-focused phase 1 trials. One involved pre-FMT antibiotics and FMT enema versus standard of care, while the other involved 15 FMT capsules versus placebo without pre-FMT antibiotics. There was evidence of safety in both trials and the FMT group demonstrated reduction in hospitalizations compared to the non-FMT group. Changes in microbial function centered around short-chain fatty acids, bile acids and brain function showed improvement in the FMT groups. Long-term follow-up demonstrated continued safety and reduction in the antibiotic-resistance gene carriage. However, larger trials of FMT in HE are needed that can refine the dose, duration and route of FMT administration.

Chronic Liver Diseases and the Microbiome-Translating Our Knowledge of Gut Microbiota to Management of Chronic Liver Disease

Chronic liver disease is reaching epidemic proportions with the increasing prevalence of obesity, nonalcoholic liver disease, and alcohol overuse worldwide. Most patients are not candidates for liver transplantation even if they have end-stage liver disease. There is growing evidence of a gut microbial basis for many liver diseases, therefore, better diagnostic, prognostic, and therapeutic approaches based on knowledge of gut microbiota are needed. We review the questions that need to be answered to successfully translate our knowledge of the intestinal microbiome and the changes associated with liver disease into practice.

Distinct gut microbial compositional and functional changes associated with impaired inhibitory control in patients with cirrhosis

Most cirrhosis etiologies, such as alcohol, hepatitis C, and obesity, involve behavior that require the loss of inhibitory control. Once cirrhosis develops, patients can also develop cognitive impairment due to minimal hepatic encephalopathy (MHE). Both processes could have distinct imprints on the gut-liver-brain axis. Determine the impact of inhibitory control versus traditional cirrhosis-related cognitive performance on gut microbial composition and function. Outpatients with cirrhosis underwent two tests for MHE: inhibitory control test (MHEICT, computerized associated with response inhibition) and psychometric hepatic encephalopathy score (MHEPHES, paper-pencil HE-specific associated with subcortical impairment) along with stool collection for metagenomics. MHEICT/not, MHEPHES/not, and discordant (positive on one test but negative on the other) were analyzed for demographics, bacterial species, and gut-brain modules (GBM) using multi-variable analyses. Ninety-seven patients [47 (49%) MHEPHES, 76 (78%) MHEICT, 41 discordant] were enrolled. MHEPHES/not: Cirrhosis severity was worse in MHEPHES without differences in alpha/beta diversity on bacterial species or GBMs. Pathobionts (Enterobacteriaceae) and γ-amino-butryic acid (GABA) synthesis GBM were higher in MHEPHES. MHEICT/not: We found similar cirrhosis severity and metagenomic alpha/beta diversity in MHEICT versus not. However, alpha/beta diversity of GBMs were different in MHEICT versus No-MHE patients. Alistipes ihumii, Prevotella copri, and Eubacterium spp. were higher, while Enterococcus spp. were uniquely lower in MHEICT versus no-MHE and discordant comparisons. GBMs belonging to tryptophan, menaquinone, GABA, glutamate, and short-chain fatty acid synthesis were also unique to MHEICT. Gut microbial signature of impaired inhibitory control, which is associated with addictive disorders that can lead to cirrhosis, is distinct from cirrhosis-related cognitive impairment.

Polysaccharide from Ganoderma lucidum ameliorates cognitive impairment by regulating the inflammation of the brain-liver axis in rats

Ganoderma lucidum (G. lucidum) polysaccharide-1 (GLP-1) is one of the polysaccharides isolated from the fruiting bodies of G. lucidum. Inflammation in the brain-liver axis plays a vital role in the progress of cognitive impairment. In this study, the beneficial effect of GLP-1 on d-galactose (d-gal) rats was carried out by regulating the inflammation of the brain-liver axis. A Morris water maze test was used to assess the cognitive ability of d-gal rats. ELISA and/or western blot analysis were used to detect the blood ammonia and inflammatory cytokines levels in the brain-liver axis. Metabolomic analysis was used to evaluate the changes of small molecule metabolomics between the brain and liver. As a result, GLP-1 could obviously ameliorate the cognitive impairment of d-gal rats. The mechanism was related to the decreasing levels of TNF-α, IL-6, phospho-p38MAPK, phospho-p53, and phospho-JNK1 + JNK2 + JNK3, the increasing levels of IL-10 and TGF-β1, and the regulation of the metabolic disorders of the brain-liver axis. Our study suggests that G. lucidum could be exploited as an effective food or health care product to prevent and delay cognitive impairment and improve the quality of life.

Alternation of supragingival microbiome in patients with cirrhosis of different Child-Pugh scores

OBJECTIVES

The aim of this study was to analyze the differences in the taxonomy and functions of oral microbiome between patients with and without cirrhosis.

MATERIALS AND METHODS

In this study, V4-16S rDNA amplicon sequencing was used to compare the difference of supragingival microbiome in 42 patients and 12 healthy individuals.

RESULTS

Overall, 3,223,529 clean reads were generated, with an average of 59,694 ± 1,548 clean reads per sample. A total of 30 phyla, 78 classes, 116 orders, 167 families, 228 genera, and 114 species were detected in the 54 samples. The differences were detected among groups at each taxonomical level. Functional prediction showed that patients with cirrhosis had a significant higher proportion of the genes associated with carbohydrate transport and metabolism, defense mechanisms, infectious diseases, membrane transport, etc. compared with healthy individuals (p < .05).

CONCLUSIONS

In conclusion, significant differences were observed in compositions and predictive functions of the supragingival microbiome between patients with cirrhosis and that in healthy people. These findings will provide a new insight into the understanding of pathogenesis, diagnosis, prognosis, and therapy of cirrhosis.

Premises among SARS-CoV-2, dysbiosis and diarrhea: Walking through the ACE2/mTOR/autophagy route

Recently, a new coronavirus (SARS-CoV-2) was discovered in China. Due to its high level of contagion, it has already reached most countries, quickly becoming a pandemic. Although the most common symptoms are related to breathing problems, SARS-CoV-2 infections also affect the gastrointestinal tract culminating in inflammation and diarrhea. However, the mechanisms related to these enteric manifestations are still not well understood. Evidence shows that the SARS-CoV-2 binds to the angiotensin-converting enzyme receptor 2 (ACE2) in host cells as a viral invasion mechanism and can infect the lungs and the gut. Other viruses have already been linked to intestinal symptoms through binding to ACE2. In turn, this medical hypothesis article conjectures that the ACE2 downregulation caused by the SARS-CoV-2 internalization could lead to decreased activation of the mechanistic target of mTOR with increased autophagy and lead to intestinal dysbiosis, resulting in diarrhea. Besides that, dysbiosis can directly affect the respiratory system through the lungs. Although there are clues to other viruses that modulate the ACE2/gut/lungs axis, including the participation of autophagy and dysbiosis in the development of gastrointestinal symptoms, there is still no evidence of the ACE2/mTOR/autophagy pathway in SARS-CoV-2 infections. Thus, we propose that the new coronavirus causes a change in the intestinal microbiota, which culminates in a diarrheal process through the ACE2/mTOR/autophagy pathway into enterocytes. Our assumption is supported by premises that unregulated intestinal microbiota increases the susceptibility to other diseases and extra-intestinal manifestations, which can even cause remote damage in lungs. These putative connections lead us to suggest and encourage future studies aiming at assessing the aforementioned hypothesis and regulating dysbiosis caused by SARS-CoV-2 infection, in order to confirm the decrease in lung injuries and the improvement in the prognosis of the disease.

Role of gut microbiota via the gut-liver-brain axis in digestive diseases

The gut-brain axis is a bidirectional information interaction system between the central nervous system (CNS) and the gastrointestinal tract, in which gut microbiota plays a key role. The gut microbiota forms a complex network with the enteric nervous system, the autonomic nervous system, and the neuroendocrine and neuroimmunity of the CNS, which is called the microbiota-gut-brain axis. Due to the close anatomical and functional interaction of the gut-liver axis, the microbiota-gut-liver-brain axis has attracted increased attention in recent years. The microbiota-gut-liver-brain axis mediates the occurrence and development of many diseases, and it offers a direction for the research of disease treatment. In this review, we mainly discuss the role of the gut microbiota in the irritable bowel syndrome, inflammatory bowel disease, functional dyspepsia, non-alcoholic fatty liver disease, alcoholic liver disease, cirrhosis and hepatic encephalopathy via the gut-liver-brain axis, and the focus is to clarify the potential mechanisms and treatment of digestive diseases based on the further understanding of the microbiota-gut- liver-brain axis.

Microbiome: Emerging Concepts in Patients with Chronic Liver Disease

The gut microbiome is an exciting new area of research in chronic liver disease. It has shown promise in expanding our understanding of these complicated disease processes and has opened up new treatment modalities. The aim of this review is to increase understanding of the microbiome and explain the collection and analysis process in the context of liver disease. It also looks at our current understanding of the role of the microbiome in the wide spectrum of chronic liver diseases and how it is being used in current therapies and treatments.

Gut-organ axis: a microbial outreach and networking

Human gut microbiota (GM) includes a complex and dynamic population of microorganisms that are crucial for well-being and survival of the organism. It has been reported as diverse and relatively stable with shared core microbiota, including Bacteroidetes and Firmicutes as the major dominants. They are the key regulators of body homeostasis, involving both intestinal and extra-intestinal effects by influencing many physiological functions such as metabolism, maintenance of barrier homeostasis, inflammation and hematopoiesis. Any alteration in GM community structures not only trigger gut disorders but also influence other organs and cause associated diseases. In recent past, the GM has been defined as a 'vital organ' with its involvement with other organs; thus, establishing a link or a bi- or multidirectional communication axis between the organs via neural, endocrine, immune, humoral and metabolic pathways. Alterations in GM have been linked to several diseases known to humans; although the exact interaction mechanism between the gut and the organs is yet to be defined. In this review, the bidirectional relationship between the gut and the vital human organs was envisaged and discussed under several headings. Furthermore, several disease symptoms were also revisited to redefine the communication network between the gut microbes and the associated organs.

Cognition and hospitalizations are linked with salivary and faecal microbiota in cirrhosis cohorts from the USA and Mexico

BACKGROUND & AIMS

Gut microbiota are affected by diet and ethnicity, which impacts cognition and hospitalizations in cirrhosis.

AIM

Study interactions of diet with microbiota and impact on hospitalizations and cognition in American and Mexican cohorts.

METHODS

Controls and age-balanced patients with compensated/decompensated cirrhosis were included and followed for 90-day hospitalizations. A subset underwent minimal hepatic encephalopathy (MHE) testing. Parameters such as dietary, salivary and faecal microbiota (diversity, taxa analysis, cirrhosis dysbiosis ratio CDR:high = good) between/within countries were analysed. Regression analyses for hospitalizations and MHE were performed.

RESULTS

In all, 275 age-balanced subjects (133 US [40 Control, 50 Compensated, 43 Decompensated] and 142 Mexican [41 Control, 49 Compensated, 52 Decompensated]) were enrolled. MELD/cirrhosis severity was comparable. Diet showed lower protein and animal fat intake in all decompensated patients, but this was worse in Mexico. Diversity was lower in stool and saliva in decompensated patients, and worse in Mexican cohorts. Prevotellaceae were lower in decompensated cirrhosis, particularly those with lower animal fat/protein consumption across countries. Hospitalizations were higher in Mexico vs the USA (26% vs 14%, P = .04). On regression, Prevotellaceae, Ruminococcaceae and Lachnospiraceae lowered hospitalization risk independent of MELD and ascites. MHE testing was performed in 120 (60/country and 20/subgroup) subjects and MHE rate was similar. MELD and decompensation increased while CDR and Prevotellaceae decreased the risk of MHE.

CONCLUSIONS

Changes in diet and microbiota, especially related to animal fat and protein intake and Prevotellaceae, are associated with MHE and hospitalizations in Mexican patients with cirrhosis compared to an American cohort. Nutritional counselling to increase protein intake in cirrhosis could help prevent these hospitalizations.

A story of liver and gut microbes: how does the intestinal flora affect liver disease? A review of the literature

Each individual is endowed with a unique gut microbiota (GM) footprint that mediates numerous host-related physiological functions, such as nutrient metabolism, maintenance of the structural integrity of the gut mucosal barrier, immunomodulation, and protection against microbial pathogens. Because of increased scientific interest in the GM, its central role in the pathophysiology of many intestinal and extraintestinal conditions has been recognized. Given the close relationship between the gastrointestinal tract and the liver, many pathological processes have been investigated in the light of a microbial-centered hypothesis of hepatic damage. In this review we introduce to neophytes the vast world of gut microbes, including prevalent bacterial distribution in healthy individuals, how the microbiota is commonly analyzed, and the current knowledge of the role of GM in liver disease pathophysiology. Also, we highlight the potentials and downsides of GM-based therapy.

Pathophysiology of Hepatic Encephalopathy

Hepatic encephalopathy (HE) is one of the major clinical decompensations of cirrhosis, with a high impact on health care resource utilization and cost. For an effective and comprehensive management of HE, the clinicians need to understand the pathophysiologic mechanisms of HE. This review describes the multiorgan processes involved in HE and how several HE precipitants and treatment strategies act on ammonia production, excretion, and neurotoxicity, including the impact of diabetes and use of cannabinoids. The authors also discuss the current and future role of gut microbiome, systemic/central inflammation, and various neurotransmitters for the pathogenesis and treatment of HE.

Microbiota changes and intestinal microbiota transplantation in liver diseases and cirrhosis

Patients with chronic liver disease and cirrhosis demonstrate a global mucosal immune impairment, which is associated with altered gut microbiota composition and functionality. These changes progress along with the advancing degree of cirrhosis and can be linked with hepatic encephalopathy, infections and even prognostication independent of clinical biomarkers. Along with compositional changes, functional alterations to the microbiota, related to short-chain fatty acids, bioenergetics and bile acid metabolism, are also associated with cirrhosis progression and outcomes. Altering the functional and structural profile of the microbiota is partly achieved by medications used in patients with cirrhosis such as rifaximin, lactulose, proton pump inhibitors and other antibiotics. However, the role of faecal or intestinal microbiota transplantation is increasingly being recognised. Herein, we review the challenges, opportunities and road ahead for the appropriate and safe use of intestinal microbiota transplantation in liver disease.

Ammonia Levels Do Not Guide Clinical Management of Patients With Hepatic Encephalopathy Caused by Cirrhosis

INTRODUCTION

Ammonia appears to play a major role in the pathophysiology of hepatic encephalopathy (HE), but its role in guiding management is unclear. We aimed to understand the impact of ammonia levels on inpatient HE management, hypothesizing that patients with elevated ammonia levels would receive more aggressive lactulose therapy than patients with normal ammonia or no ammonia level drawn.

METHODS

We examined patients with cirrhosis older than 18 years admitted for management of HE from 2005 to 2015. We additionally used propensity matching to control for confounding by the severity of underlying disease. Patients with an ammonia level taken at time of HE diagnosis were further separated into those with normal or elevated ammonia levels. The primary endpoint was the total lactulose (mL) amount (or dose) given in the first 48 hours of HE management.

RESULTS

One thousand two hundred two admissions with HE were identified. Ammonia levels were drawn in 551 (46%) patients; 328 patients (60%) had an abnormal ammonia level (>72 μmol/L). There were no significant differences in the Child-Pugh score, MELD, or Charlson Comorbidity Index in those with and without ammonia levels drawn. The average total lactulose dose over 48 hours was 167 and 171 mL in the no ammonia vs ammonia groups, respectively (P = 0.42). The average lactulose dose in patients with an elevated ammonia level was 161 mL, identical to the lactulose dose in patients with a normal ammonia level. There was no correlation between lactulose dose and ammonia level (R = 0.0026).

DISCUSSION

Inpatient management of HE with lactulose was not influenced by either the presence or level of ammonia level, suggesting that ammonia levels do not guide therapy in clinical practice.

Neuroinflammation in Murine Cirrhosis Is Dependent on the Gut Microbiome and Is Attenuated by Fecal Transplant

Cirrhosis and hepatic encephalopathy (HE) is associated with an altered gut-liver-brain axis. Fecal microbial transplant (FMT) after antibiotics improves outcomes in HE, but the impact on brain function is unclear. The aim of this study is to determine the effect of colonization using human donors in germ-free (GF) mice on the gut-liver-brain axis. GF and conventional mice were made cirrhotic using carbon tetrachloride and compared with controls in GF and conventional state. Additional GF mice were colonized with stool from controls (Ctrl-Hum) and patients with cirrhosis (Cirr-Hum). Stools from patients with HE cirrhosis after antibiotics were pooled (pre-FMT). Stools from the same patients 15 days after FMT from a healthy donor were also pooled (post-FMT). Sterile supernatants were created from pre-FMT and post-FMT samples. GF mice were colonized using stools/sterile supernatants. For all mice, frontal cortex, liver, and small/large intestines were collected. Cortical inflammation, synaptic plasticity and gamma-aminobutyric acid (GABA) signaling, and liver inflammation and intestinal 16s ribosomal RNA microbiota sequencing were performed. Conventional cirrhotic mice had higher degrees of neuroinflammation, microglial/glial activation, GABA signaling, and intestinal dysbiosis compared with other groups. Cirr-Hum mice had greater neuroinflammation, microglial/glial activation, and GABA signaling and lower synaptic plasticity compared with Ctrl-Hum mice. This was associated with greater dysbiosis but no change in liver histology. Pre-FMT material colonization was associated with neuroinflammation and microglial activation and dysbiosis, which was reduced significantly with post-FMT samples. Sterile pre-FMT and post-FMT supernatants did not affect brain parameters. Liver inflammation was unaffected. Conclusion: Fecal microbial colonization from patients with cirrhosis results in higher degrees of neuroinflammation and activation of GABAergic and neuronal activation in mice regardless of cirrhosis compared with those from healthy humans. Reduction in neuroinflammation by using samples from post-FMT patients to colonize GF mice shows a direct effect of fecal microbiota independent of active liver inflammation or injury.

Meta-analysis of magnetic resonance spectroscopy in the diagnosis of hepatic encephalopathy

Objective

Various imaging modalities have been used to explore pathogenic mechanisms and stratify the severity of hepatic encephalopathy (HE). The hypothesis of this meta-analysis was that there is a progressive identifiable derangement of imaging measures using magnetic resonance spectroscopy (MRS) related to the severity of the HE.

Methods

Studies with more than 10 cases and HE diagnosis were identified from the electronic databases PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Literatura Latino Americana em Ciências da Saúde (LILACS), and Cochrane Central Register of Controlled Trials (CENTRAL) through July 25, 2018. Participants were stratified into healthy controls and patients with non-HE (NHE) (cirrhosis without HE), minimal HE (MHE), and overt HE (OHE). Analyses were organized by metabolite studied and brain region examined. Statistical meta-analysis was performed using the metafor package in R (v3.4.1). Pooled standardized mean differences between patient groups were calculated using a random effects model.

Results

We identified 31 studies (1,481 patients) that included data for cirrhosis-related HE. We found the parietal region to be the most reliable in differentiating between patients with and without MHE, with standard mean differences of +0.82 (95% confidence interval [CI] +0.49 to +1.15, p < 0.0001, I2 = 37.45%) for glutamine/glutamate, −0.36 (95% CI −0.61 to −0.10, p = 0.007, I2 = 20.00%) for choline, and−0.77 (95% CI −1.19 to −0.34, p = 0.0004, I2 = 67.48%) for myo-inositol. We also found that glutamine/glutamate was the metabolite that reliably correlated with HE grade in all brain regions.

Conclusions

The meta-analysis reveals that MRS changes in glutamine/glutamate, choline, and myo-inositol, particularly in the parietal lobe, correlate with the severity of HE. MRS may be of value in the assessment of HE.

Role of gut microbiota in liver disease

The gut microbiome is the natural intestinal inhabitant that has been recognized recently as a major player in the maintenance of human health and the pathophysiology of many diseases. Those commensals produce metabolites that have various effects on host biological functions. Therefore, alterations in the normal composition or diversity of microbiome have been implicated in various diseases, including liver cirrhosis and nonalcoholic fatty liver disease. Moreover, accumulating evidence suggests that progression of dysbiosis can be associated with worsening of liver disease. Here, we review the possible roles for gut microbiota in the development, progression, and complication of liver disease.

Role of Gut Dysbiosis in Liver Diseases: What Have We Learned So Far?

Accumulating evidence supports that gut dysbiosis may relate to various liver diseases. Alcoholics with high intestinal permeability had a decrease in the abundance of Ruminnococcus. Intestinal dysmotility, increased gastric pH, and altered immune responses in addition to environmental and genetic factors are likely to cause alcohol-associated gut microbial changes. Alcohol-induced dysbiosis may be associated with gut barrier dysfunction, as microbiota and their products modulate barrier function by affecting epithelial pro-inflammatory responses and mucosal repair functions. High levels of plasma endotoxin are detected in alcoholics, in moderate fatty liver to advanced cirrhosis. Decreased abundance of Faecalibacterium prausnitzii, an anti-inflammatory commensal, stimulating IL-10 secretion and inhibiting IL-12 and interferon-γ expression. Proteobacteria, Enterobacteriaceae, and Escherichia were reported to be increased in NAFLD (nonalcoholic fatty liver disease) patients. Increased abundance of fecal Escherichia to elevated blood alcohol levels in these patients and gut microbiota enriched in alcohol-producing bacteria produce more alcohol (alcohol hypothesis). Some undetermined pathological sequences related to gut dysbiosis may facilitate energy-producing and proinflammatory conditions for the progression of NAFLD. A shortage of autochthonous non-pathogenic bacteria and an overgrowth of potentially pathogenic bacteria are common findings in cirrhotic patients. The ratio of the amounts of beneficial autochthonous taxa (Lachnospiraceae + Ruminococaceae + Veillonellaceae + Clostridiales Incertae Sedis XIV) to those of potentially pathogenic taxa (Enterobacteriaceae + Bacteroidaceae) was low in those with early death and organ failure. Cirrhotic patients with decreased microbial diversity before liver transplantation were more likely to develop post-transplant infections and cognitive impairment related to residual dysbiosis. Patients with PSC had marked reduction of bacterial diversity. Enterococcus and Lactobacillus were increased in PSC patients (without liver cirrhosis.) Treatment-naive PBC patients were associated with altered composition and function of gut microbiota, as well as a lower level of diversity. As serum anti-gp210 antibody has been considered as an index of disease progression, relatively lower species richness and lower abundance of Faecalibacterium spp. in gp210-positive patients are interesting. The dysbiosis-induced altered bacterial metabolites such as a hepatocarcinogenesis promotor DCA, together with a leaky gut and bacterial translocation. Gut protective Akkermansia and butyrate-producing genera were decreased, while genera producing-lipopolysaccharide were increased in early hepatocellular carcinoma (HCC) patients.

Posttraumatic stress disorder is associated with altered gut microbiota that modulates cognitive performance in veterans with cirrhosis

Posttraumatic stress disorder (PTSD) is associated with cirrhosis in veterans, and therapeutic results are suboptimal. An altered gut-liver-brain axis exists in cirrhosis due to hepatic encephalopathy (HE), but the added impact of PTSD is unclear. The aim of this study was to define linkages between gut microbiota and cognition in cirrhosis with/without PTSD. Cirrhotic veterans (with/without prior HE) underwent cognitive testing [PHES, inhibitory control test (ICT), and block design test (BDT)], serum lipopolysaccharide-binding protein (LBP) and stool collection for 16S rRNA microbiota composition, and predicted function analysis (PiCRUST). PTSD was diagnosed using DSM-V criteria. Correlation networks between microbiota and cognition were created. Patients with/without PTSD and with/without HE were compared. Ninety-three combat-exposed male veterans [ (58 yr, MELD 11, 34% HE, 31% combat-PTSD (42 no-HE/PTSD, 19 PTSD-only, 22 HE-only, 10 PTSD+HE)] were included. PTSD patients had similar demographics, alcohol history, MELD, but worse ICT/BDT, and higher antidepressant use and LBP levels. Microbial diversity was lower in PTSD (2.1 ± 0.5 vs. 2.5 ± 0.5, P = 0.03) but unaffected by alcohol/antidepressant use. PTSD (P = 0.02) and MELD (P < 0.001) predicted diversity on regression. PTSD patients showed higher pathobionts (Enterococcus and Escherichia/Shigella) and lower autochthonous genera belonging to Lachnospiraceaeae and Ruminococcaceae regardless of HE. Enterococcus was correlated with poor cognition, while the opposite was true for autochthonous taxa regardless of PTSD/HE. Escherichia/Shigella was only linked with poor cognition in PTSD patients. Gut-brain axis-associated microbiota functionality was altered in PTSD. In male cirrhotic veterans, combat-related PTSD is associated with cognitive impairment, lower microbial diversity, higher pathobionts, and lower autochthonous taxa composition and altered gut-brain axis functionality compared with non-PTSD combat-exposed patients. Cognition was differentially linked to gut microbiota, which could represent a new therapeutic target.NEW & NOTEWORTHY Posttraumatic stress disorder (PTSD) in veterans with cirrhosis was associated with poor cognitive performance. This was associated with lower gut microbial diversity in PTSD with higher pathobionts belonging to Enterococcus and Escherichia/Shigella and lower beneficial taxa belonging to Lachnospiraceaeae and Ruminococcaceae, with functional alterations despite accounting for prior hepatic encephalopathy, psychoactive drug use, or model for end-stage liver disease score. Given the suboptimal response to current therapies for PTSD, targeting the gut microbiota could benefit the altered gut-brain axis in these patients.

Can we 'seize' the gut microbiota to treat epilepsy?

The gut-microbiota, the complex intestinal microbial ecosystem essential to health, is an emerging concept in medicine. Several studies demonstrate a microbiota-gut-brain bidirectional connection via neural, endocrine, metabolic and immune pathways. Accordingly, the gut microbiota has a crucial role in modulating intestinal permeability, to alter local/peripheral immune responses and in production of essential metabolites and neurotransmitters. Its alterations may consequently influence all these pathways that contribute to neuronal hyper-excitability and mirrored neuroinflammation in epilepsy and similarly other neurological conditions. Indeed, pre- and clinical studies support the role of the microbiome in pathogenesis, seizure modulation and responses to treatment in epilepsy. Up to now, researchers have focussed attention above all on the brain to develop antiepileptic treatments, but considering the microbiome, could extend our possibilities for developing novel therapies in the future. We provide here a comprehensive overview of the available data on the potential role of gut microbiota in the physiopathology and therapy of epilepsy and the supposed underlying mechanisms.

Use of proton pump inhibitors and the risk of cholangitis: a nationwide cohort study

BACKGROUND

Proton pump inhibitor (PPI) use may alter the gut microbiome and increase the risk of cholangitis. However, the association of PPI use with the risk of incident cholangitis has not been evaluated.

AIM

To evaluate whether PPI use was associated with a higher risk of cholangitis.

METHODS

This cohort study included a nationwide representative sample of the Korean general population followed up for 10 years (1 January 2003 to 31 December 2013). PPI use was identified from treatment claims and considered as a time-varying variable. Incident cholangitis was identified from hospitalisation and out-patient visit claims.

RESULTS

During 4 212 003 person-years of follow-up, 58,863 participants had at least one PPI prescription and 1 834 participants developed cholangitis. The age-, sex-, residential area- and income-adjusted hazard ratio (HR) for incident cholangitis comparing PPI use with non-use was 6.06 (95% CI, 4.64-7.91). The association was essentially unchanged in fully adjusted models (HR 5.75; 95% CI, 4.39-7.54). The risk was highest during PPI treatment and decreased gradually after PPI discontinuation (Ptrend  <.001).

CONCLUSIONS

In this large cohort, PPI use was associated with an increased risk of cholangitis. Physicians prescribing PPIs should consider cholangitis as a potential complication of PPI use.

Advanced Organ-on-a-Chip Devices to Investigate Liver Multi-Organ Communication: Focus on Gut, Microbiota and Brain

The liver is a key organ that can communicate with many other districts of the human body. In the last few decades, much interest has focused on the interaction between the liver and the gut microbiota, with their reciprocal influence on biosynthesis pathways and the integrity the intestinal epithelial barrier. Dysbiosis or liver disorders lead to0 epithelial barrier dysfunction, altering membrane permeability to toxins. Clinical and experimental evidence shows that the permeability hence the delivery of neurotoxins such as LPS, ammonia and salsolinol contribute to neurological disorders. These findings suggested multi-organ communication between the gut microbiota, the liver and the brain. With a view to in vitro modeling this liver-based multi-organ communication, we describe the latest advanced liver-on-a-chip devices and discuss the need for new organ-on-a-chip platforms for in vitro modeling the in vivo multi-organ connection pathways in physiological and pathological situations.

Targeting the Gut Microbiota to Treat Cachexia

Cachexia occurs in many chronic diseases and is associated with increased morbidity and mortality. It is treated by nutritional support but often with limited effectiveness, leading to the search of other therapeutic strategies. The modulation of gut microbiota, whether through pro-, pre-, syn- or antibiotics or fecal transplantation, is attracting ever-growing interest in the field of obesity, but could also be an interesting and innovative alternative for treating cachexia. This article reviews the evidence linking the features of malnutrition, as defined by the Global Leadership Initiative on Malnutrition [low body mass index (BMI), unintentional body weight loss, low muscle mass, low appetite, and systemic inflammation] and the gut microbiota in human adults with cachexia-associated diseases, and shows the limitations of the present research in that field with suggestions for future directions.

The gut microbiota in transplant patients

Solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients are at increased risk for developing infections due to underlying immunosuppression. Antibiotic use, and in HSCT recipients, the use of preparative regimens prior to transplantation can deplete gut commensal bacteria, resulting in intestinal dysbiosis. Emerging evidence in transplant patients, particularly HSCT, suggest that disturbances in gut microbiota populations are associated with a number of adverse outcomes. Here, we review the outcomes of HSCT and SOT recipients with gut microbiota imbalance or dysbiosis, explore the nascent field of gut microbiome therapeutic approaches including fecal microbiota transplantation and the use of precision probiotics in HSCT and SOT recipients.

Lycopene ameliorates systemic inflammation-induced synaptic dysfunction via improving insulin resistance and mitochondrial dysfunction in the liver-brain axis

Systemic inflammation is an important determinant of synaptic dysfunction, but the underlying molecular mechanisms remain elusive. Lycopene (LYC), a major carotenoid present in tomato, is regarded as a nutraceutical that has significant antioxidant and anti-obesity bioactivities. In the current study, we randomly divided 3-month-old C57BL/6J mice into 3 groups: the control, LPS and LPS + LYC groups (LYC, 0.03% w/w, mixed with normal chow) for 5 weeks, and then mice were intraperitoneally injected with LPS (0.25 mg kg-1) for 9 days. Our results demonstrated that LYC supplementation effectively attenuated LPS-elicited neuronal damage and synaptic dysfunction through increasing the expressions of neurotrophic factors and the synaptic proteins SNAP-25 and PSD-95. LYC ameliorated LPS-induced insulin resistance and mitochondrial dysfunction in the mouse brain and liver. LYC alleviated the neuroinflammation and hepatic inflammation. Furthermore, LYC decreased the circulating levels of insulin and proinflammatory mediators LPS, TNF-α, IL-1β and IL-6. In conclusion, these results indicated that the supplementation of LYC might be a nutritional preventive strategy in systemic inflammation-induced synaptic dysfunction.

Crosstalk Between the Gut Microbiota and the Brain: An Update on Neuroimaging Findings

An increasing amount of evidence suggests that bidirectional communication between the gut microbiome and the central nervous system (CNS), which is also known as the microbiota-gut-brain axis, plays a key role in the development and function of the brain. For example, alterations or perturbations of the gut microbiota (GM) are associated with neurodevelopmental, neurodegenerative, and psychiatric disorders and modulation of the microbiota-gut-brain axis by probiotics, pre-biotics, and/or diet induces preventative and therapeutic effects. The current interpretation of the mechanisms underlying this relationship are mainly based on, but not limited to, parallel CNS, endocrine, and immune-related molecular pathways that interact with each other. Although many studies have revealed the peripheral aspects of this axis, there is a paucity of data on how structural and functional changes in the brain correspond with gut microbiotic states in vivo. However, modern neuroimaging techniques and other imaging modalities have been increasingly applied to study the structure, function, and molecular aspects of brain activity in living healthy human and patient populations, which has resulted in an increased understanding of the microbiota-gut-brain axis. The present review focuses on recent studies of healthy individuals and patients with diverse neurological disorders that employed a combination of advanced neuroimaging techniques and gut microbiome analyses. First, the technical information of these imaging modalities will be briefly described and then the included studies will provide primary evidence showing that the human GM profile is significantly associated with brain microstructure, intrinsic activities, and functional connectivity (FC) as well as cognitive function and mood.

Specific Gut and Salivary Microbiota Patterns Are Linked With Different Cognitive Testing Strategies in Minimal Hepatic Encephalopathy

OBJECTIVES

Minimal hepatic encephalopathy (MHE) is epidemic in cirrhosis, but testing strategies often have poor concordance. Altered gut/salivary microbiota occur in cirrhosis and could be related to MHE. Our aim was to determine microbial signatures of individual cognitive tests and define the role of microbiota in the diagnosis of MHE.

METHODS

Outpatients with cirrhosis underwent stool collection and MHE testing with psychometric hepatic encephalopathy score (PHES), inhibitory control test, and EncephalApp Stroop. A subset provided saliva samples. Minimal hepatic encephalopathy diagnosis/concordance between tests was compared. Stool/salivary microbiota were analyzed using 16srRNA sequencing. Microbial profiles were compared between patients with/without MHE on individual tests. Logistic regression was used to evaluate clinical and microbial predictors of MHE diagnosis.

RESULTS

Two hundred forty-seven patients with cirrhosis (123 prior overt HE, MELD 13) underwent stool collection and PHES testing; 175 underwent inhibitory control test and 125 underwent Stroop testing. One hundred twelve patients also provided saliva samples. Depending on the modality, 59%-82% of patients had MHE. Intertest Kappa for MHE was 0.15-0.35. Stool and salivary microbiota profiles with MHE were different from those without MHE. Individual microbiota signatures were associated with MHE in specific modalities. However, the relative abundance of Lactobacillaceae in the stool and saliva samples was higher in MHE, regardless of the modality used, whereas autochthonous Lachnospiraceae were higher in those without MHE, especially on PHES. On logistic regression, stool and salivary Lachnospiraceae genera (Ruminococcus and Clostridium XIVb) were associated with good cognition independent of clinical variables.

DISCUSSION

Specific stool and salivary microbial signatures exist for individual cognitive testing strategies in MHE. The presence of specific taxa associated with good cognitive function regardless of modality could potentially be used to circumvent MHE testing.

Microbiome and Cognitive Impairment: Can Any Diets Influence Learning Processes in a Positive Way?

The aim of this review is to summarize the effect of human intestinal microbiome on cognitive impairments and to focus primarily on the impact of diet and eating habits on learning processes. Better understanding of the microbiome could revolutionize the possibilities of therapy for many diseases. The authors performed a literature review of available studies on the research topic describing the influence of human microbiome and diet on cognitive impairment or learning processes found in the world's acknowledged databases Web of Science, PubMed, Springer, and Scopus. The digestive tube is populated by billions of living microorganisms including viruses, bacteria, protozoa, helminths, and microscopic fungi. In adulthood, under physiological conditions, the intestinal microbiome appears to be relatively steady. However, it is not true that it would not be influenced, both in the positive sense of the word and in the negative one. The basic pillars that maintain a steady microbiome are genetics, lifestyle, diet and eating habits, geography, and age. It is reported that the gastrointestinal tract and the brain communicate with each other through several pathways and one can speak about gut-brain axis. New evidence is published every year about the association of intestinal dysbiosis and neurological/psychiatric diseases. On the other hand, specific diets and eating habits can have a positive effect on a balanced microbiota composition and thus contribute to the enhancement of cognitive functions, which are important for any learning process.

Dietary approach and gut microbiota modulation for chronic hepatic encephalopathy in cirrhosis

Hepatic encephalopathy (HE) is a common and serious neuropsychiatric complication of cirrhosis, acute liver failure, and porto-systemic shunting. HE largely contributes to the morbidity of patients with liver disease, severely affecting the quality of life of both patients and their relatives and being associated with poor prognosis. Its presentation is largely variable, manifesting with a broad spectrum of cognitive abnormalities ranging from subtle cognitive impairment to coma. The pathogenesis of HE is complex and has historically been linked with hyperammonemia. However, in the last years, it has become evident that the interplay of multiple actors, such as intestinal dysbiosis, gut hyperpermeability, and neuroinflammation, is of crucial importance in its genesis. Therefore, HE can be considered a result of a dysregulated gut-liver-brain axis function, where cognitive impairment can be reversed or prevented by the beneficial effects induced by "gut-centric" therapies, such as non-absorbable disaccharides, non-absorbable antibiotics, probiotics, prebiotics, and fecal microbiota transplantation. In this context dietary modifications, by modulating the intestinal milieu, can also provide significant benefit to cirrhotic patients with HE. This review will provide a comprehensive insight into the mechanisms responsible for gut-liver-brain axis dysregulation leading to HE in cirrhosis. Furthermore, it will explore the currently available therapies and the most promising future treatments for the management of patients with HE, with a special focus on the dietary approach.

Predicting Clinical Outcomes of Cirrhosis Patients With Hepatic Encephalopathy From the Fecal Microbiome

BACKGROUND & AIMS

Gut dysbiosis plays a role in hepatic encephalopathy (HE), while its relationship at the acute episode of overt HE (AHE), the disease progression and clinical outcomes remains unclear. We aimed to identify AHE-specific microbiome and its association to patients' outcomes.

METHODS

We profiled fecal microbiome changes for a cohort of 62 patients with cirrhosis and AHE i) before treatment, ii) 2-3 days after medication and iii) 2-3 months after recovery, and three control cohorts i) healthy individuals, patients with ii) compensated or iii) decompensated cirrhosis.

RESULTS

Comparison of the microbiome shift from compensated, decompensated cirrhosis, AHE to recovery revealed the AHE-specific gut-dysbiosis. The gut microbiome diversity was decreased during AHE, further reduced after medication, and only partially reversed during the recovery. The relative abundance of Bacteroidetes phylum in the microbiome decreased, whereas that of Firmicute, Proteobacteria and Actinobacteria increased in patients during AHE compared with those with compensated cirrhosis. A total of 70 operational taxonomic units (OTUs) were significantly different between AHE and decompensated cirrhosis abundances. Of them, the abundance of Veillonella parvula increased the most during AHE via a metagenomics recovery of the genomes. Moreover, the relative abundances of three (Alistipes, Bacteroides, Phascolarctobacterium) and five OTUs (Clostridium-XI, Bacteroides, Bacteroides, Lactobacillus, Clostridium-sedis) at AHE were respectively associated with HE recurrence and overall survival during the subsequent one-year follow-up.

CONCLUSIONS

AHE-specific gut OTUs were identified that may be involved in HE development and able to predict clinical outcomes, providing new strategies for the prevention and treatment of HE recurrence in patients with cirrhosis.

Association between Psychosocial Stress and Fecal Microbiota in Pregnant Women

Maternal prenatal psychosocial stress is associated with altered child emotional and behavioral development. One potential underlying mechanism is that prenatal psychosocial stress affects child outcomes via the mother's, and in turn the child's, intestinal microbiota. This study investigates the first step of this mechanism: the relation between psychosocial stress and fecal microbiota in pregnant mothers. Mothers (N = 70) provided a late pregnancy stool sample and filled in questionnaires on general and pregnancy-specific stress and anxiety. Bacterial DNA was extracted and analysed by Illumina HiSeq sequencing of PCR-amplified 16 S ribosomal RNA gene fragments. Associations between maternal general anxiety and microbial composition were found. No associations between the other measured psychosocial stress variables and the relative abundance of microbial groups were detected. This study shows associations between maternal pregnancy general anxiety and microbial composition, providing first evidence of a mechanism through which psychological symptoms in pregnancy may affect the offspring.

The role of gut microbiota in liver disease development and treatment

Liver cancer is the sixth most common cancer worldwide, and the third most common cause of cancer-related death. Hepatocellular carcinoma (HCC), which accounts for more than 90% of primary liver cancers, is an important public health problem. In addition to cirrhosis caused by hepatitis B viral (HBV) or hepatitis C viral (HCV) infection, non-alcoholic fatty liver disease (NAFLD) is becoming a major risk factor for liver cancer because of the prevalence of obesity. Non-alcoholic steatohepatitis (NASH) will likely become the leading indication for liver transplantation in the future. It is well recognized that gut microbiota is a key environmental factor in the pathogenesis of liver disease and cancer. The interplay between gut microbiota and liver disease has been investigated in animal and clinical studies. In this article, we summarize the roles of gut microbiota in the development of liver disease as well as gut microbiota-targeted therapies.

Effect of Increasing Age on Brain Dysfunction in Cirrhosis

Patients with cirrhosis are growing older, which could have an impact on brain dysfunction beyond hepatic encephalopathy. Our aim was to study the effect of concomitant aging and cirrhosis on brain inflammation and degeneration using human and animal experiments. For the human study, age-matched patients with cirrhosis and controls between 65 and 85 years underwent cognitive testing, quality of life (QOL) assessment, and brain magnetic resonance (MR) spectroscopy and resting state functional MR imaging (rs-fMRI) analysis. Data were compared between groups. For the animal study, young (10-12 weeks) and old (1.5 years) C57BL/6 mice were given either CCl4 gavage to develop cirrhosis or a vehicle control and were followed for 12 weeks. Cortical messenger RNA (mRNA) expression of inflammatory mediators (interleukin [IL]-6, IL-1β, transforming growth factor β [TGF-β], and monocyte chemoattractant protein 1), sirtuin-1, and gamma-aminobutyric acid (GABA)-ergic synaptic plasticity (neuroligin-2 [NLG2], discs large homolog 4 [DLG4], GABA receptor, subunit gamma 1/subunit B1 [GABRG1/B1]) were analyzed and compared between younger/older control and cirrhotic mice. The human study included 46 subjects (23/group). Patients with cirrhosis had worse QOL and cognition. On MR spectroscopy, patients with cirrhosis had worse changes related to ammonia and lower N-acetyl aspartate, whereas rs-fMRI analysis revealed that these patients demonstrated functional connectivity changes in the frontoparietal cortical region compared to controls. Results of the animal study showed that older mice required lower CCl4 to reach cirrhosis. Older mice, especially with cirrhosis, demonstrated higher cortical inflammatory mRNA expression of IL-6, IL-1β, and TGF-β; higher glial and microglial activation; and lower sirtuin-1 expression compared to younger mice. Older mice also had lower expression of DLG4, an excitatory synaptic organizer, and higher NLG2 and GABRG1/B1 receptor expression, indicating a predominantly inhibitory synaptic organization. Conclusion: Aging modulates brain changes in cirrhosis; this can affect QOL, cognition, and brain connectivity. Cortical inflammation, microglial activation, and altered GABA-ergic synaptic plasticity could be contributory.

Altered Microbiome in Patients With Cirrhosis and Complications

In patients with cirrhosis, the gut microbiome are affected by multiple gut and systemic alterations. These changes lead to dysbiosis in the microbiota of different parts of the body, resulting in inflammation. The constant immune stimulation resulting in part from dysbiosis is associated with morbidity in patients with cirrhosis. Dysbiosis as a dynamic event worsens with decompensation such as with hepatic encephalopathy, infections or acute-on-chronic liver failure (ACLF). These microbial patterns could be applied as diagnostic and prognostic measures in cirrhosis in the outpatient and inpatient setting. Current therapies for cirrhosis have differing impacts on gut microbial composition and functionality. Dietary modifications and the oral cavity have emerged as newer targetable factors to modulate the microbiome, which could affect inflammation and, potentially improve outcomes. Additionally, fecal microbial transplant is being increasingly studied to provide compositional and functional modulation of the microbiome. Ultimately, a combination of targeted therapies may be needed to provide an optimal gut milieu to improve outcomes in cirrhosis.

Clinical Application and Potential of Fecal Microbiota Transplantation

Fecal microbiota transplantation (FMT) is a well-established treatment for recurrent Clostridioides difficile infection. FMT has become a more readily available and useful new treatment option as a result of stool banks. The current state of knowledge indicates that dysbiosis of the gut microbiota is implicated in several disorders in addition to C. difficile infection. Randomized controlled studies have shown FMT to be somewhat effective in treating ulcerative colitis, irritable bowel syndrome, and hepatic encephalopathy. In addition, FMT has been beneficial in treating several other conditions, such as the eradication of multidrug-resistant organisms and graft-versus-host disease. We expect that FMT will soon be implemented as a treatment strategy for several new indications, although further studies are needed.

Gut Microbiota's Relationship with Liver Disease and Role in Hepatoprotection by Dietary Natural Products and Probiotics

A variety of dietary natural products have shown hepatoprotective effects. Increasing evidence has also demonstrated that gut microorganisms play an important role in the hepatoprotection contributed by natural products. Gut dysbiosis could increase permeability of the gut barrier, resulting in translocated bacteria and leaked gut-derived products, which can reach the liver through the portal vein and might lead to increased oxidative stress and inflammation, thereby threatening liver health. Targeting gut microbiota modulation represents a promising strategy for hepatoprotection. Many natural products could protect the liver from various injuries or mitigate hepatic disorders by reverting gut dysbiosis, improving intestinal permeability, altering the primary bile acid, and inhibiting hepatic fatty acid accumulation. The mechanisms underlying their beneficial effects also include reducing oxidative stress, suppressing inflammation, attenuating fibrosis, and decreasing apoptosis. This review discusses the hepatoprotective effects of dietary natural products via modulating the gut microbiota, mainly focusing on the mechanisms of action.

Research progress on human microecology and infectious diseases

Human microecology has been extensively investigated. Similar to an important physiologically functioning organ of the human body, the microecological system is one of the leading systems for environmental survival, health, genetics, disease, and aging. It is also an essential carrier for drug metabolism and microbial resistance. The occurrence, development, and deterioration of many infectious diseases are closely related to human microecological systems. This study mainly focuses on the changes in microbial groups associated with various infectious diseases to explore the relevant role of human microecology in the development of infectious diseases and its breakthrough implications in future accurate treatments of infectious diseases.

Clinical impact of microbiome in patients with decompensated cirrhosis

Cirrhosis is an increasing cause of morbidity and mortality. Recent studies are trying to clarify the role of microbiome in clinical exacerbation of patients with decompensated cirrhosis. Nowadays, it is accepted that patients with cirrhosis have altered salivary and enteric microbiome, characterized by the presence of dysbiosis. This altered microbiome along with small bowel bacterial overgrowth, through translocation across the gut, is associated with the development of decompensating complications. Studies have analyzed the correlation of certain bacterial families with the development of hepatic encephalopathy in cirrhotics. In general, stool and saliva dysbiosis with reduction of autochthonous bacteria in patients with cirrhosis incites changes in bacterial defenses and higher risk for bacterial infections, such as spontaneous bacterial peritonitis, and sepsis. Gut microbiome has even been associated with oncogenic pathways and under circumstances might promote the development of hepatocarcinogenesis. Lately, the existence of the oral-gut-liver axis has been related with the development of decompensating events. This link between the liver and the oral cavity could be via the gut through impaired intestinal permeability that allows direct translocation of bacteria from the oral cavity to the systemic circulation. Overall, the contribution of the microbiome to pathogenesis becomes more pronounced with progressive disease and therefore may represent an important therapeutic target in the management of cirrhosis.

Proton Pump Inhibitor Initiation and Withdrawal affects Gut Microbiota and Readmission Risk in Cirrhosis

OBJECTIVES

Cirrhosis is associated with gut microbial dysbiosis, high readmissions and proton pump inhibitor (PPI) overuse, which could be inter-linked. Our aim was to determine the effect of PPI use, initiation and withdrawl on gut microbiota and readmissions in cirrhosis.

METHODS

Four cohorts were enrolled. Readmissions study: Cirrhotic inpatients were followed throughout the hospitalization and 30/90-days post-discharge. PPI initiation, withdrawal/continuation patterns were analyzed between those with/without readmissions. Cross-sectional microbiota study: Cirrhotic outpatients and controls underwent stool microbiota analysis. Beneficial autochthonous and oral-origin taxa analysis vis-à-vis PPI use was performed. Longitudinal studies: Two cohorts of decompensated cirrhotic outpatients were enrolled. Patients on chronic unindicated PPI use were withdrawn for 14 days. Patients not on PPI were started on omeprazole for 14 days. Microbial analysis for oral-origin taxa was performed pre/post-intervention.

RESULTS

Readmissions study: 343 inpatients (151 on admission PPI) were enrolled. 21 were withdrawn and 45 were initiated on PPI resulting in a PPI use increase of 21%. PPIs were associated with higher 30 (p = 0.002) and 90-day readmissions (p = 0.008) independent of comorbidities, medications, MELD and age. Cross-sectional microbiota: 137 cirrhotics (59 on PPI) and 45 controls (17 on PPI) were included. PPI users regardless of cirrhosis had higher oral-origin microbiota while cirrhotics on PPI had lower autochthonous taxa compared to the rest. Longitudinal studies: Fifteen decompensated cirrhotics tolerated omeprazole initiation with an increase in oral-origin microbial taxa compared to baseline. PPIs were withdrawn from an additional 15 outpatients, which resulted in a significant reduction of oral-origin taxa compared to baseline.

CONCLUSIONS

PPIs modulate readmission risk and microbiota composition in cirrhosis, which responds to withdrawal. The systematic withdrawal and judicious use of PPIs is needed from a clinical and microbiological perspective in decompensated cirrhosis.