Marilia Carabotti

Helicobacter pylori infection in obesity and its clinical outcome after bariatric surgery

The present review summarizes the prevalence and active clinical problems in obese patients with Helicobacter pylori (H. pylori) infection, as well as the outcomes after bariatric surgery in this patient population. The involvement of H. pylori in the pathophysiology of obesity is still debated. It may be that the infection is protective against obesity, because of the gastritis-induced decrease in production and secretion of the orexigenic hormone ghrelin. However, recent epidemiological studies have failed to show an association between H. pylori infection and reduced body mass index. H. pylori infection might represent a limiting factor in the access to bariatric bypass surgery, even if high-quality evidence indicating the advantages of preoperative H. pylori screening and eradication is lacking. The clinical management of infection is complicated by the lower eradication rates with standard therapeutic regimens reported in obese patients than in the normal-weight population. Prospective clinical studies to ameliorate both H. pylori eradication rates and control the clinical outcomes of H. pylori infection after different bariatric procedures are warranted.

Postbiotic activities of lactobacilli-derived factors.

Probiotics are alive nonpathogenic microorganisms present in the gut microbiota that confer benefits to the host for his health. They act through molecular and cellular mechanisms that contrast pathogen bacteria adhesion, enhance innate immunity, decrease pathogen-induced inflammation, and promote intestinal epithelial cell survival, barrier function, and protective responses. Some of these beneficial effects result to be determined by secreted probiotic-derived factors that recently have been identified as “postbiotic” mediators. They have been reported for several probiotic strains but most available literature concerns Lactobacilli. In this review, we focus on the reported actions of several secretory products of different Lactobacillus species highlighting the available mechanistic data. The identification of soluble factors mediating the beneficial effects of probiotics may present an opportunity not only to understand their fine mechanisms of action, but also to develop effective pharmacological strategies that could integrate the action of treatments with live bacteria.

Cellular and Molecular Mechanisms of Phenotypic Switch in Gastrointestinal Smooth Muscle

As a general rule, smooth muscle cells (SMC) are able to switch from a contractile phenotype to a less mature synthetic phenotype. This switch is accompanied by a loss of differentiation with decreased expression of contractile markers, increased proliferation as well as the synthesis and the release of several signaling molecules such as pro‐inflammatory cytokines, chemotaxis‐associated molecules, and growth factors. This SMC phenotypic plasticity has extensively been investigated in vascular diseases, but interest is also emerging in the field of gastroenterology. It has in fact been postulated that altered microenvironmental conditions, including the composition of microbiota, could trigger the remodeling of the enteric SMC, with phenotype changes and consequent alterations of contraction and impairment of gut motility. Several molecular actors participate in this phenotype remodeling. These include extracellular molecules such as cytokines and extracellular matrix proteins, as well as intracellular proteins, for example, transcription factors. Epigenetic control mechanisms and miRNA have also been suggested to participate. In this review key roles and actors of smooth muscle phenotypic switch, mainly in GI tissue, are described and discussed in the light of literature data available so far. J. Cell. Physiol. 231: 295–302, 2016.

Role of Fiber in Symptomatic Uncomplicated Diverticular Disease: A Systematic Review

Symptomatic uncomplicated diverticular disease (SUDD) is a syndrome characterized by recurrent abdominal symptoms in patients with colonic diverticula. There is some evidence that a high-fiber diet or supplemental fibers may reduce symptoms in SUDD patients and a high-fiber diet is commonly suggested for these patients. This systematic review aims to update the evidence on the efficacy of fiber treatment in SUDD, in terms of a reduction in symptoms and the prevention of acute diverticulitis. According to PRISMA, we identified studies on SUDD patients treated with fibers (PubMed and Scopus). The quality of these studies was evaluated by the Jadad scale. The main outcome measures were a reduction of abdominal symptoms and the prevention of acute diverticulitis. Nineteen studies were included, nine with dietary fiber and 10 with supplemental fiber, with a high heterogeneity concerning the quantity and quality of fibers employed. Single studies suggest that fibers, both dietary and supplemental, could be beneficial in SUDD, even if the quality is very low, with just one study yielding an optimal score. The presence of substantial methodological limitations, the heterogeneity of the therapeutic regimens employed, and the lack of ad hoc designed studies, did not permit a summary of the outcome measure. Thus, the benefit of dietary or supplemental fiber in SUDD patients still needs to be established.

Upper gastrointestinal symptoms in obese patients and their outcomes after bariatric surgery

Obesity is considered an important risk factor for the development of gastrointestinal (GI) disorders, likely through alterations of GI motility. Even though gastroesophageal reflux disease is the condition mainly studied at present, the prevalence of other upper GI symptoms is also augmented in obese patients. Owing to their chronic trend, these disorders have a bearing on public spending and their correct diagnosis would avoid unnecessary cost-consuming investigations. Furthermore, bariatric surgery dramatically changes GI anatomy and physiology, influencing GI symptom outcomes. The aim of this review is to categorize the available results in a pathophysiological framework in an attempt to set up the correct clinical GI management of obese patients before and after bariatric surgery. This would be helpful in tentatively reducing their considerable economic burden on public health services.

Treatment of diverticular disease: an update on latest evidence and clinical implications

Background Diverticular disease (DD) is a common condition, especially in Western countries. In about 80% of patients, colonic diverticula remain asymptomatic (diverticulosis), while approximately 20% of patients may develop abdominal symptoms (symptomatic uncomplicated diverticular disease, SUDD) and, eventually complications as acute diverticulitis (AD). The management of this condition has been improved, and in the last five years European countries and the USA have published guidelines and recommendations. Scope To summarize the latest evidence and clinical implication in treatment of DD focusing the attention either on the treatment of diverticulosis, SUDD and AD together with the primary and secondary prevention of diverticulitis. Findings The present review was based on the latest evidence in the treatment of DD in the last 10 years. In the last 5 years, six countries issued guidelines on DD with differences regarding covered topics and recommendations regarding treatments. At present there is a lack of rationale for drug use in patients with asymptomatic diverticulosis, but there are limited indications to suggest an increase in dietary fibre to reduce risk of DD. To achieve symptomatic relief in SUDD patients, several therapeutic strategies with fibre, probiotics, rifaximin and mesalazine have been proposed even if a standard therapeutic approach remained to be defined. Agreement has been reached for the management of AD, since recent guidelines showed that antibiotics can be used selectively, rather than routinely in uncomplicated AD, although use of antibiotics remained crucial in the management of complicated cases. With regard to treatment for the primary and secondary prevention of AD, the efficacy of rifaximin and mesalazine has been proposed although with discordant recommendations among guidelines. Conclusion Treatment of DD represented an important challenge in clinical practice, especially concerning management of SUDD and the primary and secondary prevention of AD.

Upper gastrointestinal symptoms in autoimmune gastritis: A cross-sectional study

Abstract Autoimmune gastritis is often suspected for its hematologic findings, and rarely the diagnosis is made for the presence of gastrointestinal symptoms. Aims of this cross-sectional study were to assess in a large cohort of patients affected by autoimmune gastritis the occurrence and the pattern of gastrointestinal symptoms and to evaluate whether symptomatic patients are characterized by specific clinical features. Gastrointestinal symptoms of 379 consecutive autoimmune gastritis patients were systematically assessed and classified following Rome III Criteria. Association between symptoms and anemia pattern, positivity to gastric autoantibodies, Helicobacter pylori infection, and concomitant autoimmune disease were evaluated. In total, 70.2% of patients were female, median age 55 years (range 17–83). Pernicious anemia (53.6%), iron deficiency anemia (34.8%), gastric autoantibodies (68.8%), and autoimmune disorders (41.7%) were present. However, 56.7% of patients complained of gastrointestinal symptoms, 69.8% of them had exclusively upper symptoms, 15.8% only lower and 14.4% concomitant upper and lower symptoms. Dyspepsia, subtype postprandial distress syndrome was the most represented, being present in 60.2% of symptomatic patients. Univariate and multivariate analyses showed that age <55 years (OR 1.6 [CI:1–2.5]), absence of smoking habit (OR 2.2 [CI:1.2–4]), and absence of anemia (OR 3.1 [CI:1.5–6.4]) were independent factors associated to dyspepsia. Autoimmune gastritis is associated in almost 60% of cases with gastrointestinal symptoms, in particular dyspepsia. Dyspepsia is strictly related to younger age, no smoking, and absence of anemia.

Demographic and clinical features distinguish subgroups of diverticular disease patients: Results from an Italian nationwide registry:

Background Clinical features and lifestyle factors associated with diverticulosis compared to diverticular disease (DD), either symptomatic uncomplicated diverticular disease (SUDD) or in patients who have had previous diverticulitis (PD), are unclear. Objective The objective of this article is to compare cross-sectionally demographic and clinical features and quality of life (QoL) in diverticulosis, SUDD and PD patients. Methods The REMAD Registry is a prospective, observational, multicentre, cohort study. Patients were categorised according to: diverticulosis; SUDD (recurrent abdominal symptoms attributed to diverticula in absence of overt inflammation) and PD (≥1 previous diverticulitis). Results A total of 1217 patients (57.9% diverticulosis, 24.7% SUDD and 17.4% PD) were included. Compared to diverticulosis, female gender was associated to SUDD (OR 1.94; 95% CI: 1.43–2.62) and PD (OR 1.79; 95% CI: 1.24–2.56); age ≤ 60 years was associated to PD (OR 2.10; 95% CI: 1.42–3.08 vs diverticulosis, OR 1.57; 95% CI: 1.01–2.45 vs SUDD). PD patients showed an association with past bleeding (OR 29.29; 95% CI: 8.17–104.98 vs diverticulosis, OR 16.84; 95% CI: 3.77–75.25 vs SUDD). Compared to diverticulosis, family history for diverticula was associated to PD (OR 1.88; 95% CI: 1.27–2.78). Patients with diverticulosis showed higher QoL scores, both physical (p = 0.0001 and 0.0257) and mental (p < 0.0001 and 0.0038), in comparison to SUDD and PD. Conclusion Family history for diverticula and history of bleeding distinguish diverticulosis from DD. These clinical features should be kept in mind in the management of DD.

Cost of detecting gastric neoplasia by surveillance endoscopy in atrophic gastritis in Italy: A low risk country

BACKGROUND Atrophic gastritis (AG) is at increased risk of gastric neoplasia, thus surveillance gastroscopy has been proposed. AIMS To assess cost of detecting gastric neoplasias by surveillance endoscopy according to identified risk factors in Italy. METHODS Post-hoc analysis of a cohort study including 200 AG-patients from Italy followed up for a mean of 7.5 (4-23.4) years was done. Considered risk factors were: age >50years, extensive atrophy, pernicious anaemia, OLGA-OLGIM scores 3-4 at diagnosis. The number of 4-year-surveillance endoscopies needed to be performed to detect one gastric neoplasia (NNS) was calculated. RESULTS In 19 patients neoplasias (4 gastric cancers, 8 type 1 gastric carcinoids, 7 dysplasias) were detected at the 361 surveillance gastroscopies, corresponding to NNS of 19 and a cost per gastric neoplastic lesion of €2945. By restricting surveillance to pernicious anaemia patients, reduction of NNS and cost per neoplasia to 13.8 and €2139 may be obtained still detecting 74% of neoplasias. By limiting the surveillance to pernicious anaemia patients and OLGA 3-4, 5 (26.3%) neoplasias would have been detected with a corresponding NNS of 5.4 and a cost per lesion of €837. CONCLUSION Risk factors may allow an efficient allocation of financial and medical resources for endoscopic surveillance in AG in a low risk country.

Luminescent Immunoprecipitation System (LIPS) for Detection of Autoantibodies Against ATP4A and ATP4B Subunits of Gastric Proton Pump H+,K+-ATPase in Atrophic Body Gastritis Patients

OBJECTIVES: Circulating autoantibodies targeting the H+/K+‐ATPase proton pump of gastric parietal cells are considered markers of autoimmune gastritis, whose diagnostic accuracy in atrophic body gastritis, the pathological lesion of autoimmune gastritis, remains unknown. This study aimed to assess autoantibodies against ATP4A and ATP4B subunits of parietal cells H+, K+‐ATPase in atrophic body gastritis patients and controls. METHODS: One‐hundred and four cases with atrophic body gastritis and 205 controls were assessed for serological autoantibodies specific for ATP4A or ATP4B subunits using luminescent immunoprecipitation system (LIPS). Recombinant luciferase‐reporter‐fused‐antigens were expressed by in vitro transcription‐translation (ATP4A) or after transfection in Expi293F cells (ATP4B), incubated with test sera, and immune complexes recovered using protein‐A‐sepharose. LIPS assays were compared with a commercial enzyme immunoassay (EIA) for parietal cell autoantibodies. RESULTS: ATP4A and ATP4B autoantibody titers were higher in cases compared to controls (P<0.0001). The area under the receiver‐operating characteristic curve was 0.98 (95% CI 0.965–0.996) for ATP4A, and 0.99 (95% CI 0.979–1.000) for ATP4B, both higher as compared with that of EIA: 0.86 (95% CI 0.809–0.896), P<0.0001. Sensitivity‐specificity were 100–89% for ATP4A and 100–90% for ATP4B assay. Compared with LIPS, EIA for parietal cell autoantibodies showed a lower sensitivity (72%, P<0.0001) at a similar specificity (92%, P=0.558). CONCLUSIONS: Positivity to both, ATP4A and ATP4B autoantibodies is closely associated with atrophic body gastritis. Both assays had the highest sensitivity, at the cost of diagnostic accuracy (89 and 90% specificity), outperforming traditional EIA. Once validated, these LIPS assays should be valuable screening tools for detecting biomarkers of damaged atrophic oxyntic mucosa.