Electronic Poster PresentationsElectronic Poster Round 1: Diagnosis of Helicobacter Infection

EP1.01 | “Test‐and‐treat” strategy with urea breath test: A cost‐effective approach for the management of Helicobacter pylori‐related dyspepsia and the prevention of peptic ulcer in the United Kingdom‐results of the Hp‐Breath initiative

D. M. Pritchard¹, J. Bornschein², I. L. P. Beales³, H. Salhi⁴, A. Beresniak⁵, P. Malfertheiner^6,7

¹Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom; ²Translational Gastroenterology Unit John Radcliffe Hospital Oxford University, Oxford, United Kingdom; ³Department of Gastroenterology, Norfolk and Norwich University Hospital, Norwich, United Kingdom; ⁴Mayoly Spindler Laboratories, Chatou, France; ⁵Data Mining International, Geneva, Switzerland; ⁶Department of Gastroenterology, Hepatology and Infectious Diseases, Otto‐von‐Guericke University Hospital, Magdeburg, Germany; ⁷Department of Medicine II, University Hospital, LMU, Munich, Germany

Background:

Clinical data comparing strategies used for the management of H. pylori‐associated diseases are limited. In the UK, Stool Antigen Test (SAT) seems to be the most frequently used non‐invasive test for H. pylori detection. Cost‐effectiveness studies might help to identify optimal strategies.

Aim:

To assess cost‐effectiveness of the “Test‐and‐Treat” strategy with Urea Breath Test (UBT) versus other strategies, in patients with H. pylori‐associated dyspepsia and peptic ulcer in the UK.

Methods:

Cost‐effectiveness models compared four strategies: “Test‐and‐Treat” including either UBT or SAT, “Endoscopy and Treat” and “Symptomatic Treatment”. Advanced simulations were performed over a 4 week time horizon for the endpoint “Probability of dyspepsia symptoms relief” and over 10 years for the “Probability of peptic ulcer avoided”. Models were developed according to UK routine medical practice and costs.

Results:

For the “Probability of dyspepsia symptoms relief” endpoint, “Test‐and‐Treat” strategies with either UBT or SAT were the most cost‐effective (respectively £459 and £452/success) versus “Endoscopy and Treat” and “Symptomatic Treatment” (respectively £1,115 and £897/success). For the “Probability of peptic ulcer avoided” endpoint, “Test‐and‐Treat” strategies with either UBT or SAT were also the most cost‐effective (respectively £182 and £167/peptic ulcer avoided/year) versus “Endoscopy and Treat” and “Symptomatic Treatment” (respectively £625 and £568/peptic ulcer avoided/year).

Conclusion:

“Test‐and‐Treat” strategies with either UBT or SAT are the most cost‐effective medical approaches for the management of H. pylori‐associated dyspepsia and the prevention of peptic ulcer in the UK. “Test‐and‐Treat” strategy with UBT has comparable cost‐effectiveness outcomes to the strategy utilising SAT.

D.M. Pritchard: F. Consultant/Advisory Board; Modest; Mayoly Spindler Laboratories. J. Bornschein: F. Consultant/Advisory Board; Modest; Mayoly Spindler Laboratories. I.L.P. Beales: F. Consultant/Advisory Board; Modest; Mayoly Spindler Laboratories. H. Salhi: A. Employment (full or part‐time); Modest; Mayoly Spindler Laboratories. A. Beresniak: F. Consultant/Advisory Board; Modest; Mayoly Spindler Laboratories. P. Malfertheiner: F. Consultant/Advisory Board; Modest; Mayoly Spindler Laboratories.

EP1.02 | Comparative estimation of results of the new selective rapid urease test and detection of H. pylori in stool: A pilot study

N. V. Baryshnikova^1,2, Y. P. Uspenskiy^1,3, A. N. Suvorov², M. A. Dmitrienko⁴

¹Pavlov First St‐Petersburg State Medical University, St‐Petersburg, Russian Federation; ²Institute of Experimental Medicine, St‐Petersburg, Russian Federation; ³Pediatric State St‐Petersburg Medical University, St‐Petersburg, Russian Federation; ⁴Association of Medicine and Analytic, St‐Petersburg, Russian Federation

Background:

According to Maastricht‐5, detection of H. pylori in stool is one of the main recommended method in clinical practice. Also we know many rapid urease tests for diagnosis of Helicobacter pylori (Hp) infection. It is fast, simple and cost‐effective methods but efficacy of them is different with some percent of false‐positive results. We begin to use the new selective rapid urease test for selective analysis of urease activity of H. pylori.

The Aim:

Comparative estimation of results of the new selective rapid urease test and detection of H. pylori in stool.

Materials and Methods:

We investigated gastric biopsies from antrum and fecal samples of eight patients to compare efficacy of the new selective rapid urease test (“Association of medicine and analytics, Saint‐Petersburg, Russia) and detection of H. pylori in stool by enzyme immunoassay. Patients during at least 4 weeks before diagnostics did not take any medications (PPIs, antibiotics, antacids and bismuth), which could change the results of both tests. Statistical processing was performed using the SPSS8.0 software package.

Results:

Concordance of results the new selective rapid urease test and detection of H. pylori in stool was 100%: 4 patient were H. pylori positive and 4 patient – H. pylori negative by results of both tests.

Conclusion:

The new selective rapid urease test shows the high concordance with results of detection of H. pylori in stool and can be recommended as express invasive test for diagnostic of H. pylori infection. Next studies are needed for further investigation of this test.

N.V. Baryshnikova: None. Y.P. Uspenskiy: None. A.N. Suvorov: None. M.A. Dmitrienko: None.

EP1.03 | Screening for Helicobacter pylori infection and Clarithromycin resistance using real‐time polymerase chain reaction

M. Kovacheva‐Slavova¹, H. Valkov¹, T. Angelov¹, R. Tropcheva², B. Vladimirov¹

¹Department of Gastroenterology, University Hospital Tsaritsa Ioanna‐ISUL, Medical University‐Sofia, Sofia, Bulgaria; ²Department of Biotechnology, Faculty of Biology, Sofia University “St. Kliment Ohridski”, Sofia, Bulgaria

Background:

Helicobacter pylori (H. pylori) infection is spread worldwide and affects at least half of the world's population. Infected people are at increased risk of several diseases development including gastric adenocarcinoma.

Aims:

The aim of this study was to screen patients with dyspeptic symptoms for H. pylori infection and assess Clarithromycin resistance prevalence among the infected patients.

Methods:

Screening for H. pylori infection was performed in all patients using molecular test based on real‐time polymerase chain reaction (RT‐PCR) in feces after RNA‐DNA extraction. Stool samples from all participants were collected 1‐3 days after patients’ hospitalization. The positive results were furthermore assessed for confirmation by breath test and stool antigen test. By point mutations detection in 23S rRNA gene was possible to detect Clarithromycin resistance. Statistical analysis was performed via SPSS 22.0.

Results:

This study enrolled 50 patients (18 males) at mean age 46.46 ± 15.10 years. Using molecular test based on RT‐PCR in feces we identified H. pylori infection in 24 patients (48.00%). Clarithromycin resistance was observed in 7 of them (29.17%). None of those patients was eradicated before. There was no significant difference by age and gender between infected and non‐infected patients. Gastrointestinal symptoms were more often reported in infected patients (P = 0.02). The molecular test showed 85.71% sensitivity and 100% specificity, with a diagnostic accuracy of 92.00%.

Conclusions:

H. pylori screening by molecular test based on RT‐PCR in feces might be beneficial as the test's accuracy is high and include Clarithromycin resistance assessment, which could improve the outcome of eradication therapy.

M. Kovacheva‐Slavova: None. H. Valkov: None. T. Angelov: None. R. Tropcheva: None. B. Vladimirov: None.

EP1.04 | Accuracy of the Helicobacter pylori diagnostic tests in patients with peptic ulcer bleeding‐ The results of a network meta‐analysis

N. Vörhendi, P. Hegyi, B. Erőss

Institute for Translational Medicine, Medical School, Pécs, Pécs, Hungary

Introduction:

Peptic ulcer (PU) being the most frequent source of gastrointestinal bleeding and Helicobacter pylori is a main etiologic factor for it. Some studies suggest accuracy of the diagnostic tests is decreased in PU bleeding. The international guidelines are vague on the method of testing in the setting of acute peptic ulcer bleeding. However, detection of H. pylori would be essential as it reduces the risks of untoward outcomes.

Aims:

Our aim was to update the most recent meta‐analysis which included studies until 2006 and to assess the accuracy of one or a combination of more diagnostic tests for H. pylori in patients with bleeding peptic ulcer.

Methods:

A comprehensive literature search was carried out from inception to November 2019 to perform a network meta‐analysis. We collected the raw data of diagnostic tests such as true positive, true negative, false positive and false negative values. All statistical calculations performed by R programming language using anova arm‐based model by Nyaga et al., 2018. We ranked the methods, index tests according to the diagnostic odds ratio and/or superiority index.

Results:

We analyzed 7 arbitrary gold standards in 7 network against single and combination of diagnostic tests. None of the calculated superiority indices proved that any of the tests have better diagnostic accuracy than the individual index tests.

Conclusion:

The results from are extensive network metaanalysis showed that none of the current diagnostic tests for H. plyori are better or worse in the diagnosis of the infection in the context of peptic ulcer bleeding.

N. Vörhendi: None. P. Hegyi: None. B. Erőss: None.

EP1.05 | Helicobacter pylori screening in patients with acute myocardial infarction

R. Hofmann, J. Wärme, M. Sundqvist, K. Mars, L. Aladellie, M. Bäck

Karolinska Institutet, Stockholm, Sweden

Introduction:

Potent antithrombotic therapy has significantly improved prognosis for patients with acute myocardial infarction (MI), however, at a price of increased bleeding risk. Chronic gastric infection with Helicobacter pylori (HP) commonly causes upper gastrointestinal bleeding and is proposed as a risk factor for MI. The prevalence of Hp in a current MI population and the feasibility of Hp screening as part of routine clinical care are unclear.

Aims & Methods:

In this multicenter, open‐label, clinical trial, all patients admitted for acute MI during the study period were eligible for enrollment. After written informed consent patients were tested for Hp infection with a bedside urea breath test (UBT [Mayoly Spindler]) incorporated into routine care during the hospitalization period.

Results:

274 consecutive MI patients (median age 67 years, 24% women) were enrolled. Overall, the HP prevalence was 20% (95% CI, 15.5‐25.3). The proportion of proton pump inhibitors (PPi) users was significantly higher in Hp negative compared to Hp positive patients (38% vs 16%; P = 0.003). After censoring of the 93 subjects with PPi exposure preceding the UBT, the HP prevalence was 25%. After adjusting for age and sex, smoking was found to be significantly associated with testing positive compared with negative for HP (33% vs 20%, P = 0.03).

Conclusion:

Hp is highly prevalent in a contemporary MI population. Hp screening in the setting of acute MI was found to be feasible. A future randomized trial is needed to determine if routine Hp screening and subsequent eradication therapy improves bleeding complications, cardiovascular outcomes, and ultimately, prognosis.

R. Hofmann: C. Other Research Support (supplies, equipment, receipt of drugs or other in‐kind support); Modest; Mayoly Spindler generously supported the diagnostics in this study, but had no role in the design of this study, data collection or interpretation of results. . J. Wärme: None. M. Sundqvist: None. K. Mars: None. L. Aladellie: None. M. Bäck: C. Other Research Support (supplies, equipment, receipt of drugs or other in‐kind support); Modest; Mayoly Spindler generously supported the diagnostics in this study, but had no role in the design of this study, data collection or interpretation of results..

EP1.06 | Diagnosis of Helicobacter pylori infection in the elderly by immunochromatographic assay‐based stool antigen test

Y. Han, W. Dai, F. Meng, X. Gan, M. Liu, X. Deng, Y. Li, G. Wang

Chinese PLA General Hospital, Beijing, China

Background:

The diagnostic role of Helicobacter pylori stool antigen (HpSA) test in elderly subjects remains unclear. The objective of this study was to assess the diagnostic accuracy of immunochromatographic assay‐based HpSA test in a male elderly cohort and to identify factors that may affect the accuracy.

Materials and Methods:

Data of asymptomatic elderly male citizens (≥65 years old) who conducted health check at Chinese PLA General Hospital between July 2007 and November 2018, were collected. Diagnostic accuracy of HpSA test was determined using ¹³C‐urea breath test as reference standard. Baseline comorbidities were analyzed for factors which were associated with the accuracy of HpSA test.

Results:

316 participants were enrolled, 193 in the pre‐treatment group (77.2 ± 7.8 years old) and 123 in the post‐treatment group (78.7 ± 8.3 years old). High accuracy (91.5%, 91.2% and 91.9%) and specificity (97.6%,98.7% and 96.0%) were obtained in all, pre‐ and post‐treatment groups respectively. However, the sensitivity was only 68.7%, 65.1% and 75.0%, respectively. In the pre‐treatment group, constipation was associated with decreased sensitivity (76.7% vs 38.5%, P = 0.039), while colorectal polyps with increased sensitivity (45.0% vs 82.6%, P = 0.010). Multivariate analysis indicated that constipation (OR = 0.115, 95% CI: 0.020‐0.666) and colorectal polyps (OR = 9.095, 95% CI: 1.656‐49.955) were independent factors for the sensitivity of HpSA in the pre‐treatment group.

Conclusions:

Immunochromatographic assay‐based HpSA test achieved high accuracy, with high specificity but suboptimal sensitivity in this elderly male cohort. Constipation was negatively while colorectal polyps was positively associated with HpSA sensitivity in pre‐treatment group.

Y. Han: None. W. Dai: None. F. Meng: None. X. Gan: None. M. Liu: None. X. Deng: None. Y. Li: None. G. Wang: None.

EP1.07 | Implementation of the program of the Scientific Society of Gastroenterologists of Russia “Physicians without helicobacteriosis” in Chita

E. Luzina¹, L. Lazebnik², N. Lareva¹, N. Chartorizhskaya¹, A. Dutova¹

¹Chita State Medical Academy, Chita, Russian Federation; ²Moscow State University of Medicine and Dentistry named after A. I. Evdokimov, Moscow, Russian Federation

Objective:

To identify the prevalence of Helicobacter pylori (HP) in doctors in Chita, morphological changes in gastric mucosa, carry out eradication treatment and assess its effectiveness, to determine HP resistance to clarithromycin.

Materials and Methods:

70 doctors were examined. НР antigen in feces was determined by immunochromatographic method before and 6‐8 weeks after the end of eradication treatment. In 27 biopsy specimens of the gastric mucosa HP DNA and mutations A2142G, A2143G, T2717C in the bacterial genome were determined. 29 biopsies of the stomach mucous membrane from 5 points for histological examination and evaluation by OLGA system were taken.

Results:

A positive result of AG HP in feces was recorded in 71.4% doctors. The efficiency of eradication treatment was 72.7% (table). During histological examination there was a high degree of inflammation in stomach mucosa, indicating high risk of erosive complications in the majority of doctors (86.1%). Different stages of atrophy were detected in 89.6%. Type III colonic metaplasia was detected in 6 (20.7%) people. One doctor demonstrated intraepithelial indefinite neoplasia. In 10 biopsies (37%) A2142G, A2143G mutations in the HP genome, ensuring its resistance to clarithromycin, were revealed. Mutations of T2717C were not determined.

Conclusion:

Doctors in Chita demonstrate a high level of HP infection, insufficient eradication treatment effectiveness, high level of genotypic HP resistance to clarithromycin, increased prevalence of precancerous changes in gastric mucosa.

E. Luzina: None. L. Lazebnik: None. N. Lareva: None. N. Chartorizhskaya: None. A. Dutova: None.

EP1.08 | “Helicobacter pylori and mast cells in the mucous membrane of the stomach”

N. Samodurova, D. Atiakshin

Voronezh State Medical University named after N. N. Burdenko, Voronezh, Russian Federation

Relevance:

Mast cells are able to regulate the state of the gastric mucosa using mediators with high activity. Despite the obvious pathogenetic role of mast cells in the development of gastritis induced by H. pylori (HP), the features of their functional and morphological co‐localization in the gastric mucosa are still poorly understood.

Materials and Methods of Research

The biopsy samples of the stomach of patients infected with H. pylori were studied, followed by analysis of the results of immunohistochemical staining.

Results:

The test material showed a high correlation between the abundance of mast cells and HP in the stomach mucosa. We noted frequent co‐localization of tryptase+‐mast cells with HP within paracrine influences the biological effects of specific proteases. Situations of direct contact of mast cells with HP cluster loci are particularly important. Activation of mast cell secretory pathways into a specific tissue gastric environment of patients infected with HP was also observed. An issue is also the resistance of the mucosa to HP in the presence of mast cells.

Conclusion:

The study is a step forward in understanding the mechanisms of HP infection progression. HP in the gastric mucosa leads to an increase in mast cell tryptase expression, increased inflammation and the development of biological effects of specific proteases.

N. Samodurova: None. D. Atiakshin: None.

EP1.09 | “Immunomorphological aspects of evaluating the interaction of mast cells and Helicobacter pylori in the stomach muсous”

N. Samodurova, D. Atiakshin

Voronezh State Medical University named after N. N. Burdenko, Voronezh, Russian Federation

Relevance:

Morphological identification of Helicobacter pylori (HP) in the gastric mucosa, including coccal forms of the spiral bacterium, helps to verify the diagnosis and refine the prognosis of the disease. The use of multiple immunomarking technology opens up new prospects for the informative value of histochemical analysis due to the possibility of simultaneous identification of HP and mast cells.

Materials and Methods:

Rabbit monoclonal antibodies (# ab172611, dilution 1:500) were used as primary antibodies for immunohistochemical staining of HP, and mast cell tryptases were murine monoclonal antibodies (# ab2378, dilution 1: 3000). Goat Anti‐Mouse IgG H&L antibodies (# ab97035) conjugated with Alexa Fluor 488 and Goat Anti‐Rabbit IgG H&L antibodies (# ab150077) conjugated with Cy3 were used as secondary antibodies in multiple immunomarking. Next, the nuclei were stained with DAPI (5 μg/mL PBS; Sigma) for 15 seconds, washed with PBS and the sections were enclosed in an anti‐fluorescent mounting medium. Stained micropreparations of the stomach were studied with a ZEISS Axio Imager.A2 microscope.

Results:

Localization of HP in the gastric mucosa led to an increase in the number of mast cells, their frequent colocalization with spiral bacteria, increased expression of tryptase and activation of its secretory pathways with the development of biological effects.

Conclusion:

Immunomorphological approaches provide new molecular aspects of the features of the interaction of mast cells and HP, expanding the interpretation of the mechanisms of the formation of a pro‐inflammatory background, the characteristics of immunogenesis and remodeling of the own plate of the gastric mucosa.

N. Samodurova: None. D. Atiakshin: None.