Diagnostic Accuracy of a Noninvasive Test for Detection of Helicobacter pylori and Resistance to Clarithromycin in Stool by the Amplidiag H. pylori+ClariR Real-Time PCR Assay

Recent advances in rapid detection of Helicobacter pylori by lateral flow assay

Infection with H. pylori (Helicobacter pylori) is the most prevalent human infection worldwide and is strongly associated with many gastrointestinal disorders, including gastric cancer. Endoscopy is mainly used to diagnose H. pylori infection in gastric biopsies. However, this approach is invasive, time-consuming and expensive. On the other hand, serology-based methods can be considered as a non-invasive approach to detecting H. pylori infection. The LFA (lateral flow assay) serves as a rapid point-of-care diagnostic tool. This paper-based platform facilitates the detection and quantification of analytes within human fluids such as blood, serum and urine. Due to ease of production, rapid results, and low costs, LFAs have a wide application in clinical laboratories and hospitals. In this comprehensive review, we examined LFA-based approaches for detection of H. pylori infection from human fluids and compare them with other high-sensitivity methods like ELISA (Enzyme-linked immunosorbent assay). Furthermore, we reviewed methods to elevate LFA sensitivity during H. pylori infection including, CRISPR/Cas system and isothermal amplification approaches. The development and optimization of novel labeling agents such as nanozyme to enhance the performance of LFA devices in detecting H. pylori were reviewed. These innovations aim to improve signal amplification and stability, thereby increasing the diagnostic accuracy of LFA devices. A combination of advances in LFA technology and molecular insight could significantly improve diagnostic accuracy, resulting in a significant improvement in clinical and remote diagnostic accuracy.

Accuracy of Fecal Polymerase Chain Reaction Testing in Clarithromycin-Resistant Helicobacter Pylori: A Systematic Review and Meta-Analysis

INTRODUCTION

The increasing prevalence of clarithromycin (CLA)-resistant Helicobacter pylori(H. pylori) strains poses a significant challenge in the management of H. pylori infections. This systematic review and meta-analysis investigates the diagnostic accuracy of polymerase chain reaction (PCR) in identifying CLA-resistant H. pylori strains in stool.

METHODS

A comprehensive literature search was conducted using PubMed, Embase, and Cochrane databases from database inception to April 30, 2023. Eligible studies evaluated the effectiveness of PCR stool tests in detecting CLA-resistant H. pylori strains in adults (>18-year-old). Studies of pediatric populations, alternative methods to PCR or stool samples, and reference tests other than gastric biopsy were excluded. The bivariate random-effects model was used to pool diagnostic accuracy from the included studies.

RESULTS

The analysis of 11 prospective diagnostic studies with a total of 866 patients showed a pooled sensitivity of 0.97 (95% CI: 0.9-0.99) and a pooled specificity of 0.98 (95% CI: 0.81-1.00). Subgroup analysis based on the used technique demonstrated consistent findings without notable variations. The diagnostic odds ratio was calculated at 1843.92 (95% CI: 134.28-25,321.3). The positive likelihood ratio was determined as 51.02 (95% CI: 4.61-564.5), while the negative likelihood ratio was found to be 0.03 (95% CI: 0.01-0.1).

DISCUSSION

PCR testing for clarithromycin-resistant H. pylori was highly sensitive and specific across studies with proven reliability in clinical practice, particularly in outpatient settings. Their implementation offers cost-effectiveness and the potential for tailored treatment strategies, holding promise for improved patient outcomes.

Clinical evaluation of a real-time PCR assay for diagnosis of Helicobacter pylori infection and antibiotic resistance

OBJECTIVES

Helicobacter pylori (H. pylori) is a globally prevalent bacterium that increases the risk of developing various gastrointestinal diseases, including gastric adenocarcinoma. This study aimed to evaluate the performances of real-time PCR assay in detecting H. pylori infection, as well as clarithromycin and levofloxacin resistance, in both stool and gastric biopsy specimens.

METHODS

Stool and gastric biopsy specimens were collected from patients within one to three days post-hospitalization. All patients were analyzed for H. pylori infection and resistance to clarithromycin and levofloxacin using a real-time PCR based molecular assay.

RESULTS

169 patients (83 males) with a mean age of 43.6±13.1 years were included in the study. The prevalence of H. pylori was 89.9% (152/169) in stool and 90.5% (153/169) in gastric biopsy samples. The molecular diagnostics employed in this study exhibited a sensitivity of 99.3% and a specificity of 100%, resulting in a diagnostic accuracy rate of 99.6%. Resistance to clarithromycin was 36.1% (61/169) in stool and 44.4% (75/169) in gastric biopsy samples. The molecular tests for clarithromycin resistance demonstrated a sensitivity of 96.8% and a specificity of 86.8%, with an overall diagnostic accuracy of 90.5%. Furthermore, resistance to levofloxacin was 22.5% (38/169) and 26.6% (45/169) in stool and gastric biopsy samples, respectively. The molecular test demonstrated a sensitivity of 80.9% and a specificity of 94.3%, resulting in a diagnostic accuracy of 90.5%.

CONCLUSION

The implementation of real-time PCR-based screening for H. pylori infection and resistance to clarithromycin and levofloxacin in the stool may enhance the success rate of eradication therapy.

Real-World Situation of Eradication Regimens and Risk Factors for Helicobacter pylori Treatment in China: A Retrospective Single-Center Study

Background and Objectives

The success rate of Helicobacter pylori (H. pylori) eradication in China is declining. The aim of this study was to evaluate eradication outcomes in clinical practice and identifies factors contributing to treatment failure.

Methods

A retrospective review was conducted on patients treated for H. pylori infection with 14-day bismuth-containing quadruple therapy at a Beijing medical center from January 2020 to December 2023. We analyzed demographic and clinical data, eradication rates across regimens, and performed multivariate analysis to pinpoint predictors of failure.

Results

Out of 3340 participants, 2273 (68.1%) achieved eradication. Amoxicillin-based combinations (69.2%) outperformed other antibiotic regimens (58.9%, p < 0.001), with amoxicillin plus doxycycline reaching a 71.4% success rate. Esomeprazole-based regimens were more effective (73.6%) than other PPI regimens (65.2%, p = 0.001), notably, a rabeprazole, amoxicillin, doxycycline, and bismuth combination had an 80.0% success rate. Age, gender, and smoking and drinking were significant eradication failure predictors.

Conclusion

In real-world settings, 14-day amoxicillin and esomeprazole-based quadruple regimens have been demonstrated to be more effective than other regimens. Age, gender, and lifestyle habits are identified as independent risk factors for eradication failure.

Registration

This study was registered in the Chinese Clinical Trial Registry on 08/01/2024 (clinical trial registration number: ChiCTR2400079647).

An altered uterine microbiota with endometrial hyperplasia

BACKGROUND

Endometrial hyperplasia (EH) is a precursor to endometrial cancer, and the role of the microbiome in its development is unclear.

RESULTS

The present study investigated the uterine microbiome in patients with benign uterine conditions and endometrial hyperplasia. A significant structural shift in the uterine microbiome of patients with endometrial hyperplasia compared to those with benign conditions was found. Delftia, Serratia and Stenotrophomonas were significantly enriched in endometrial hyperplasia samples and associated with the presence of endometrial hyperplasia.

CONCLUSIONS

The novel finding suggested that increased abundance of Delftia, Serratia and Stenotrophomonas is associated with the presence of endometrial hyperplasia. Further investigation is needed to determine the value of these microbes as biomarkers for endometrial hyperplasia.

Obesity, abdominal obesity, metabolic obesity phenotypes, and Helicobacter pylori infection: results from NHANES 1999-2000

BACKGROUND

Recent studies on the association between Helicobacter pylori (H. pylori) infection and obesity have reported conflicting results. Therefore, the purpose of our study was to investigate the association of obesity, abdominal obesity, and metabolic obesity phenotypes with H. pylori infection.

METHODS

A cross-sectional study of 1568 participants aged 20 to 85 was conducted using the National Health and Nutrition Examination Survey (NHANES) cycle 1999-2000. Logistic regression models were employed to evaluate the association of general obesity as defined by body mass index (BMI), abdominal obesity as defined by waist circumference (WC) and waist-height ratio (WHtR), and metabolic obesity phenotypes with H. pylori seropositivity. Subgroup analyses stratified by age were conducted to explore age-specific differences in this association.

RESULTS

After grouping individuals according to their WHtR, the prevalence rate of WHtR ≥ 0.5 in H. pylori-seropositive participants was significantly higher than that in H. pylori-seronegative participants (79.75 vs. 68.39, P < 0.001). The prevalence of H. pylori seropositivity in non-abdominal obesity and abdominal obesity defined by WHtR was 24.97% and 31.80%, respectively (P < 0.001). In the subgroup analysis, the adjusted association between abdominal obesity, as defined by the WHtR, and H. pylori seropositivity was significant in subjects aged < 50 years (OR = 2.23; 95% CI, 1.24-4.01; P = 0.01) but not in subjects aged ≥ 50 years (OR = 0.84; 95% CI, 0.35-1.99; P = 0.66). Subjects older than 50 years old had an OR (95% CI) for metabolically healthy obesity of 0.04 (0.01-0.35) compared with the control group. H. pylori seropositivity was consistently not associated with obesity as defined by BMI.

CONCLUSIONS

Abdominal obesity, as defined by the WHtR, was associated with H. pylori infection in subjects aged ≤ 50 years.

Role of MIC levels and 23S rRNA mutation sites to clarithromycin in 14-day clarithromycin bismuth quadruple therapy for Helicobacter pylori eradication: A prospective trial in Beijing

Background

Rising clarithromycin resistance undermines Helicobacter pylori (H. pylori) treatment efficacy. We aimed to determine clarithromycin's minimum inhibitory concentration (MIC) levels and identify specific mutation sites in the 23S ribosomal subunit (23S rRNA) that predict treatment outcomes in a 14-day regimen of clarithromycin bismuth quadruple therapy (amoxicillin 1g, clarithromycin 500 mg, rabeprazole 10 mg, and colloidal bismuth pectin 200 mg).

Materials and methods

We included adult H. pylori patients who hadn't previously undergone clarithromycin-based treatment, either as initial or rescue therapy. Exclusions were made for penicillin allergy, recent use of related medications, severe illnesses, or inability to cooperate. Patients underwent a 14-day clarithromycin bismuth quadruple therapy. Gastric mucosa specimens were obtained during endoscopy before eradication. MIC against amoxicillin and clarithromycin was determined using the E-test method. The receiver operating characteristic (ROC) curve helped to find the optimal clarithromycin resistance MIC breakpoint. Genetic sequences of H. pylori 23S rRNA were identified through Sanger Sequencing. (ChiCTR2200061476).

Results

Out of 196 patients recruited, 92 met the inclusion criteria for the per-protocol (PP) population. The overall intention-to-treat (ITT) eradication rate was 80.00 % (84/105), while the modified intention-to-treat (MITT) and PP eradication rates were 90.32 % (84/93) and 91.30 % (84/92) respectively. No amoxicillin resistance was observed, but clarithromycin resistance rates were 36.19 % (38/105), 35.48 % (33/93), and 34.78 % (33/92) in the ITT, MITT, and PP populations respectively. Compared with the traditional clarithromycin resistance breakpoint of 0.25 μg/mL, a MIC threshold of 12 μg/mL predicted better eradication. Among 173 mutations on 152 sites in the 23S rRNA gene, only the 2143A > G mutation could predict eradication outcomes (p < 0.000).

Conclusions

Interpretation of elevated MIC values is crucial in susceptibility testing, rather than a binary "susceptible" or "resistant" classification. The 2143A > G mutation has limited specificity in predicting eradication outcomes, necessitating further investigation into additional mutation sites associated with clarithromycin resistance.

Testing for Helicobacter pylori in an era of antimicrobial resistance

Antimicrobial resistance in Helicobacter pylori has reached alarming levels and is compromising traditional empiric treatment of H. pylori. Antimicrobial susceptibility testing is routinely performed for infectious diseases when there is a risk of resistance and is now recommended to guide therapy for H. pylori. This mini-review overviews the current diagnostics for H. pylori with a focus on tests that enable susceptibility-guided treatment, including molecular tests performed directly on stool and endoscopically collected specimens.

Graded diagnosis of Helicobacter pylori infection using hyperspectral images of gastric juice

Helicobacter pylori is a potential underlying cause of many diseases. Although the Carbon 13 breath test is considered the gold standard for detection, it is high cost and low public accessibility in certain areas limit its widespread use. In this study, we sought to use machine learning and deep learning algorithm models to classify and diagnose H. pylori infection status. We used hyperspectral imaging system to gather gastric juice images and then retrieved spectral feature information between 400 and 1000 nm. Two different data processing methods were employed, resulting in the establishment of one-dimensional (1D) and two-dimensional (2D) datasets. In the binary classification task, the random forest model achieved a prediction accuracy of 83.27% when learning features from 1D data, with a specificity of 84.56% and a sensitivity of 92.31%. In the ternary classification task, the ResNet model learned from 2D data and achieved a classification accuracy of 91.48%.

High incidence of antibiotic resistance amongst isolates of Helicobacter pylori collected in Nottingham, UK, between 2001 and 2018

Introduction. Helicobacter pylori is the leading cause of peptic ulcers and gastric cancer. The most common treatment regimens use combinations of two or three antibiotics and a proton pump inhibitor (PPI) to suppress stomach acid. The World Health Organization designated clarithromycin-resistant H. pylori as a high priority pathogen for drug development, due to increasing antibiotic resistance globally.Hypothesis/Gap Statement. There is no routine surveillance of H. pylori primary antimicrobial sensitivities in the UK, and published data are lacking.Aim. This study aimed to characterize antimicrobial sensitivities of isolates collected in Nottingham, UK, between 2001 and 2018.Methodology. Gastric biopsy samples were collected, with informed written consent and ethics approval, from 162 patients attending the Queen's Medical Centre in Nottingham for an upper GI tract endoscopy. Antibiotic sensitivity was assessed using E-Tests and a more cost-effective disc diffusion test.Results. The clarithromycin, amoxicillin and levofloxacin disc diffusion tests provided identical results to E-Tests on a subset of 30 isolates. Disparities were observed in the metronidazole test results, however. In total, 241 isolates from 162 patients were tested using at least one method. Of all isolates, 28 % were resistant to clarithromycin, 62 % to metronidazole and 3 % to amoxicillin, which are used in first-line therapies. For those antibiotics used in second- and third-line therapies, 4 % were resistant to levofloxacin and none of the isolates were resistant to tetracycline. Resistance to more than one antibiotic was found in 27 % of isolates. The frequency of patients with a clarithromycin-resistant strain increased dramatically over time: from 16 % between 2001 and 2005 to 40 % between 2011 and 2018 (P=0.011). For the same time periods, there was also an increase in those with a metronidazole-resistant strain (from 58 to 78 %; P=0.05). The frequencies of clarithromycin and metronidazole resistance were higher in isolates from patients who had previously received eradication therapy, compared to those who had not (40 % versus 77 %, and 80 % versus 92 %, respectively). Of 79 pairs of isolates from the antrum and corpus regions of the same patient's stomach, only six had differences in their antimicrobial susceptibility profiles.Conclusion. Although there was high and increasing resistance to clarithromycin and metronidazole, there was no resistance to tetracycline and the frequencies of amoxicillin and levofloxacin resistance were very low.

Advances on diagnosis of Helicobacter pylori infections

The association of Helicobacter pylori to several gastric diseases, such as chronic gastritis, peptic ulcer disease, and gastric cancer, and its high prevalence worldwide, raised the necessity to use methods for a proper and fast diagnosis and monitoring the pathogen eradication. Available diagnostic methods can be classified as invasive or non-invasive, and the selection of the best relies on the clinical condition of the patient, as well as on the sensitivity, specificity, and accessibility of the diagnostic test. This review summarises all diagnostic methods currently available, including the invasive methods: endoscopy, histology, culture, and molecular methods, and the rapid urease test (RUT), as well as the non-invasive methods urea breath test (UBT), serological assays, biosensors, and microfluidic devices and the stool antigen test (SAT). Moreover, it lists the diagnostic advantages and limitations, as well as the main advances for each methodology. In the end, research on the development of new diagnostic methods, such as bacteriophage-based H. pylori diagnostic tools, is also discussed.

Diagnostic accuracy of stool sample-based PCR in detecting Helicobacter pylori infection: a meta-analysis

The present study was to evaluate the diagnostic accuracy of different types of PCR tests with the aim of determining which one performs best for detecting Helicobacter pylori in stool samples. Related articles were searched from PubMed, Embase, Web of Science databases, Scopus, and Scholar Google. The quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool and RevMan5.4 software. Pooled sensitivity, specificity, DOR, PLR and NLR for the stool PCR test in detecting H. pylori infection were performed by Stata 15.0 software. Subgroup meta-analysis was performed by Open Meta-analyst software. Ten studies were selected in this study. Stool PCR test had 92.0 % (83.0, 96.0 %) pooled sensitivity, 96.0 % (84.0, 99.0 %) pooled specificity, 296.0 (51.6, 1,696.9) pooled DOR, 26.1 (5.3, 128.7) pooled PLR and 0.09 (0.04, 0.18) NLR in the diagnosis of H. pylori infection, and summary receiver operating characteristic curve (SROC) illustrated an area under the curve (AUC) of 0.98. Subgroup meta-analysis showed rtPCR as having the highest diagnostic accuracy. Our results identify rtPCR as having the highest diagnostic accuracy for the detection of H. pylori in stool samples, and the stool PCR test as a reliable diagnostic tool for H. pylori infection.

Updates to the Diagnosis and Clinical Management of Helicobacter pylori Infections

BACKGROUND

Helicobacter pylori (H. pylori) affects nearly half of the world's populations with high incidence and prevalence rates in developing countries. Infection with H. pylori increases the risk of developing peptic ulcer disease and gastric cancer. This review provides a summary of the prevalence and microbiology of H. pylori with emphasis on the current diagnostic methods and clinical management strategies.

CONTENT

This review discusses current options and developments in H. pylori diagnosis with the challenges and advantages associated with both noninvasive and invasive methods. The advantages of molecular methods for the diagnosis of H. pylori infection and prediction of clarithromycin resistance directly from stool or tissue biopsies are discussed. In addition, we provide a brief review on the treatment for H. pylori indicated in patients with evidence of active infection with the organism's antimicrobial resistance patterns taken into consideration.

SUMMARY

Testing for H. pylori has largely centered around fecal antigen testing, urea breath testing, and immunohistochemical staining from tissue biopsies. Culture-based diagnostics followed by phenotypic antimicrobial susceptibility testing is the gold standard for detection of resistance patterns. Due to the fastidious nature of the organism, culture methods are time consuming and labor intensive. Rapid nucleic acid amplification tests for H. pylori identification from direct specimens and molecular determination of drug resistance markers are accurate alternatives for H. pylori diagnosis but are not widely adopted. H. pylori antimicrobial resistance rates are on the rise due to the widespread use of antibiotics. Antibiotic regimens including the quadruple therapy and non-clarithromycin triple therapies have a higher success rate, with newer vonoprazon-based regimens showing promising eradication rates.

Approaches for detection of antibiotic resistance of Helicobacter pylori: Recent research advances

Helicobacter pylori (H. pylori) infection, a contagious disease, has affected approximately half of the global population. It is associated with the occurrence and development of many diseases, which seriously endangers human public health. Antibiotics play an important role in H. pylori eradication therapy, and the common regimens for H. pylori eradication contain one to three antibiotics. Antibiotic resistance is one of the main reasons for the failure of H. pylori eradication. Detection of antibiotic resistance can be helpful for individualized management, reduction of drug resistance, and improvement of H. pylori eradication. Methods to detect antibiotic resistance of H. pylori primarily consist of traditional drug sensitivity tests and molecular biology methods, such as polymerase chain reaction and its related techniques, DNA sequencing, fluorescence in situ hybridization, and gene chip. This paper reviews the recent advances in approaches for detection of antibiotic resistance of H. pylori.

Efficacy of quadruple therapy with clarithromycin based on faecal molecular antimicrobial susceptibility tests as first-line treatment for Helicobacter pylori infection: a protocol of a single-centre, single-blind, randomised clinical trial in China

INTRODUCTION

Helicobacter pylori is the most well-known risk factor for gastric cancer. Antibiotic resistance is the main reason for the failure of H. pylori eradication, and understanding the antibiotic resistance before treatment may be the main determinant of successful eradication of H. pylori. This study aims to evaluate the efficacy and safety of quadruple therapy based on faecal molecular antimicrobial susceptibility tests for the first-line eradication of H. pylori infection.

METHODS AND ANALYSIS

This is a single-centre, single-blind, randomised controlled trial, enrolling 855 patients with H. pylori infection. Patients are randomised to three groups for a 14-day treatment: group A: amoxicillin- and clarithromycin-based bismuth-containing quadruple therapy (BQT) (rabeprazole 10 mg, amoxicillin 1 g, clarithromycin 500 mg and colloidal bismuth 200 mg two times per day); group B: clarithromycin medication history-based BQT (rabeprazole 10 mg, amoxicillin 1 g, furazolidone 100 mg (with clarithromycin medication history)/clarithromycin 500 mg (without clarithromycin medication history) and colloidal bismuth 200 mg two times per day); group C: antimicrobial susceptibility test-based BQT (rabeprazole 10 mg, amoxicillin 1 g, clarithromycin 500 mg (clarithromycin-sensitive)/furazolidone 100 mg (clarithromycin resistant) and colloidal bismuth 200 mg two times per day). The primary end point is the eradication rate. The secondary end points are the incidence of adverse events and compliance.

ETHICS AND DISSEMINATION

This study was approved by the Ethics Committee of Second Affiliated Hospital, School of Medicine, Zhejiang University (Number 20230103). The results will be published in the appropriate peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT05718609.

Raman Spectroscopy for Urea Breath Test

The urea breath test is a non-invasive diagnostic method for Helicobacter pylori infections, which relies on the change in the proportion of 13CO2 in exhaled air. Nondispersive infrared sensors are commonly used for the urea breath test in laboratory equipment, but Raman spectroscopy demonstrated potential for more accurate measurements. The accuracy of the Helicobacter pylori detection via the urea breath test using 13CO2 as a biomarker is affected by measurement errors, including equipment error and δ13C measurement uncertainty. We present a Raman scattering-based gas analyzer capable of δ13C measurements in exhaled air. The technical details of the various measurement conditions have been discussed. Standard gas samples were measured. 12CO2 and 13CO2 calibration coefficients were determined. The Raman spectrum of the exhaled air was measured and the δ13C change (in the process of the urea breath test) was calculated. The total error measured was 6% and does not exceed the limit of 10% that was analytically calculated.

Individualized diagnosis and eradication therapy for Helicobacter pylori infection based on gene detection of clarithromycin resistance in stool specimens: A systematic review and meta-analysis

BACKGROUND

Empiric therapy for Helicobacter pylori infection results in significantly increased antibiotic resistance and decreased eradication efficacy. The genotypic testing of clarithromycin resistance from stool specimens is a promising method for individualized diagnosis and treatment. This study aimed to determine the status of research and application on this method through a systematic review and meta-analysis.

METHODS

PubMed, Embase, MEDLINE, and WAN FANG database were searched for relevant literature. The quality of included diagnostic articles was evaluated using the quality Assessment of Diagnostic Accuracy Studies-2 tool. A bivariate random-effect model was conducted to calculate the diagnostic accuracy of genotypic testing of clarithromycin resistance.

RESULTS

A total of 16 diagnostic-related were included and analyzed after exclusions. The pooled sensitivity and specificity of diagnostic meta-analysis were 0.93 (95% confidence interval [CI]: 0.90-0.96) and 0.98 (95% CI: 0.93-1.00), respectively. The area under the curve (AUC) of the summary receiver operating characteristic was 0.97 (95% CI: 0.95-0.98). The genotypic testing in stool samples had heterogeneous sensitivity (Q = 37.82, p < .01, I²  = 37.82) and specificity (Q = 60.34, p < .01, I²  = 93.72) in detecting clarithromycin resistance. Purification method, stool sample weight, real-time PCR, and antimicrobial susceptibility testing as reference accounted for the heterogeneity of pooled sensitivity, while patient age, purification method, stool sample weight, and real-time PCR for the heterogeneity of pooled specificity.

CONCLUSION

The genotypic testing of clarithromycin resistance from stool specimens is an accurate, convenient, noninvasive, and rapid detection technology, providing a definitive diagnosis of clarithromycin resistance and guiding the rational antibiotic selection.

The State of the Art of Molecular Fecal Investigations for Helicobacter pylori (H. pylori) Antibiotic Resistances

A new paradigm shift for the treatment of Helicobacter pylori (H. pylori) infection would be timely due to a progressive increase in antibiotic resistance. Such a shift in the perspective of the H. pylori approach should include the preliminary assessment of antibiotic resistance. However, the availability of sensitivity tests is not widespread and the guidelines have always indicated empirical treatments without taking into account the need to make sensitivity tests accessible, i.e., the necessary starting point for improving results in different geographical areas. Currently, the traditional tools for this purpose (culture) are based on performing an invasive investigation (endoscopy) and often involve technical difficulties; thus, they were only confined to the settings where multiple attempts at eradication have failed. In contrast, genotypic resistance testing of fecal samples using molecular biology methods is much less invasive and more acceptable to patients. The purpose of this review is to update the state of the art of molecular fecal susceptibility testing for the management of this infection and to extensively discuss the potential benefits of their large-scale deployment, i.e., novel pharmacological opportunities.

Helicobacter pylori World Gastroenterology Organization Global Guideline

Helicobacter pylori remains a major health problem worldwide, causing considerable morbidity and mortality due to peptic ulcer disease and gastric cancer. The burden of disease falls disproportionally on less well-resourced populations. As with most infectious diseases, the largest impact on reducing this burden comes from improvement in socioeconomic status, which interrupts transmission. This has been observed in many regions of the world, but the prevalence of infection remains high in many regions where improvements in living standards are slow to occur. Meanwhile, the optimal clinical management and treatment pathways remain unsettled and are evolving with changing antimicrobial resistance patterns. Despite decades of research and clinical practice, major challenges remain. The quest for the most effective, safe, and simple therapy remains the major issue for clinicians. The search for an effective vaccine appears to be elusive still. Clinical guidelines do not infrequently proffer discordant advice. A major challenge for guidelines is for relevance across a variety of populations with a varying spectrum of disease, antimicrobial resistance rates, and vastly different resources. As local factors are central to determining the impact and management strategies for H. pylori infection, it is important that pathways are based on the best available local knowledge rather than solely extrapolating from guidelines formulated in other regions, which may be less applicable. To this end, this revision of the World Gastroenterology Organisation (WGO) H. pylori guideline uses a "Cascades" approach that seeks to summarize the principles of management and offer advice for pragmatic, relevant and achievable diagnostic and treatment pathways based on established key treatment principles and using local knowledge and available resources to guide regional practice.

Diagnostic and Therapeutic Management of Helicobacter pylori Infection in Primary Care: Perspective of Application in France and Narrative Review of the Literature

BACKGROUND

Helicobacter pylori (Hp) infection affects 30% to 40% of people in industrialized countries.

AIM

This study aimed to synthesize knowledge on the diagnostic and therapeutic management of Hp infection in general practice in people under 40 years of age.

METHOD

A narrative review of the literature with an inductive content analysis of the articles was performed.

RESULTS

The extracted data (22 articles out of 106 included after screening of 965 articles) determined three areas of analysis: indications for screening, methods of screening and diagnosis by non-invasive tests, and treatment modalities.

DISCUSSION

Targeted, easily performed screening with noninvasive tests is recommended for patients younger than 45 years of age with no family history of gastric cancer and symptoms of dyspepsia without warning signs. Given their proximity to the general population and their coverage of the territory, general practitioners are ideally positioned. Treatment modalities are well-codified and feasible in primary care. Simplifying the recommendations available to them would optimize the identification of patients at risk and the management of Hp infection. Informing, educating, involving, supporting, and promoting the control of Hp infection in primary care will be future goals. Further research is needed in primary care to evaluate the impact of new procedures on Hp control.

Helicobacter pylori Infection: Current Status and Future Prospects on Diagnostic, Therapeutic and Control Challenges

Helicobacter pylori (H. pylori) infection, which affects approximately half of the world's population, remains a serious public health problem. As H. pylori infection leads to a number of gastric pathologies, including inflammation, gastroduodenal ulcers, and malignancies, early detection and treatment are crucial to preventing the spread of the infection. Multiple extragastric complications, such as iron deficiency anaemia, immune thrombocytopenic purpura, vitamin B12 deficiency, diabetes mellitus, cardiovascular diseases, and certain neurological disorders, have also been linked to H. pylori infection. An awareness of H. pylori and associated health hazards is necessary to minimize or even eradicate the infection. Therefore, there is an urgent need to raise the standards for the currently employed diagnostic, eradication, alternative treatment strategies. In addition, a brief overview of traditional and cutting-edge approaches that have proven effective in identifying and managing H. pylori is needed. Based on the test and laboratory equipment available and patient clinical characteristics, the optimal diagnostic approach requires weighing several factors. The pathophysiology and pathogenic mechanisms of H. pylori should also be studied, focusing more on the infection-causing virulence factors of this bacterium. Accordingly, this review aims to demonstrate the various diagnostic, pathophysiological, therapeutic, and eradication tactics available for H. pylori, emphasizing both their advantages and disadvantages. Invasive methods (such as quick urease testing, biopsy, or culture) or noninvasive methods (such as breath tests, stool investigations, or serological tests) can be used. We also present the most recent worldwide recommendations along with scientific evidence for treating H. pylori. In addition to the current antibiotic regimens, alternative therapies may also be considered. It is imperative to eradicate the infections caused by H. pylori as soon as possible to prevent problems and the development of stomach cancer. In conclusion, significant advances have been made in identifying and treating H. pylori. To improve eradication rates, peptide mass fingerprinting can be used as a diagnostic tool, and vaccines can also eliminate the infection.

Usefulness of Molecular Methods for Helicobacter pylori Detection in Pediatric Patients and Their Correlation with Histopathological Sydney Classification

Helicobacter pylori infections, as one of the most prevalent among humans, are generally acquired during childhood, and are one of the main causes of chronic gastritis and peptic ulcer disease. A bacterial culture from a gastric biopsy is the gold standard and is the only method that has 100% specificity. However, its sensitivity varies, depending on experience of the laboratory staff, applied culture media, specimen transport conditions, biopsy site, and quality of the sample. The same factors compromise all invasive methods and a culture-based H. pylori infection diagnostic, as well as a recent intake of antibiotics, bismuth-containing compounds, and proton pump inhibitors. Molecular methods have been used for clinical microbiology investigation since the beginning of the 21st century. However, their usefulness for H. pylori infections diagnosis remains unclear, especially in pediatric patients. The aim of the study was to assess the incidence of H. pylori infections in a group of 104 pediatric patients and to compare the results of the PCR test with the corresponding histopathological investigation effects. Among the biopsy samples collected from 104 children, 44 (42.3%) were positive in PCR, while 43 (41.3%) and 39 (37.5%) presented histologically-confirmed signs of inflammation and H. pylori colonization, respectively. Moreover, the mean grades of the parameters of the histopathological examination were higher in the group of PCR-positive samples. The compatibility of both research methods was confirmed, emphasizing the usefulness of molecular methods for detecting H. pylori infections in pediatric patients. Considering that the PCR-based method gives reliable results and is less time-consuming and costly, it is worth discussing this method as a new standard in the diagnosis of H. pylori infections, at least among pediatric patients, for which culture-based diagnostics is not sufficient or histopathological examination is negative, while inflammation signs are observed macroscopically.

Evaluation of a Molecular Mosprie Assay for Detection of Helicobacter pylori and Resistance to Clarithromycin and Levofloxacin

BACKGROUND

Helicobacter pylori eradication regimens should be guided by antimicrobial susceptibility testing. The objective of this study was to evaluate the molecular-based Mosprie assay for detecting H. pylori resistance to clarithromycin and levofloxacin using gastric biopsies.

METHODS

A total of 185 culture-positive frozen gastric biopsies were included for Mosprie assay and also for 23S rRNA and gyrA gene sequencing. The susceptibility results by the Mosprie assay were compared with the E-test results retrospectively retrieved. The discordant results were analyzed by sequencing of the 23S rRNA and gyrA genes.

RESULTS

Susceptibility concordance between the Mosprie assay and E-test for clarithromycin and levofloxacin was 97.30% (180/185) and 88.11% (163/185), respectively. The full agreement between clarithromycin genotypes by Mosprie assay and the 23S rRNA sequencing results was observed in the 5 samples with discordant Mosprie assay and E-test results. However, for levofloxacin, of the 16 discordant samples with resistant phenotype but a susceptible genotype by Mosprie assay, 6 were found to have levofloxacin resistance-related gyrA gene mutations.

CONCLUSIONS

The rapid and reliable Mosprie assay can be recommended for H. pylori susceptibility testing of clarithromycin and levofloxacin on gastric biopsies. Future technical improvements are needed in detecting levofloxacin resistance-associated gene mutations.

Effect of metronidazole resistance on Helicobacter pylori eradication regimens

OBJECTIVES

Guidelines suggest bismuth-containing quadruple therapy (BQT) or concomitant therapy (CT) as first-line therapy in our geographic area. Both schedules contain metronidazole. We aimed to evaluate the effect of metronidazole resistance to Helicobacter pylori (H. pylori) eradication therapy.

METHODS

We recruited treatment-naïve subjects with H. pylori infection who received either CT or BQT during January 2020 and December 2021. Before therapy, a fecal sample was collected using the THD fecal test device from each patient. H. pylori DNA was extracted and mutations of rdxA and frxA genes and A2143G for metronidazole and clarithromycin resistance were investigated using real-time polymerase chain reaction with a high-resolution melting curve.

RESULTS

Ninety-six patients were enrolled, including 29 received BQT and 67 received CT. The overall eradication rate was 94.8% (100% for BQT and 92.5% for CT). Metronidazole resistance was found in 18 (18.8%) subjects, while clarithromycin resistance was found in 19 (19.8%). All 18 patients with metronidazole resistance achieved successful eradication (five treated with BQT and 13 with CT). The eradication rate in metronidazole-sensitive strains was 93.6%. Of these, 24 received BQT with 100% success, and 54 had CT with five failures (successful eradication in 90.7%). Two patients with treatment failure were resistant to clarithromycin, and the remaining three were susceptible to both clarithromycin and metronidazole. No statistical significance was observed in the eradication rate between metronidazole-resistant and -sensitive strains (100% vs 93.6%, P = 0.58).

CONCLUSION

Metronidazole resistance does not influence the eradication rate of BQT and CT regimens in our geographical area, even if such results need to confirmed in a larger sample.

Helicobacter pylori Infection, Its Laboratory Diagnosis, and Antimicrobial Resistance: a Perspective of Clinical Relevance

Despite the recent decrease in overall prevalence of Helicobacter pylori infection, morbidity and mortality rates associated with gastric cancer remain high. The antimicrobial resistance developments and treatment failure are fueling the global burden of H. pylori-associated gastric complications. Accurate diagnosis remains the opening move for treatment and eradication of infections caused by microorganisms. Although several reports have been published on diagnostic approaches for H. pylori infection, most lack the data regarding diagnosis from a clinical perspective. Therefore, we provide an intensive, comprehensive, and updated description of the currently available diagnostic methods that can help clinicians, infection diagnosis professionals, and H. pylori researchers working on infection epidemiology to broaden their understanding and to select appropriate diagnostic methods. We also emphasize appropriate diagnostic approaches based on clinical settings (either clinical diagnosis or mass screening), patient factors (either age or other predisposing factors), and clinical factors (either upper gastrointestinal bleeding or partial gastrectomy) and appropriate methods to be considered for evaluating eradication efficacy. Furthermore, to cope with the increasing trend of antimicrobial resistance, a better understanding of its emergence and current diagnostic approaches for resistance detection remain inevitable.

Current and Future Perspectives in the Diagnosis and Management of Helicobacter pylori Infection

Helicobacter pylori (Hp) is a prevalent organism infecting almost half the global population. It is a significant concern, given its associated risk of gastric cancer, which is the third leading cause of cancer death globally. Infection can be asymptomatic or present with dyspeptic symptoms. It may also present with alarm symptoms in the case of progression to cancer. Diagnosis can be achieved non-invasively (breath tests, stool studies, or serology) or invasively (rapid urease test, biopsy, or culture). Treatment involves acid suppression and regimens containing several antibiotics and is guided by resistance rates. Eradication is essential, as it lowers the risk of complications and progression to cancer. Follow-up after eradication is similarly important, as the risk of cancer progression remains. There have been many recent advances in both diagnosis and treatment of Hp. In particular, biosensors may be effective diagnostic tools, and nanotechnology, vaccines, and potassium-competitive acid blockers may prove effective in enhancing eradication rates.

Prevalence of Helicobacter pylori resistance to clarithromycin in Tunisia

Background. Helicobacter pylori (H. pylori) resistance to clarithromycin is increasing worldwide. Data on the prevalence of H. pylori resistance are limited in Tunisia.Gap statement. Given that H. pylori resistance to clarithromycin has not been studied in Tunisia since 2010, there was a need to determinate its prevalence and the principal mutations implicated in this resistance.Aim. The aims were to define the prevalence of H. pylori infection among symptomatic patients and to determinate the level of clarithromycin resistance among these patients and the main mutations conferring this resistance.Methods. We conducted a cross-sectional study from March 2017 to February 2020 in the Hepato-Gastroenterology Department of Hedi Chaker University Hospital in Sfax that included 124 Tunisian patients who underwent gastroduodenal endoscopy with biopsies. Mutations conferring resistance to clarithromycin were detected using the Allplex H. pylori and ClariR PCR Assay.Results. Out of 124 biopsies, 101 (81.5 2 %) were PCR-positive for H. pylori. Mutations conferring resistance to clarithromycin were detected in 30/95 (31.6 %) of patients. The rate of primary resistance was 25.3 % and of secondary resistance 62.5 %. The most frequently detected mutation was A2143G (86, 90%) followed by A2142G (11, 36%). Seven patients had a double mutation A2143G-A2142G. The factors independently associated with resistance to clarithromycin were diabetes, high blood pressure, the presence of a bulbar ulcer on endoscopy and the presence of gastric atrophy on histology.Conclusion. Detection of more than 25 % of strains with clarithromycin resistance mutations makes the H. pylori first-line treatment with clarithromycin questionable in our setting, and a review of empirical treatment of H. pylori is urgently needed.

Empiric treatment vs susceptibility-guided treatment for eradicating H. pylori: Is it possible to change that paradigm using modern molecular methods?

Helicobacter pylori (H. pylori) infection is the most widespread infectious-contagious disease worldwide, reaching a prevalence of 50-80% in developing countries. Chronic infection is considered the main cause of chronic gastritis and has been related to other diseases, such as peptic ulcer, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. The most common treatment is with eradication regimens that utilize three or four drugs, including a proton pump inhibitor (PPI) and the antibiotics, clarithromycin and amoxycillin or metronidazole. Empiric antibiotic use for eradicating the bacterium has led to a growing resistance to those drugs, reducing regimen efficacy and increasing costs for both the patient and the healthcare sector. In such a context, the development of noninvasive next-generation molecular methods holds the promise of revolutionizing the treatment of H. pylori. The genotypic and phenotypic detection of the resistance of the bacterium to antibiotics enables personalized treatment regimens to be provided, reducing costs and implementing an antibiotic stewardship program. The aims of the present narrative review were to analyze and compare the traditional and next-generation methods for diagnosing H. pylori, explain the different factors associated with eradication failure, and emphasize the impact of the increasing antibiotic resistance on the reversal and prevention of H. pylori-associated diseases.

Traditional and Modern Diagnostic Approaches in Diagnosing Pediatric Helicobacter pylori Infection

Helicobacter pylori (H. pylori) is the most common bacterial infection worldwide, is usually acquired during childhood and is related to gastric carcinogenesis during adulthood. Therefore, its early proper diagnosis and subsequent successful eradication represent the cornerstones of gastric cancer prevention. The aim of this narrative review was to assess traditional and modern diagnostic methods in terms of H. pylori diagnosis. Several invasive and non-invasive methods were described, each with its pros and cons. The invasive diagnostic methods comprise endoscopy with biopsy, rapid urease tests, histopathological exams, cultures and biopsy-based molecular tests. Among these, probably the most available, accurate and cost-effective test remains histology, albeit molecular tests definitely remain the most accurate despite their high costs. The non-invasive tests consist of urea breath tests, serology, stool antigens and non-invasive molecular tests. Urea breath tests and stool antigens are the most useful in clinical practice both for the diagnosis of H. pylori infection and for monitoring the eradication of this infection after therapy. The challenges related to accurate diagnosis lead to a choice that must be based on H. pylori virulence, environmental factors and host peculiarities.

Emphasizing the importance of successful eradication of Helicobacter pylori on initial treatment

Helicobacter pylori (H. pylori) infection is the most important risk factor for gastric cancer and plays an initiating role in the development of intestinal-type gastric cancer. Eradication of H. pylori significantly reduces the incidence and mortality of gastric cancer. International expert consensus recommends eradication treatment for all infected individuals unless competing considerations. However, large-scale H. pylori eradication treatments have led to increasing rates of resistance to multiple antibiotics, together with factors such as coccoid transformation, host CYP2C19 gene polymorphisms, and inappropriate treatment regimens, resulting in a gradual decline in H. pylori eradication rates. Currently, empirical and repeated eradication of H. pylori treatment is common in clinical practice, which will certainly lead to a further increase in antibiotic resistance, resulting in a great waste of medical resources and an increased psychological burden on patients and their relatives. Therefore, successful eradication of H. pylori on initial treatment should be given high priority, and the implementation of personalized treatment is essential.

New Strategy for the Detection and Treatment of Helicobacter pylori Infections in Primary Care Guided by a Non-Invasive PCR in Stool: Protocol of the French HepyPrim Study

Helicobacter pylori (Hp) infects half of the world population and is responsible for gastric, duodenal ulcers and gastric cancer. The eradication of Hp cures ulcers and prevents ulcer recurrences and gastric cancer. Antibiotic resistance of Hp, and particularly clarithromycin resistance, is the primary cause of treatment failure and is a major concern identified by the WHO as a high priority requiring research into new strategies. Treatments guided by the detection of antibiotic resistance have proven their medical and economical superiority. However, this strategy is severely hampered by the invasive nature of the fibroscopy, since antibiotic resistance detection requires gastric biopsies. The eradication of Hp involves primary care physicians. The objective of this study will be to evaluate the feasibility of a strategy for the management of Hp infection in primary care by a recently developed non-invasive procedure and its non-inferiority in eradication rates compared with the strategy recommended by the French National Authority of Health. The non-invasive procedure is a PCR on stool to detect Hp infection and mutations conferring resistance to clarithromycin allowing a treatment guided by the results of the PCR. We present the protocol of a prospective, multicenter, randomized, controlled interventional study in two arms.

Evolution of Diagnostic Methods for Helicobacter pylori Infections: From Traditional Tests to High Technology, Advanced Sensitivity and Discrimination Tools

Rapid diagnosis and treatment application in the early stages of H. pylori infection plays an important part in inhibiting the transmission of this infection as this bacterium is involved in various gastric pathologies such as gastritis, gastro-duodenal ulcer, and even gastric neoplasia. This review is devoted to a quick overview of conventional and advanced detection techniques successfully applied to the detection of H. pylori in the context of a compelling need to upgrade the standards of the diagnostic methods which are currently being used. Selecting the best diagnostic method implies evaluating different features, the use of one or another test depending on accessibility, laboratories equipment, and the clinical conditions of patients. This paper aims to expose the diagnosis methods for H. pylori that are currently available, highlighting their assets and limitations. The perspectives and the advantages of nanotechnology along with the concept of nano(bio)sensors and the development of lab-on-chip devices as advanced tools for H. pylori detection, differentiation, and discrimination is also presented, by emphasizing multiple advantages: simple, fast, cost-effective, portable, miniaturized, small volume of samples required, highly sensitive, and selective. It is generally accepted that the development of intelligent sensors will completely revolutionize the acquisition procedure and medical decision in the framework of smart healthcare monitoring systems.

Comparison of invasive histological and molecular methods in the diagnosis of Helicobacter pylori from gastric biopsies of Sudanese patients: a cross-sectional study

Background: The continuous rise in the number of patients suffering from Helicobacter pylori is probably due to the changes in modern life. Nowadays, patients suffering from gastrointestinal problems are diagnosed through invasive and non-invasive techniques. The choice of a diagnostic test is influenced by factors such as the tests' sensitivity and specificity, the clinical conditions, and the cost-effectiveness of the testing strategy. This study aimed to compare molecular detection methods of H. pylori by polymerase chain reaction (PCR) targeting the 16S rRNA, ureA and glmM genes with an invasive histopathological technique. Methods: 290 gastric biopsies were collected using gastrointestinal endoscopy from patients with gastritis symptoms in different hospitals in Khartoum state. Two gastric biopsies were collected from each patient for PCR and histopathology. Results: A total of 103 (35.5%) samples were positive by histopathological examination, 88 (30.3%) by 16S rRNA, 39 (13.4%) by glmM gene, and 56 (19.3%) by ureA gene. The highest sensitivity was observed in 16S rRNA (46.6%), followed by glmM (24.3%) and ureA (23.3%). While the best specificity was observed in glmM gene (92.5%), followed by ureA (82.3%) and 16S rRNA (78.6%). Conclusion: PCR test targeting the 16S rRNA gene exhibited the best results for molecular detection of H. pylori compared to other genes.

Who Could Be Blamed in the Case of Discrepant Histology and Serology Results for Helicobacter pylori Detection?

BACKGROUND

Discrepancies between histology and serology results for Helicobacter pylori detection could be caused by a variety of factors, including a biopsy sampling error, expertise of the pathologist, natural loss of infection due to advanced atrophy, or a false-positive serology in the case of a previous infection, since antibodies may be present in blood following recovery from the infection.

AIMS

To identify true H. pylori-positive individuals in discrepant cases by serology and histology using real time polymerase chain reaction (RT-PCR) as a gold standard.

METHODS

Study subjects with discrepant histology and serology results were selected from the GISTAR pilot study data base in Latvia. Subjects having received previous H. pylori eradication therapy or reporting use of proton pump inhibitors, antibacterial medications, or bismuth containing drugs one month prior to upper endoscopy were excluded. We compared the discrepant cases to the corresponding results of RT-PCR performed on gastric biopsies.

RESULTS

In total, 97 individuals with discrepant results were identified: 81 subjects were serology-positive/histology-negative, while 16 were serology-negative/histology-positive. Among the serology-positive/histology-negative cases, 64/81 (79.0%) were false-positives by serology and, for the majority, inflammation was absent in all biopsies, while, in the serology-negative/histology-positive group, only 6.2% were proven false-positives by histology.

CONCLUSIONS

Among this high H. pylori prevalent, middle-aged population, the majority of discrepant cases between serology and histology were due to false positive-serology, rather than false-negative histology. This confirms the available evidence that the choice of treatment should not be based solely on the serological results, but also after excluding previous, self-reported eradication therapy.

Helicobacter pylori diagnosis and therapy in the era of antimicrobial stewardship

The diagnosis and therapy of Helicobacter pylori infection have undergone major changes based on the use the principles of antimicrobial stewardship and increased availability of susceptibility profiling. H. pylori gastritis now recognized as an infectious disease, as such there is no placebo response allowing outcome to be assessed in relation to the theoretically obtainable cure rate of 100%. The recent recognition of H. pylori as an infectious disease has changed the focus to therapies optimized to reliably achieve high cure rates. Increasing antimicrobial resistance has also led to restriction of clarithromycin, levofloxacin, or metronidazole to susceptibility-based therapies. Covid-19 resulted in the almost universal availability of polymerase chain reaction testing in hospitals which can be repurposed to utilize readily available kits to provide rapid and inexpensive detection of clarithromycin resistance. In the United States, major diagnostic laboratories now offer H. pylori culture and susceptibility testing and American Molecular Laboratories offers next-generation sequencing susceptibility profiling of gastric biopsies or stools for the six commonly used antibiotics without need for endoscopy. Current treatment recommendations include (a) only use therapies that are reliably highly effective locally, (b) always perform a test-of-cure, and (c) use that data to confirm local effectiveness and share the results to inform the community regarding which therapies are effective and which are not. Empiric therapy should be restricted to those proven highly effective locally. The most common choices are 14-day bismuth quadruple therapy and rifabutin triple therapy. Prior guidelines and treatment recommendations should only be used if proven locally highly effective.

Listeria monocytogenes faecal carriage is common and depends on the gut microbiota

Listeria genus comprises two pathogenic species, L. monocytogenes (Lm) and L. ivanovii, and non-pathogenic species. All can thrive as saprophytes, whereas only pathogenic species cause systemic infections. Identifying Listeria species' respective biotopes is critical to understand the ecological contribution of Listeria virulence. In order to investigate the prevalence and abundance of Listeria species in various sources, we retrieved and analyzed 16S rRNA datasets from MG-RAST metagenomic database. 26% of datasets contain Listeria sensu stricto sequences, and Lm is the most prevalent species, most abundant in soil and host-associated environments, including 5% of human stools. Lm is also detected in 10% of human stool samples from an independent cohort of 900 healthy asymptomatic donors. A specific microbiota signature is associated with Lm faecal carriage, both in humans and experimentally inoculated mice, in which it precedes Lm faecal carriage. These results indicate that Lm faecal carriage is common and depends on the gut microbiota, and suggest that Lm faecal carriage is a crucial yet overlooked consequence of its virulence.

Regular arrangement of collecting venules (RAC) as an endoscopic marker for exclusion of Helicobacter pylori (H. pylori) infection: A systematic review and meta-analysis

BACKGROUND

Helicobacter pylori (H. pylori) is the most common cause of gastric cancer. Growing evidence suggests that the regular arrangement of collecting venules (RAC) can be used as an endoscopic marker to diagnose H. pylori infection. However, data on the diagnostic accuracy of RAC for H. pylori infection are conflicting. We performed a systematic review and meta-analysis of relevant studies to determine the diagnostic accuracy and clinical utility of RAC for the diagnosis of H. pylori infection.

METHODS

We systematically searched PubMed, Embase, Web of Science and the Cochrane Library between inception and Oct 29, 2020, for studies that assessed the diagnostic accuracy of RAC for H. pylori infection.

RESULTS

The literature search yielded 2921 non-duplicated screened titles, of which 58 underwent full-text review. Fifteen studies, representing a total of 6621 patients, met the inclusion criteria. The area under the summary receiver operating characteristic curve was 0.98 (95% CI 0.96-0.99). The pooled estimates for RAC were 0.98 (95% CI 0.95-0.99) for sensitivity and 0.75 (95% CI 0.54-0.88) for specificity. The pooled positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 3.8 (95% CI 1.9-7.7) and 0.03 (95% CI 0.02-0.07), respectively.

CONCLUSIONS

RAC can be used as an endoscopic marker for exclusion of H. pylori infection. However, it cannot be recommended as a single indicator for the confirmation of H. pylori infection. The conclusion of this study should be treated with caution because significant heterogeneity exists between the evaluated studies.

Development and Validation of Multiplex Quantitative PCR Assay for Detection of Helicobacter pylori and Mutations Conferring Resistance to Clarithromycin and Levofloxacin in Gastric Biopsy

Aims and Objectives

More than half of the world's population is infected with Helicobacter pylori, which can cause chronic gastritis. WHO has regarded clarithromycin-resistant H. pylori as a high priority pathogen. Hence, accurate diagnosis and detection of clarithromycin- and levofloxacin-resistant H. pylori strains is essential for proper management of infection. The objective of this study was to develop and optimize multiplex quantitative PCR assay for detection of mutations associated with clarithromycin and levofloxacin resistance in H. pylori directly from the gastric biopsies.

Materials and Methods

Specific primers and probes were designed to amplify ureA and mutations in 23S rRNA and gyrA genes. Singleplex and triplex qPCR assays were optimized and the assay's sensitivities and specificities were determined. The optimized multiplex qPCR assay was performed on 571 gastric biopsies.

Results

In this study, 14.7% (84/571) of the gastric biopsies were positive for H. pylori by conventional methods and 23.8% (136/571) were positive by the ureA-qPCR with 96.4% sensitivity and 88.5% specificity, while the +LR and -LR were 8.72 and 0.04, respectively. The ureA-positive samples (n=136) were subjected to multiplex qPCR which detected A2142G and A2143G mutations in the 23S rRNA gene (20.6%, 28/136) conferring clarithromycin resistance and gyrA mutations N87K, N87I, D91N, and D91Y (11.8%, 16/136) leading to levofloxacin resistance. The sensitivity and specificity of qPCR of 23S rRNA gene were 100% and 98.7%, respectively, while 100% and 99.8% for qPCR of gyrA, respectively.

Conclusion

The effectiveness of this qPCR is that it is sensitive in detecting low bacterial load and will help in timely detection of clarithromycin- and levofloxacin-resistant strains, especially in case of mixed infections. Since it is culture independent, it can inform clinicians about antibiotics to be included in the first-line therapy, thereby improving the management of H. pylori infection at a much greater pace.

Antibiotic Resistance Prevalence and Trends in Patients Infected with Helicobacter pylori in the Period 2013-2020: Results of the European Registry on H. pylori Management (Hp-EuReg)

Background: Bacterial antibiotic resistance changes over time depending on multiple factors; therefore, it is essential to monitor the susceptibility trends to reduce the resistance impact on the effectiveness of various treatments. Objective: To conduct a time-trend analysis of Helicobacter pylori resistance to antibiotics in Europe. Methods: The international prospective European Registry on Helicobacter pylori Management (Hp-EuReg) collected data on all infected adult patients diagnosed with culture and antimicrobial susceptibility testing positive results that were registered at AEG-REDCap e-CRF until December 2020. Results: Overall, 41,562 patients were included in the Hp-EuReg. Culture and antimicrobial susceptibility testing were performed on gastric biopsies of 3974 (9.5%) patients, of whom 2852 (7%) were naive cases included for analysis. The number of positive cultures decreased by 35% from the period 2013–2016 to 2017–2020. Concerning naïve patients, no antibiotic resistance was found in 48% of the cases. The most frequent resistances were reported against metronidazole (30%), clarithromycin (25%), and levofloxacin (20%), whereas resistances to tetracycline and amoxicillin were below 1%. Dual and triple resistances were found in 13% and 6% of the cases, respectively. A decrease (p < 0.001) in the metronidazole resistance rate was observed between the 2013–2016 (33%) and 2017–2020 (24%) periods. Conclusion: Culture and antimicrobial susceptibility testing for Helicobacter pylori are scarcely performed (<10%) in Europe. In naïve patients, Helicobacter pylori resistance to clarithromycin remained above 15% throughout the period 2013–2020 and resistance to levofloxacin, as well as dual or triple resistances, were high. A progressive decrease in metronidazole resistance was observed.

Methods for detection of Helicobacter pylori from stool sample: current options and developments

Accurate detection of Helicobacter pylori infection and determination of antibiotics have significant meaning in clinical practice. The detection methods can be categorized into two types, invasive and non-invasive, but nowadays we use the urease breath test most frequently which is non-invasive. However, many developing countries cannot meet the requirements for having specialized equipment and they lack trained personnel. Also, for the children, it is difficult to make them cooperate for the test. Methods that detect Helicobacter pylori from stool sample can be a promising alternative for detection used in children and mass screening. Stool antigen tests have several advantages such as rapidity, simplicity, and cheapness, though their results may be influenced by the heterogenicity of antigens, the nature of biochemical techniques, and the amount of antigen presented in the stool. PCR-based methods can specifically detect Helicobacter pylori infection and antibiotic resistance by targeting specific gene sequence, but they also are limited by the requirements of facilities and experts, the existence of inhibitory substance, and interference from the dead bacteria. Some novel methods also deserve our attention. Here we summarized the results of researches about methods using stool sample and we hope our work can help clinicians choose the appropriate test in clinical practice.

Current Helicobacter pylori Diagnostics

The high prevalence of Helicobacter pylori and the variety of gastroduodenal diseases caused by this pathogen necessitate the use of only accurate methods both for the primary diagnosis and for monitoring the eradication effectiveness. There is a broad spectrum of diagnostic methods available for detecting H. pylori. All methods can be classified as invasive or non-invasive. The need for upper endoscopy, different clinical circumstances, sensitivity and specificity, and accessibility defines the method chosen. This article reviews the advantages and disadvantages of the current options and novel developments in diagnostic tests for H. pylori detection. The progress in endoscopic modalities has made it possible not only to diagnose precancerous lesions and early gastric cancer but also to predict H. pylori infection in real time. The contribution of novel endoscopic evaluation technologies in the diagnosis of H. pylori such as visual endoscopy using blue laser imaging (BLI), linked color imaging (LCI), and magnifying endoscopy is discussed. Recent studies have demonstrated the capability of artificial intelligence to predict H. pylori status based on endoscopic images. Non-invasive diagnostic tests such as the urea breathing test and stool antigen test are recommended for primary diagnosis of H. pylori infection. Serology can be used for initial screening and epidemiological studies. The histology showed its value in detecting H. pylori and provided more information about the degree of gastric mucosa inflammation and precancerous lesions. Molecular methods are mainly used in detecting antibiotic resistance of H. pylori. Cultures from gastric biopsies are the gold standard and recommended for antibiotic susceptibility tests.

Diagnosis of Helicobacter pylori Infection and Recent Advances

BACKGROUND

Helicobacter pylori (H. pylori) infects approximately 50% of the world population. Its infection is associated with gastropathies, extra-gastric digestive diseases, and diseases of other systems. There is a canonical process from acute-on-chronic inflammation, chronic atrophic gastritis (CAG), intestinal metaplasia (IM), dysplasia, and intraepithelial neoplasia, eventually to gastric cancer (GC). H. pylori eradication abolishes the inflammatory response and early treatment prevents the progression to preneoplastic lesions.

METHODS

the test-and-treat strategy, endoscopy-based strategy, and screen-and-treat strategy are recommended to prevent GC based on risk stratification, prevalence, and patients' clinical manifestations and conditions. Challenges contain false-negative results, increasing antibiotic resistance, decreasing eradication rate, and poor retesting rate. Present diagnosis methods are mainly based on invasive endoscopy and noninvasive laboratory testing.

RESULTS

to improve the accuracy and effectiveness and reduce the missed diagnosis, some advances were achieved including newer imaging techniques (such as image-enhanced endoscopy (IEE), artificial intelligence (AI) technology, and quantitative real-time polymerase chain reaction (qPCR) and digital PCR (dPCR).

CONCLUSION

in the article, we summarized the diagnosis methods of H. pylori infection and recent advances, further finding out the opportunities in challenges.

Evaluation of the Effectiveness of Helicobacter pylori Eradication Regimens in Lithuania during the Years 2013-2020: Data from the European Registry on Helicobacter pylori Management (Hp-EuReg)

Background and Objectives: The prevalence of H. pylori in Eastern Europe remains quite high; however, there is insufficient data on the eradication regimens and their effectiveness. Therefore, the objective of the study was to evaluate the diagnostic methods and treatment of H. pylori infection as well as their adherence to Maastricht V/Florence consensus during the years 2013–2020 in Lithuania. Materials and Methods: Sub-study of the “European Registry on H. pylori Management” (Hp-EuReg), international multicenter prospective non-interventional registry of the routine clinical practice. Lithuanian data from the years 2013–2020 were analyzed for effectiveness on a modified intention-to-treat (mITT) basis. 2000 adult patients, diagnosed with H. pylori infection, were included. Data were compared to the European Maastricht V guidelines. Results: Triple-therapy was used in 90% of the cases. In 91% of the first-line prescriptions, standard triple therapy (STT) was used. The most common second-line treatment was a combination of PPI, amoxicillin and levofloxacin (PPI+A+L) (47%). The overall effectiveness in 552 cases valid for analysis was 90% by mITT. In first-line treatment, the STT effectiveness was 90% and second-line treatment with PPI+A+L achieved 92% by mITT. Increasing overall H. pylori eradication rates were observed: from 72% in 2013 to more than 90% in 2018–2020, as well as a shift from 7 to 10–14 days treatments duration throughout 2013–2020. Conclusions: In Lithuania, the prescribed eradication regimens for H. pylori were in accordance with the international guidelines but diagnostic methods and treatment duration only partially met Maastricht V/Florence guidelines. The eradication effectiveness was improved progressively during the years 2018–2020, reaching ≥90% cure rates.

What Is New in Helicobacter pylori Diagnosis. An Overview

Helicobacter pylori infection remains one of the most prevalent infections worldwide, especially in low-resource countries, and the major risk factor for peptic ulcer and gastric cancer. The “test-and-treat” strategy is recommended by several guidelines and consensus. The choice of testing method is based on patient age, presence of alarm signs and/or symptoms, use of non-steroidal anti-inflammatory drugs, as well as local availability, test reliability, and cost. Culture is the gold standard to detect H. pylori and, possibly, to perform susceptibility testing, however, it requires upper endoscopy and dedicated labs. Recent advances in molecular biology have provided new strategies in detecting infection and antimicrobial resistance without invasive tests. In this review we attempt to offer a comprehensive panorama on the new diagnostic tools and their potential use in clinical settings, in order to accomplish specific recommendations.