The Gastropack Access System as a Model to Access Gastroenterology Services for Gastroscopy Appropriateness in Patients with Upper Gastrointestinal Symptoms: A Comparison with the Open Access System.

Esophagogastroduodenoscopy (EGD) appropriateness in Open-Access System (OAS) is a relevant issue. The Gastropack Access System (GAS) is a new system to access gastroenterological services, based on the partnership between Gastroenterologists and GPs. This study aims to evaluate if GAS is superior to OAS in terms of EGDS appropriateness. Secondarily, we evaluated the diagnostic yield of EGDS according to ASGE guidelines. The GAS was developed in an area of Bologna where General Practitioners (GPs) could decide to directly prescribe EGDS through OAS or referring to GAS, where EGDS can be scheduled after contact between GPs and specialists sharing a patient's clinical information. Between 2016 and 2019, 2179 cases (M:F = 861:1318, median age 61, IQR 47.72) were referred to GAS and 1467 patients (65%) had a prescription for EGDS; conversely, 874 EGDS were prescribed through OAS (M:F = 383:491; median age 58 yrs, IQR 45.68). Indication was appropriate in 92% in GAS (1312/1424) versus 71% in OAS (618/874), p < 0.001. The rate of clinically significant endoscopic findings (CSEF) was significantly higher in GAS (49% vs. 34.8%, p < 0.001). Adherence to ASGE guidelines was not related to CSEF; however, surveillance for pre-malignant conditions was independently related to CSEF. All neoplasm were observed in appropriate EGD. GAS is an innovative method showing extremely high rates of appropriateness. ASGE guidelines confirmed their validity for cancer detection, but their performance for the detection of other conditions needs to be refined.

[Diet and gut microbiota: two sides of the same coin?] / Dieta e microbiota intestinale: due facce di una stessa medaglia?

Gut microbiota is a complex ecosystem, resident in the digestive tract, exerting multiple functions that can have a significant impact on the pathophysiology of the host organism. The composition and functions of this "superorganism" are influenced by many factors, and among them, the host's dietary habits seem to have a significant effect. Dietary changes in the evolution of human history and in the different stages of life of the human subjects are responsible for qualitative and functional modification of gut microbiota. At the same time, the different dietary models adopted in worldwide geographic areas take into account the inter-individual differences concerning composition and microbial function. This close relationship between diet, gut microbiota and host seems, in fact, to be responsible for the protection or predisposition to develop several metabolic, immunological, neoplastic and functional diseases. Thus, several studies have evaluated the impact of diet and lifestyle modification strategies on gut microbiota composition and functions which, in turn, seems to affect the effectiveness of such therapeutic measures. Gut microbiota manipulation strategies, as complementary to dietary modifications, represent a fascinating field of research, even if consolidated data are still lacking.

Gut Microbiota and Celiac Disease.

Recent evidence regarding celiac disease has increasingly shown the role of innate immunity in triggering the immune response by stimulating the adaptive immune response and by mucosal damage. The interaction between the gut microbiota and the mucosal wall is mediated by the same receptors which can activate innate immunity. Thus, changes in gut microbiota may lead to activation of this inflammatory pathway. This paper is a review of the current knowledge regarding the relationship between celiac disease and gut microbiota. In fact, patients with celiac disease have a reduction in beneficial species and an increase in those potentially pathogenic as compared to healthy subjects. This dysbiosis is reduced, but might still remain, after a gluten-free diet. Thus, gut microbiota could play a significant role in the pathogenesis of celiac disease, as described by studies which link dysbiosis with the inflammatory milieu in celiac patients. The use of probiotics seems to reduce the inflammatory response and restore a normal proportion of beneficial bacteria in the gastrointestinal tract. Additional evidence is needed in order to better understand the role of gut microbiota in the pathogenesis of celiac disease, and the clinical impact and therapeutic use of probiotics in this setting.

Pathophysiology and Therapeutic Strategies for Symptomatic Uncomplicated Diverticular Disease of the Colon.

Colonic diverticulosis imposes a significant burden on industrialized societies. The current accepted causes of diverticula formation include low fiber content in the western diet with decreased intestinal content and size of the lumen, leading to the transmission of muscular contraction pressure to the wall of the colon, inducing the formation of diverticula usually at the weakest point of the wall where penetration of the blood vessels occurs. Approximately 20 % of the patients with colonic diverticulosis develop abdominal symptoms (i.e., abdominal pain and discomfort, bloating, constipation, and diarrhea), a condition which is defined as symptomatic uncomplicated diverticular disease (SUDD). The pathogenesis of SUDD symptoms remains uncertain and even less is known about how to adequately manage bowel symptoms. Recently, low-grade inflammation, altered intestinal microbiota, visceral hypersensitivity, and abnormal colonic motility have been identified as factors leading to symptom development, thus changing and improving the therapeutic approach. In this review, a comprehensive search of the literature regarding on SUDD pathogenetic hypotheses and pharmacological strategies was carried out. The pathogenesis of SUDD, although not completely clarified, seems to be related to an interaction between colonic microbiota alterations, and immune, enteric nerve, and muscular system dysfunction (Cuomo et al. in United Eur Gastroenterol J 2:413-442, 2014). Greater understanding of the inflammatory pathways and gut microbiota composition in subjects affected by SUDD has increased therapeutic options, including the use of gut-directed antibiotics, mesalazine, and probiotics (Bianchi et al. in Aliment Pharmacol Ther 33:902-910, 2011; Comparato et al. in Dig Dis Sci 52:2934-2941, 2007; Tursi et al. in Aliment Pharmacol Ther 38:741-751, 2013); however, more research is necessary to validate the safety, effectiveness, and cost-effectiveness of these interventions.

Liver and spleen stiffness and other noninvasive methods to assess portal hypertension in cirrhotic patients: a review of the literature.

Portal hypertension (PH) is one of the most important causes of morbidity and mortality in patients with chronic liver disease. PH measurement is crucial to stage and predict the clinical outcome of liver cirrhosis. Measurement of hepatic vein pressure gradient is considered the gold standard for assessment of the degree of PH; however, it is an invasive method and has not been used widely. Thus, noninvasive methods have been proposed recently. We critically evaluated serum markers, abdominal ultrasonography, and particularly liver and spleen stiffness measurement, which represent the more promising methods to stage PH degree and to assess the presence/absence of esophageal varices (EV). A literature search was carried out on MEDLINE, EMBASE, Web of Science, and Scopus for articles and abstracts. The search terms used included 'liver cirrhosis', 'portal hypertension', 'liver stiffness', 'spleen stiffness', 'ultrasonography', and 'portal hypertension serum biomarker'. The articles cited were selected on the basis of their relevance to the objective of the review. The results of available studies indicate that individually, these methods have a mild accuracy in predicting the presence of EV, and thus they cannot substitute endoscopy to predict EV. When these tests were used in combination, their accuracy increased. In addition to the PH staging, several serum markers and spleen stiffness measurement can predict the clinical outcome of liver cirrhosis with a good accuracy, comparable to that of hepatic vein pressure gradient. In the future, noninvasive methods could be used to select patients requiring further investigations to identify the best tailored clinical management.

Non-invasive diagnostic approach to non-alcoholic fatty liver disease: current evidence and future perspectives.

Non-alcoholic fatty liver disease is a new epidemic liver disease, thus, its early diagnosis and the identification of those patients with the worst prognosis is mandatory. Liver biopsy is still the diagnostic gold standard, even if it is associated to a significant rate of complications; moreover, the interpretation of histological samples is not always univocal. Several non-invasive alternative scores have been proposed for the diagnostic approach to non-alcoholic fatty liver disease. This article evaluates the performance of the currently available non-invasive diagnostic strategies. The authors also suggest a potential diagnostic algorithm, with two or more non-invasive techniques, to increase the overall accuracy for identifying patients with worst prognosis, and to minimize the recourse to liver biopsy.

Gut microbiota and metabolic syndrome.

Gut microbiota exerts a significant role in the pathogenesis of the metabolic syndrome, as confirmed by studies conducted both on humans and animal models. Gut microbial composition and functions are strongly influenced by diet. This complex intestinal "superorganism" seems to affect host metabolic balance modulating energy absorption, gut motility, appetite, glucose and lipid metabolism, as well as hepatic fatty storage. An impairment of the fine balance between gut microbes and host's immune system could culminate in the intestinal translocation of bacterial fragments and the development of "metabolic endotoxemia", leading to systemic inflammation and insulin resistance. Diet induced weight-loss and bariatric surgery promote significant changes of gut microbial composition, that seem to affect the success, or the inefficacy, of treatment strategies. Manipulation of gut microbiota through the administration of prebiotics or probiotics could reduce intestinal low grade inflammation and improve gut barrier integrity, thus, ameliorating metabolic balance and promoting weight loss. However, further evidence is needed to better understand their clinical impact and therapeutic use.

Prognostic factors for hepatocellular carcinoma recurrence.

The recurrence of hepatocellular carcinoma, the sixth most common neoplasm and the third leading cause of cancer-related mortality worldwide, represents an important clinical problem, since it may occur after both surgical and medical treatment. The recurrence rate involves 2 phases: an early phase and a late phase. The early phase usually occurs within 2 years after resection; it is mainly related to local invasion and intrahepatic metastases and, therefore, to the intrinsic biology of the tumor. On the other hand, the late phase occurs more than 2 years after surgery and is mainly related to de novo tumor formation as a consequence of the carcinogenic cirrhotic environment. Since recent studies have reported that early and late recurrences may have different risk factors, it is clinically important to recognize these factors in the individual patient as soon as possible. The aim of this review was, therefore, to identify predicting factors for the recurrence of hepatocellular carcinoma, by means of invasive and non-invasive methods, according to the different therapeutic strategies available. In particular the role of emerging techniques (e.g., transient elastography) and biological features of hepatocellular carcinoma in predicting recurrence have been discussed. In particular, invasive methods were differentiated from non-invasive ones for research purposes, taking into consideration the emerging role of the genetic signature of hepatocellular carcinoma in order to better allocate treatment strategies and surveillance follow-up in patients with this type of tumor.

Spleen stiffness measurement can predict clinical complications in compensated HCV-related cirrhosis: a prospective study.

BACKGROUND & AIMS: Hepatic venous pressure gradient (HVPG) measurement represents the best predictor of clinical decompensation (CD) in cirrhotic patients. Recently data show that measurement of spleen stiffness (SS) has an excellent correlation with HVPG levels. Aim of the present prospective study was to assess SS predictive value for CD compared to HVPG, liver stiffness (LS), and other non-invasive tests for portal hypertension in a cohort of patients with HCV-related compensated cirrhosis. METHODS: From an initial cohort of 124 patients, 92 underwent baseline LS, SS, HVPG measurements and upper gastrointestinal endoscopy at enrolment and then followed-up for 2 years or until the occurrence of the first CD. Univariate and multivariate logistic regression models were used for determining judgement criteria associated parameters. Accuracy of predictive factors was evaluated using c statistic. The final model was internally validated using the bootstrap method. RESULTS: During follow-up, 30 out 92 (32.6%) patients developed CD. At univariate analysis varices at enrolment, all non-invasive parameters, HVPG, and model for end-stage liver disease (MELD) resulted clinical predictors of CD. At multivariate analysis only SS (p=0.0001) and MELD (p=0.014) resulted as predictive factors. A decision algorithm based on the results of a predictive model was proposed to detect patients with low risk of decompensation. CONCLUSIONS: This study shows that in compensated cirrhotic patients a SS and MELD predictive model represents an accurate predictor of CD with accuracy at least equivalent to that of HVPG. If confirmed by further studies, SS and MELD could represent valid alternatives to HVPG as prognostic indicator of CD in HCV-related cirrhosis.

Measurement of spleen stiffness to evaluate portal hypertension and the presence of esophageal varices in patients with HCV-related cirrhosis.

BACKGROUND & AIMS: The hepatic vein pressure gradient (HVPG) is the standard used to determine the degree of portal hypertension (PH) and an important prognostic factor for patients with cirrhosis; HVPG values correlate with the presence of esophageal varices (EV). However, HVPG can only be accurately determined at specialized centers; noninvasive methods are needed to predict HVPG values and the presence of EV. We compared the diagnostic performance of spleen stiffness (SS) measurement by transient elastography with that of liver stiffness (LS) and of other recently proposed noninvasive tests. METHODS: We measured SS and LS in 100 consecutive patients with hepatitis C virus-induced cirrhosis. Patients were also assessed by FibroScan, HVPG, esophagogastroduodenoscopy, and liver biopsy. We also analyzed LS-spleen diameter to platelet ratio score and platelet count to spleen diameter. RESULTS: SS and LS were more accurate than other noninvasive parameters in identifying patients with EV and different degrees of PH. A linear model that included SS and LS accurately predicted HVPG values (R(2) = 0.85). The results were internally validated using bootstrap analysis. CONCLUSIONS: Measurement of SS can be used for noninvasive assessment and monitoring of PH and to detect EV in patients with hepatitis C virus-induced cirrhosis.

Gut microbiota and its pathophysiology in disease paradigms.

The gut flora carries out important functions for human health, although most of them are still unknown, and an alteration of any of them, due to a condition of dysbiosis, can lead to relevant pathological implications. Commensal bacteria in the gut are essential for the preservation of the integrity of the mucosal barrier function and an alteration in the anatomic functional integrity of this barrier has been implicated in the pathophysiologic process of different diseases. The gut microflora plays a role in modulating the intestinal immune system; in fact, it is essential for the maturation of gut-associated lymphatic tissue, the secretion of IgA and the production of antimicrobial peptides. The enteric flora represents a potent bioreactor which controls several metabolic functions, even if most of them are still unknown. The main metabolic functions are represented by the fermentation of indigestible food substances into simple sugars, absorbable nutrients, and short-chain fatty acids. Furthermore, the gut microbiota exerts important trophic and developmental functions on the intestinal mucosa. This overview focuses briefly on the physiological role of the gut microbiota in maintaining a healthy state and the potential role played by disturbances of both the function and composition of the gut microbiota in determining important pathological conditions, such as irritable bowel syndrome, inflammatory bowel disease, metabolic syndrome, obesity, and cancer.