Exploring the Link between Helicobacter pylori, Gastric Microbiota and Gastric Cancer.

Gastric cancer (GC) still represents one of the leading causes of cancer-related mortality and is a major public health issue worldwide. Understanding the etiopathogenetic mechanisms behind GC development holds immense potential to revolutionize patients' treatment and prognosis. Within the complex web of genetic predispositions and environmental factors, the connection between Helicobacter pylori (H. pylori) and gastric microbiota emerges as a focus of intense research investigation. According to the most recent hypotheses, H. pylori triggers inflammatory responses and molecular alterations in gastric mucosa, while non-Helicobacter microbiota modulates disease progression. In this review, we analyze the current state of the literature on the relationship between H. pylori and non-Helicobacter gastric microbiota in gastric carcinogenesis, highlighting the mechanisms by which microecological dysbiosis can contribute to the malignant transformation of the mucosa.

The professional background of a referring physician predicts the diagnostic yield of small bowel capsule endoscopy in suspected small bowel bleeding.

Background and study aims The diagnostic yield of small-bowel capsule endoscopy (SBCE) in suspected small bowel bleeding (SSBB) is highly variable. Different reimbursement systems and equipment costs also limit SBCE use in clinical practice. Thus, minimizing non-diagnostic procedures is advisable. This study aimed to assess the SBCE diagnostic yield and identify factors predicting diagnostic findings in a cohort of patients with SSBB. Patients and methods In this retrospective cohort study, we analyzed the medical records of patients who consecutively underwent SBCE for SSBB over 9 years. By logistic regression, we identified covariates predicting diagnostic findings at SBCE. Finally, we performed a post-hoc cost analysis based on previous gastroenterologist or endoscopist consultations versus direct SBCE ordering by other specialists. Results The final analysis included 584 patients. Most SBCEs were ordered by a gastroenterologist or endoscopist (74%). The number of SBCEs without any finding was significantly lower in the gastroenterologist/endoscopist group P <0.001). The SBCE diagnostic yield ordered by a gastroenterologist or endoscopist was significantly higher than that by other specialists (63% vs 52%, odds ratio [OR] 1.57; 95% confidence interval [CI] 1.07-2.26, P =0.019). At multivariate analysis, older age (OR 1.7, 95%CI 1.2-2.4, P =0.005), anemia (OR 4.9, 95%CI 1.9-12, P =0.001), small bowel transit time (OR 1, 95%CI 1-1.02, P =0.039), and referring physician (OR 1.8, 95%CI 1.1-2.7, P =0.003) independently predicted diagnostic findings. Implementing prior gastroenterologist or endoscopist referral vs direct SBCE ordering would reduce medical expenditures by 16%. Conclusions The professional background of referring physicians significantly improves the diagnostic yield of SBCE and contributes to controlling public health costs.

Autoimmune liver diseases and SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing coronavirus disease 2019 (COVID-19), can trigger autoimmunity in genetically predisposed individuals through hyperstimulation of immune response and molecular mimicry. Here we summarise the current knowledge about auto-immune liver diseases (AILDs) and SARS-CoV-2, focusing on: (1) The risk of SARS-CoV-2 infection and the course of COVID-19 in patients affected by AILDs; (2) the role of SARS-CoV-2 in inducing liver damage and triggering AILDs; and (3) the ability of vaccines against SARS-CoV-2 to induce autoimmune responses in the liver. Data derived from the literature suggest that patients with AILDs do not carry an increased risk of SARS-Cov-2 infection but may develop a more severe course of COVID-19 if on treatment with steroids or thiopurine. Although SARS-CoV-2 infection can lead to the development of several autoimmune diseases, few reports correlate it to the appearance of de novo manifestation of immune-mediated liver diseases such as autoimmune hepatitis (AIH), primary biliary cholangitis (PBC) or AIH/PBC overlap syndrome. Different case series of an AIH-like syndrome with a good prognosis after SARS-CoV-2 vaccination have been described. Although the causal link between SARS-CoV-2 vaccines and AIH cannot be definitively established, these reports suggest that this association could be more than coincidental.

Probiotics in Gastrointestinal Diseases: All that Glitters Is Not Gold.

BACKGROUND: Multiple lines of evidence now support the notion that gut microbiota can contribute to digestive and extra-digestive diseases. The emergence of these observations enabled to postulate a bacteria-centric paradigm to rethink the treatment of many diseases. The goal of therapy should not be to eradicate the flora but to modify it in a way that leads to symptomatic improvement; thus, the interest in the use of probiotics to modulate microbiota composition has increased worldwide in both community and healthcare settings. SUMMARY: The results of published studies are conflicting for most probiotic strains and formulations, and clinicians and consumers need a better understanding of probiotic risks and benefits. Currently, clear guidelines on when to use probiotics and the most effective probiotic for different gastrointestinal conditions are still lacking. Here, we reviewed the studies on the use of probiotics in some diseases of relevant interest to gastroenterologists, such as Helicobacter pylori infection, irritable bowel syndrome, and inflammatory bowel disease. Key Message: Although the evidence is relevant and promising for probiotics in general, and for specific strains and combinations of strains, it is not yet sufficient to draw unequivocal conclusions and clear recommendations.

Gut Microbes and Hepatic Encephalopathy: From the Old Concepts to New Perspectives.

Hepatic encephalopathy (HE) is a severe complication of advanced liver disease and acute liver failure. The clinical spectrum ranges from minor cognitive dysfunctions to lethargy, depressed consciousness, and coma and significantly impact the quality of life, morbidity, and mortality of the patients. It is commonly accepted that the gut milieu is essential for the development of HE; however, despite intensive research efforts, the pathogenesis of HE is still not fully elucidated. As our knowledge of gut microbiota moves from the pioneering era of culture-dependent studies, the connection between microbes, inflammation, and metabolic pathways in the pathogenesis of HE is becoming increasingly clear, providing exciting therapeutic perspectives. This review will critically examine the latest research findings on the role of gut microbes in the pathophysiological pathways underlying HE. Moreover, currently available therapeutic options and novel treatment strategies are discussed.

Blinded Oral Challenges with Lactose and Placebo Accurately Diagnose Lactose Intolerance: A Real-Life Study.

Lactose intolerance (LI) is characterized by diarrhea, abdominal pain, or bloating occurring after lactose consumption in patients with lactose malabsorption. The National Institute of Health (NIH) proposed a double-blind placebo testing to identify LI individuals correctly. However, until now, no study used this approach in a real-life setting. We aimed to assess double-blind placebo challenge accuracy in diagnosing LI in patients with self-reported symptoms of LI. 148 patients with self-reported LI were consecutively enrolled and blindly underwent hydrogen breath test (HBT) after 25 g lactose or 1 g glucose (placebo) load. One week later, the subjects were challenged with the alternative substrate. Each subject completed a validated questionnaire, including five symptoms (diarrhea, abdominal pain, vomiting, bowel sounds, and bloating) scored on a 10-cm visual analog scale. Home questionnaire (HQ) referred to symptoms associated with the consumption of dairy products at home, while lactose questionnaire (LQ) and placebo questionnaire (PQ) referred to symptoms perceived throughout the 4-h after the administration of the substrates, respectively. After lactose load, HBT was positive in 81 patients (55%), of whom 60 (74%) reported relevant symptoms at LQ (lactose malabsorbers, LM). After placebo challenge, 45 out of 60 with a positive lactose challenge did not complain of symptoms and therefore were diagnosed as lactose intolerant, according to NIH definition. The blinded oral challenges with lactose and placebo accurately diagnose LI and identify patients who will likely benefit from a lactose-free diet.

Impact of proton pump inhibitors on cytochrome P450 activity assessed by 13 C-aminopyrine breath test in patients with cirrhosis.

BACKGROUND: Chronic use of proton pump inhibitors (PPIs) in patients with impaired liver function may worsen cytochrome P450 (CYP450) activity, predisposing them to clinically relevant drug-drug interactions. The 13 C-aminopyrine breath test (13 C-ABT) is a non-invasive tool to study CYP450-dependent liver function. AIMS: To assess 13 C-ABT modifications with different PPIs in patients with cirrhosis METHODS: Sixty consecutive patients with HCV-related cirrhosis and indication to start PPI therapy were randomised to receive omeprazole 20 mg/day, esomeprazole 20 mg/day, lansoprazole 15 mg/day, pantoprazole 40 mg/day or rabeprazole 20 mg/day. 13 C-ABT was performed at baseline and on the 15th day of PPI therapy. RESULTS: At baseline, mean values of max 13 C% dose/h and 13 C% cum dose at 120 minutes did not differ significantly among groups. On the 15th day of therapy, max 13 C% dose/h and 13 C% cum dose at 120 minutes did not significantly differ with respect to baseline for pantoprazole (P = 0.184 and P = 0.309, respectively) or rabeprazole (P = 0.536 and P = 0.286, respectively), but were significantly decreased on omeprazole (P = 0.013 and P = 0.015, respectively), esomeprazole (P = 0.009 and P = 0.001, respectively), and lansoprazole (P = 0.033 and P = 0.035, respectively). CONCLUSIONS: In patients with cirrhosis, omeprazole, esomeprazole and lansoprazole inhibit microsomal activity while pantoprazole and rabeprazole do not have a significant impact. Should our data be confirmed in larger cohort studies, pantoprazole and rabeprazole could be safely recommended for patients with cirrhosis.

Bone Marrow of Contention: A Rare Case of Recurrent Acute Hepatitis.

Hepatitis-associated aplastic anemia is a well-recognized clinical syndrome in which marrow failure follows the development of hepatitis. Although aplastic anemia is intimately related to paroxysmal nocturnal hemoglobinuria, until now, no cases of PNH-associated hepatitis have been described. We report a case of recurrent acute hepatitis preceding the clinical onset of PNH. Treatment of PNH with the complement inhibitor eculizumab (Soliris®) prevented both recurrences of episodes of intravascular hemolysis and liver enzyme alteration. This is the first known published case of PNH-associated hepatitis.

Over-the-scope clip vs epinephrine with clip for first-line hemostasis in non-variceal upper gastrointestinal bleeding: a propensity score match analysis.

Background and study aims The over-the-scope clip (OTSC) is a novel tool used to improve the maintenance of hemostasis for non-variceal upper gastrointestinal bleeding (NVUGIB); however, studies on the comparison with "conventional" techniques are lacking. In this study, we aimed to compare first-line endoscopic hemostasis achieved using conventional techniques with that achieved using OTSC placement for NVUGIB. Patients and methods From January 2007 to March 2018, 793 consecutive patients underwent upper endoscopy with the hemostasis procedure. Among them, 327 patients were eligible for inclusion (112 patients had OTSC placement and 215 underwent conventional hemostasis). After propensity score matching and adjustment for confounding factors, 84 patients were stratified into the "conventional" group and 84 into the OTSC group. Patient characteristics and outcomes (rebleeding rate, mortality rate within 30 days, and adverse events) were compared between the two groups. Results In the unmatched cohort, hemostasis with OTSC was more frequent in cases of duodenal ulcers with Forrest Ia to IIa and in patients with a higher Rockall score compared with the "conventional group". In the matched cohort, 93 % of the patients in the "conventional group" underwent hemostasis with epinephrine + through-the-scope clip. Rebleeding events were significantly less frequent in the OTSC group (8 % vs 20 %, 95 %CI 3 - 16 vs 12 - 30; P  = 0.02); however, the mortality rate in the two groups was not significantly different (6 % vs 2 %, 95 %CI 1 - 8 vs 2 - 13; P  = 0.4). Conclusions OTSC is a safe and effective tool for achieving hemostasis, and we recommend its use as the first-line therapy for lesions with a high risk of rebleeding and in patients with a high risk Rockall score.

Lactobacillus casei DG and its postbiotic reduce the inflammatory mucosal response: an ex-vivo organ culture model of post-infectious irritable bowel syndrome.

BACKGROUND: The evidence on the role of gut microbiota in post-infectious irritable bowel syndrome (PI-IBS) is convincing. Lactobacillus spp. positively affect IBS symptoms, although the mechanisms through which probiotics exert their beneficial effects are largely unknown. The aim of the study is to evaluate the role of Lactobacillus casei DG (LC-DG) and its postbiotic (PB) in modulating the inflammatory/immune-response in PI-IBS in an ex-vivo organ culture model. METHODS: Ex vivo cultures of ileal and colonic mucosa from 10 PI-IBS, diarrhea predominant subtype (D) patients, and 10 healthy controls (HC) were treated with LPS, LC-DG and PB. Interleukin (IL)-1α, IL-6, IL-8 and IL-10 mRNA levels were assessed by real-time PCR and Toll like receptor 4 (TLR-4) protein expression by Western blotting. RESULTS: At baseline, IL-1α, IL-6 and IL-8 mRNA levels as well as TLR-4 protein expression were significantly higher while IL-10 mRNA levels were lower in PI-IBS D than in HC in both ileum and colon. LC-DG and PB significantly reduced the mRNA levels of pro-inflammatory cytokines and TLR-4 while increased that of IL-10 after LPS stimulation. The protective effect was more pronounced for PB than LC-DG treatment. CONCLUSION: LC-DG and its PB attenuate the inflammatory mucosal response in an ex-vivo organ culture model of PI-IBS D.

Lactobacillus paracasei F19 versus placebo for the prevention of proton pump inhibitor-induced bowel symptoms: a randomized clinical trial.

BACKGROUND: Proton pump inhibitors may foster intestinal dysbiosis and related bowel symptoms. AIM: To evaluate the effect of Lactobacillus paracasei F19 on bowel symptom onset in patients on long-term proton pump inhibitors. METHODS: In this randomized, double-blind, placebo-controlled study, patients with typical gastroesophageal reflux disease symptoms receiving pantoprazole 40 mg/d for six months were randomly assigned to receive: (A) Lactobacillus paracasei F19 bid for three days/week for six months; (B) placebo bid for three days/week for six months; (C) Lactobacillus paracasei F19 bid for three days/week for three months and placebo bid for three days/week for the following three months; (D) placebo bid for three days/week for three months and Lactobacillus paracasei F19 bid for three days/week for the following three months. Bloating, flatulence, abdominal pain and bowel habit were assessed monthly. RESULTS: 100/312 patients were enrolled. In the parallel groups, the treatment-by-time interaction affected bloating (p = 0.015), while Lactobacillus paracasei F19 treatment alone affected flatulence (p = 0.011). Moreover, the treatment-by-time interaction significantly affected the mean score of bloating (p = 0.01) and flatulence (p < 0.0001), the mean stool form (p = 0.03) and mean stool frequency/week (p = 0.016). Analysis of the cross-over groups, limited to the first three months because of carry-over effect, confirmed these results. CONCLUSION: Lactobacillus paracasei F19 supplementation prevents bowel symptom onset in patients on long-term proton pump inhibitors.