Covid-19: exploring the "new normal" in gastroenterology training.

The coronavirus disease 2019 (COVID-19) pandemic has led to unprecedented disruptions in fellowship training programs worldwide. In gastroenterology, the strain in healthcare service provision and the emphasis on preventing viral transmission has adversely impacted hands-on training opportunities, with trainees facing the constant pressure to meet training requirements under the continuous threat of viral transmission. Emerging evidence highlight the scale of the problem, specifically with regard to endoscopy competence due to cancellation of elective endoscopic procedures, provision of inpatient and outpatient consultative care as well as academic education and the mental well-being of trainees. As such, it has been necessary for trainees, trainers and training programs collectively to adapt to these challenges and incorporate novel and adaptive solutions to circumvent these training barriers. This review aims to summarise data on the global impact of COVID-19 on gastroenterology training and the practical interventions that could be implemented.

Management of Helicobacter pylori infection-the Maastricht V/Florence Consensus Report.

Important progress has been made in the management of Helicobacter pylori infection and in this fifth edition of the Maastricht Consensus Report, key aspects related to the clinical role of H. pylori were re-evaluated in 2015. In the Maastricht V/Florence Consensus Conference, 43 experts from 24 countries examined new data related to H. pylori in five subdivided workshops: (1) Indications/Associations, (2) Diagnosis, (3) Treatment, (4) Prevention/Public Health, (5) H. pylori and the Gastric Microbiota. The results of the individual workshops were presented to a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in the various clinical scenarios.

Colon neoplasia in patients with type 2 diabetes on metformin: A meta-analysis.

BACKGROUND: A growing body of evidence has suggested that metformin potentially reduces the risk of cancer. OBJECTIVE: We performed a meta-analysis of available studies to better define the effect of metformin on colon neoplasia (cancer and polyps) in patients with type 2 diabetes. METHODS: Medical literature searches for human studies were performed through December 2015, using suitable keywords. Pooled estimates were obtained using fixed or random-effects models. Heterogeneity between studies was evaluated with the Cochran Q test whereas the likelihood of publication bias was assessed by constructing funnel plots. Their symmetry was estimated by the Begg and Mazumdar adjusted rank correlation test and by the Egger's regression test. In addition subgroup and sensitivity analyses were performed. RESULTS: A total number of 709,980 patients, with type 2 diabetes, were included in 17 studies eligible for meta-analysis [1 RCT and 16 observational studies (13 cohort and 3 case-controls)]. The risk of colon neoplasia was significantly lower among metformin users than controls (non-metformin users) [pooled RRs (95% CI)=0.75 (0.65-0.87), test for overall effect Z=-3.95, p<0.001]. This observation applied separately for colon cancer [0.79 (0.69-0.91), Z=-3.34, p<0.001] and for colon polyps [0.58 (0.42-0.80), Z=-3.30, p<0.001]. CONCLUSION: This meta-analysis shows that the use of metformin in patients with type 2 diabetes is associated with significantly lower risk of colon neoplasia.

The association between Helicobacter pylori infection and inflammatory bowel disease based on meta-analysis.

BACKGROUND: In humans there are epidemiological data suggesting a protective effect of Helicobacter pylori (H. pylori) infection against the development of autoimmune diseases and in addition, there are laboratory data illustrating H. pylori's ability to induce immune tolerance and limit inflammatory responses. Thus, numerous observational studies have examined the association between H. pylori infection and inflammatory bowel disease (IBD) with various results. OBJECTIVE: We performed a meta-analysis of available studies to better define the association of H. pylori infection and IBD. METHODS: Medical literature searches for human studies were performed through September 2014, using suitable keywords. In each study the risk ratio (RR) of H. pylori infection in IBD patients vs controls was calculated and pooled estimates were obtained using fixed- or random-effects models as appropriate. Heterogeneity between studies was evaluated using Cochran Q test and I(2) statistics, whereas the likelihood of publication bias was assessed by constructing funnel plots. RESULTS: Thirty-three studies were eligible for meta-analysis, including 4400 IBD patients and 4763 controls. Overall 26.5% of IBD patients were positive for H. pylori infection, compared to 44.7% of individuals in the control group. There was significant heterogeneity in the included studies (Q = 137.2, df (Q) =32, I(2) ( )= 77%, p < 0.001) and therefore the random-effects model of meta-analysis was used. The obtained pool RR estimation was 0.62 (95% confidence interval (CI) 0.55-0.71, test for overall effect Z = -7.04, p < 0.001). There was no evidence of publication bias. CONCLUSION: The results of this meta-analysis showed a significant negative association between H. pylori infection and IBD that supports a possible protective benefit of H. pylori infection against the development of IBD.

Does purgative preparation influence the diagnostic yield of small bowel video capsule endoscopy?: A meta-analysis.

OBJECTIVES: Video capsule endoscopy (VCE) is a useful tool in investigating small bowel pathology. However, the role of bowel preparation is controversial. Therefore, the aim of this study was to explore the role of bowel preparation and in particular its consequences on diagnostic yield in a meta-analysis of all relevant studies. METHODS: Extensive English-language medical literature searches were performed up to February 2008, using suitable keywords, looking for human studies that compared different modes of small bowel preparation (purgative vs. clear liquids diet). We examined the effects of this preparation on the following three primary end points, diagnostic yield (DY), small bowel visualization quality (SBVQ), and VCE completion rate (CR) by meta-analysis of relevant studies. RESULTS: A total of 12 eligible studies (6 prospective, 6 retrospective) were identified, including 16 sets of data relevant to our primary end points. There were significant differences between patients prepared with purgative vs. those prepared with clear liquids diet in DY (263 vs. 213 patients, respectively; OR (95% CI)=1.813 (1.251-2.628), P=0.002) and SBVQ (404 vs. 249 patients, respectively; OR (95% CI)=2.113 (1.252-3.566), P=0.005). There was no statistically significant difference regarding CR rate. Purgatives did not affect VCE gastric transit time (GTT) or VCE small bowel transit time (SBTT). CONCLUSIONS: Pooled data showed that in comparison to clear liquids diet, purgative bowel cleansing, before VCE, improves the SBVQ and increases the DY of the examination, but does not affect the VCE completion rate.

Video-capsule endoscopy gastric and small bowel transit time and completeness of the examination in patients with diabetes mellitus.

BACKGROUND: Small intestine video-capsule endoscopy examination in patients with diabetes mellitus may be incomplete due to delayed gastric emptying. AIM: To measure video-capsule endoscopy gastric and small bowel transit time and to assess the completeness of the examination in diabetes mellitus patients. METHODS: In this retrospective, case-control study, we examined capsule endoscopy videos from 29 consecutive diabetes mellitus patients. Fifty-eight matched for sex, type of preparation, age and reason for referral non-diabetic controls were selected from our video-capsule endoscopy database. Two independent experienced investigators measured transit times and assessed examinations' completeness. RESULTS: Video-capsule endoscopy gastric transit time was significantly longer in diabetes mellitus (87, 1-478 min) compared to non-diabetic patients (24, 4-108 min, p<0.001). The caecum was visualized in 20/29 (69%) diabetes mellitus and 52/58 (89.6%) non-diabetic controls (p=0.02). In 16 diabetes mellitus patients that video-capsule endoscopy reached the caecum, small bowel transit time was significantly shorter (261.2+/-55.5 min) compared to their 32 non-diabetic matched controls (302+/-62.7 min, p=0.03). CONCLUSIONS: Patients with type 2 diabetes mellitus have prolonged video-capsule endoscopy gastric transit time compared to non-diabetic patients. Prospective studies are required to complete our understanding of video-capsule endoscopy transit times in the setting of diabetes mellitus.

Current concepts in the management of Helicobacter pylori infection: the Maastricht III Consensus Report.

BACKGROUND: Guidelines on the management of Helicobacter pylori, which cover indications for management and treatment strategies, were produced in 2000. AIMS: To update the guidelines at the European Helicobacter Study Group (EHSG) Third Maastricht Consensus Conference, with emphasis on the potential of H pylori eradication for the prevention of gastric cancer. RESULTS: Eradication of H pylori infection is recommended in (a) patients with gastroduodenal diseases such as peptic ulcer disease and low grade gastric, mucosa associated lymphoid tissue (MALT) lymphoma; (b) patients with atrophic gastritis; (c) first degree relatives of patients with gastric cancer; (d) patients with unexplained iron deficiency anaemia; and (e) patients with chronic idiopathic thrombocytopenic purpura. Recurrent abdominal pain in children is not an indication for a "test and treat" strategy if other causes are excluded. Eradication of H pylori infection (a) does not cause gastro-oesophageal reflux disease (GORD) or exacerbate GORD, and (b) may prevent peptic ulcer in patients who are naïve users of non-steroidal anti-inflammatory drugs (NSAIDs). H pylori eradication is less effective than proton pump inhibitor (PPI) treatment in preventing ulcer recurrence in long term NSAID users. In primary care a test and treat strategy using a non-invasive test is recommended in adult patients with persistent dyspepsia under the age of 45. The urea breath test, stool antigen tests, and serological kits with a high accuracy are non-invasive tests which should be used for the diagnosis of H pylori infection. Triple therapy using a PPI with clarithromycin and amoxicillin or metronidazole given twice daily remains the recommended first choice treatment. Bismuth-containing quadruple therapy, if available, is also a first choice treatment option. Rescue treatment should be based on antimicrobial susceptibility. CONCLUSION: The global burden of gastric cancer is considerable but varies geographically. Eradication of H pylori infection has the potential to reduce the risk of gastric cancer development.

Performance of two immunosorbent assay kits for the detection of serum immunoglobulin G to Helicobacter pylori in untreated greek patients.

BACKGROUND: The performance of serological methods used to detect Helicobacter pylori varies with the ethnicity and prevalence of the infection in the community. We have prospectively evaluated the performance of two commercially available serum enzyme immunoassays (EIA) detecting H. pylori immunoglobulin G (IgG) antibodies in the sera of untreated Greek patients. METHODS: One-hundred-and-thirty consecutive untreated dyspeptic patients underwent endoscopy with biopsies from the gastric body (n = 2) and antrum (n = 2). Serum samples were also obtained from each patient. Serum H. pylori IgG antibody titres were determined with two EIA kits (Pyloriset EIA-G and Milenia H. pylori IgG). Sensitivities, specificities and optimal cut-off values of serum EIAs were determined for the population under investigation by using receiver operating characteristic (ROC) curve analysis and histology as gold standard. RESULTS: Ninety-seven patients were defined H. pylori-positive and 33 negative by histology. ROC curve analysis for the Pyloriset kit yielded 86% (95% CI, 78%-92%) sensitivity and 85% (68%-95%) specificity at an optimal cut-off value of >358 units/ml. The respective values for the Milenia kit were 86% (78%-92%) and 82% (65%-93%) at an optimal cut-off value of >51 units/ml. The suggested cut-off values of the manufacturers for Pyloriset and Milenia kits are >300 and >44 EIA units, respectively, which yield 2% and 4% higher sensitivity, but 9% lower specificity for both EIA kits. CONCLUSIONS: Both serum EIA kits performed well in our study. Our data show that EIA cut-off values should be optimized for the population under investigation.

Evaluation of a single-step serological assay for laboratory diagnosis of Helicobacter pylori infection.

A rapid, single-step, in-laboratory qualitative test for the detection of IgG antibodies to Helicobacter pylori in serum (TestPack Plus; Abbott Laboratories, Germany) was evaluated. This test may be used as an alternative to enzyme immunoassays (EIAs). Of 153 adult patients, 110 were defined as Helicobacter pylori positive and 43 as Helicobacter pylori negative by the gold standard, a combination of three tests. The performance characteristics of the TestPack Plus, i.e. sensitivity, specificity, and positive and negative predictive values, were not significantly different from the corresponding values obtained with an EIA used for comparative purposes, the Pyloriset EIA-G test (Orion Diagnostica, Finland). The high positive predictive value (93%) of the TestPack Plus single-step serological test makes it a valuable tool for rapid in-laboratory screening purposes, especially in countries with a high prevalence of Helicobacter pylori infection.

Impact of H. pylori infection on the management of dyspepsia.

This review article refers to the impact which Helicobacter pylori infection has on the management of dyspepsia. The answer to the question of whether H. pylori eradication is clinically useful in dyspeptic patients or not remains a controversial and debatable subject. Nonetheless, the recent Maastricht 2 - 2000 Consensus Report, taking into account all the available data so far, concluded that a 'test-and-treat' approach to dyspepsia should be used in adult patients with persistent dyspepsia under the age of 45 years (the cutoff age may vary locally), having excluded those with predominantly gastroesophageal reflux disease symptoms, nonsteroidal anti-inflammatory drug users, and patients with alarm symptoms or a family history of gastric cancer.

Effectiveness of acid suppression in preventing gastroesophageal reflux disease (GERD) after successful treatment of Helicobacter pylori infection.

There is evidence that Helicobacter pylori eradication might predispose to gastroesophageal reflux disease (GERD). The aim of this prospective study was to examine the effectiveness of antisecretory treatment, after successful H. pylori eradication, in preventing GERD, since no data exist so far. Eighty initially H. pylori(+) patients, without GERD at the time of H. pylori eradication [50 peptic ulcer (PU) and 30 nonulcer (NU), 55 men, 25 women, median age 38 years, range 19-57], after successful H. pylori eradication were randomized to recieve either omeprazole 20 mg daily (group A) or no treatment (group B) for one year. All patients underwent upper gastrointestinal endoscopy at 0, 6, and 12 months or when GERD symptoms occurred. There were 40 patients in each group, and there were no statistically significant differences between the two groups in terms of sex, age, body weight, ulcer/no ulcer ratio, and other demographic data. Seven patients from group A and five patients from group B were lost to follow-up, and therefore there were 33 and 35 patients in groups A and B, respectively, who completed the study. One of 33 patients in group A (3%) and 10/35 (28.5%) in group B developed GERD symptoms during follow-up (P = 0.0022). The respective values for esophagitis were 0/33 (0%) and 6/35 (17.1%) (P = 0.0083). In conclusion, antisecretory treatment in H. pylori(+) patients, after successful eradication, is effective in preventing GERD.

The association between CagA status and the development of esophagitis after the eradication of Helicobacter pylori.

BACKGROUND: Strains of Helicobacter pylori with the cytotoxine-associated gene A (cagA) are linked to severe forms of gastroduodenal disease. Although eradication of H. pylori may predispose to the development of reflux esophagitis, the effects of CagA status on risk of esophagitis after successful H. pylori treatment are not known. METHODS: We studied 50 consecutive patients without esophagitis in whom H. pylori was eradicated successfully. CagA status was determined by immunoblotting sera from patients against H. pylori antigens. Patients underwent upper gastrointestinal endoscopy before eradication and 6, 12, 18, and 24 months after eradication or when reflux symptoms occurred. Biopsy specimens of the antrum and corpus were evaluated for gastritis before H. pylori eradication and at the end of the study. The sum of the scores for acute and chronic inflammation (both measured on a 0 [absent] to 3 [severe] scale) comprised the total gastritis severity score. RESULTS: In a multivariate proportional hazards regression analysis, positive CagA serology (hazard ratio [HR] = 10, 95% confidence interval [CI]: 1.3 to 81) and moderate-to-severe corpus gastritis (total severity score > or =4) before eradication (HR = 2.3, 95% CI: 1.2 to 6.1) were independent risk factors for the development of esophagitis after H. pylori eradication. CONCLUSION: Patients infected with strains of H. pylori that are cagA-positive are at increased risk of developing esophagitis after eradication of H. pylori.

Enhancement of bowel sounds by wavelet-based filtering.

This paper evaluates the performance of an automatic method for structural decomposition, noise removal and enhancement of bowel sounds (BS), based on the wavelet transform. The proposed method combines multiresolution analysis with hard thresholding to compose a wavelet transform-based stationary-nonstationary (WTST-NST) filter, for enhanced separation of bowel sounds (BS) from superimposed noise. Quantitative and qualitative analysis of the experimental results, when applying the WTST-NST filter to BS recorded from controls and patients with gastrointestinal dysfunction, prove that the ability of the WTST-NST filter to remove noise and reveal the authentic structure of BS is excellent. By eliminating the need to record a noise reference signal, this method reduces hardware overhead when analysis of BS is the primary aim. The method is independent of subjective human judgement for selection of noise reference templates, is robust to different levels of signal interference, and, due to its simplicity, can easily be used in clinical medicine.

Altered gastric epithelial cell kinetics in Helicobacter pylori-associated intestinal metaplasia: implications for gastric carcinogenesis.

We have compared apoptosis and proliferation in antral epithelium from individuals not infected with H. pylori (Hp), those with Hp-induced gastritis and those with Hp-induced gastritis containing areas of gastric intestinal metaplasia, the precursor lesion to gastric adenocarcinoma. Antral biopsies from 42 patients were assessed for evidence of Hp infection, severity of gastritis and intestinal metaplasia. Apoptosis was evaluated by the TUNEL assay and proliferation by Ki-67 immunohistochemistry and were expressed as apoptotic (AI) and proliferation (PI) indices. In the 31 Hp-positive (Hp(+)) patients, apoptosis and proliferation were increased compared with the 11 Hp-negative (Hp(-)) patients (AI = 1. 22 +/- 0.13% vs. 0.15 +/- 0.03%, p < 0.0001; PI = 24 +/- 1% vs. 13 +/- 2%, p < 0.0001). Increases were proportional to the severity of the inflammation. Within foci of intestinal metaplasia, in 9 of the Hp(+) patients, apoptosis was significantly reduced compared with surrounding gastritis (AI = 0.20 +/- 0.06% vs. 1.34 +/- 0.23%, p = 0. 0014), whereas proliferation was not altered (PI = 25.4 +/- 4% vs. 24.7 +/- 2%, p = 0.87), resulting in a lower AI/PI ratio in intestinal metaplasia than in surrounding gastritis (0.008 +/- 0.005 vs. 0.054 +/- 0.009, p < 0.02). Hp-induced gastritis is thus associated with increased epithelial apoptosis and proliferation compared with uninfected controls. In intestinal metaplasia, proliferation remains increased but apoptosis reverts to normal levels, and this perhaps contributes to Hp-associated gastric carcinogenesis.

Proliferating cell nuclear antigen (PCNA) immunostaining in Helicobacter pylori infection: impact of eradication.

Despite the fact that the association of Helicobacter pylori (H. pylori)with an increased risk of gastric cancer has been well documented, the exact mechanisms of this association have not been fully elucidated. The aim of the present prospective study was to contribute to the exploration of these mechanisms by studying the relationship between H. pylori infection and proliferating cell nuclear antigen (PCNA) immunostaining in endoscopic biopsies in gastric antrum. Furthermore, we examined the impact of H. pylorieradication on this relationship. We studied 28 H. pyloripositive patients and the results were compared with 22 endoscopically and histologically normal H. pylorinegative patients (control group) who were comparable to the H. pyloripositive group for age and sex. In addition all H. pyloripositive patients were examined before and after treatment aiming to eradicate H. pylori. In the H. pylori(+) patients the median PCNA index was 35 (range 8-58) and this was significantly higher than the respective number in the control group [5.5 (2 14), p<0.001]. In patients studied before and after successful eradication of H. pylori(n=10) the corresponding numbers were 35 (8-56) and 7 (4 13) (p<0.01) the latter not being significantly different from the control group of H. pylori(-)patients. On the contrary, in patients without successful H. pylori eradication (n=18) the PCNA indices before and after treatment were similar [35.5 (21-58) vs 31.5 (20-56)]. It is concluded that H. pyloriinfection alters the replication cycle of the gastric mucosa inducing hyperproliferation, which return towards normal after successful H. pylori eradication.

Serologic detection of CagA positive Helicobacter pylori strains predicts the presence of peptic ulcer in young dyspeptic patients.

BACKGROUND: Helicobacter Pylori infection has been strongly associated with upper gastrointestinal (GI) disease, especially duodenal ulcer. Endoscopy or contrast radiography is needed to diagnose and appropriately manage peptic ulcer disease. These diagnostic procedures, however, are time consuming and expensive; endoscopy is invasive and contrast radiography cannot help in the diagnosis of H pylori infection. Our aim was to examine in a prospective study the relation between serologic detection of cytotoxic associated gene (CagA) H pylori strains and endoscopic findings among young dyspeptic patients to determine whether this noninvasive test can help differentiate patients with from those without ulcers. METHODS: One hundred patients younger than 45 years with dyspepsia referred for upper GI endoscopy were included in the study. During endoscopy antral biopsy specimens were obtained for the rapid urease test and histologic examination. At histologic examination gastritis was graded from 0 (normal histologic features) to 3 (severe gastritis). After endoscopy blood was obtained for serologic determination of CagA status. RESULTS: Among the 100 patients 56 were H pylori positive and 44 were H pylori negative. In the group of 56 H pylori-positive patients 36 (64.3%) had peptic ulcers and 20 (35.7%) did not. Among patients with peptic ulcer 34 of 36 (94.4%) were CagA positive and 2 (5.6%) were CagA negative. The respective values for the group of patients without ulcers were 9 of 20 (45%) and 11 of 20 (55%). The difference in the proportion of CagA-positive subjects between the group with and that without peptic ulcer was highly significant (p < 0.0001). CONCLUSIONS: Among young patients with dyspepsia, CagA seropositivity is highly associated with duodenal ulcer at endoscopy.