Current Helicobacter pylori Diagnostics

Change in Diagnosis of Helicobacter pylori Infection in the Treatment-Failure Era

Helicobacter pylori (H. pylori) infection is a prevalent global health issue, associated with several gastrointestinal disorders, including gastritis, peptic ulcers, and gastric cancer. The landscape of H. pylori treatment has evolved over the years, with increasing challenges due to antibiotic resistance and treatment failure. Traditional diagnostic methods, such as the urea breath test, stool antigen test, and endoscopy with biopsy, are commonly used in clinical practice. However, the emergence of antibiotic-resistant strains has led to a decline in treatment efficacy, necessitating a re-evaluation of common diagnostic tools. This narrative review aims to explore the possible changes in the diagnostic approach of H. pylori infection in the era of treatment failure. Molecular techniques, including polymerase chain reaction and whole genome sequencing, which have high sensitivity and specificity, allow the detection of genes associated with antibiotic resistance. On the other hand, culture isolation and a phenotypic antibiogram could be used in the diagnostic routine, although H. pylori is a fastidious bacterium. However, new molecular approaches are promising tools for detecting the pathogen and its resistance genes. In this regard, more real-life studies are needed to reveal new diagnostic tools suitable for identifying multidrug-resistant H. pylori strains and for outlining proper treatment.

Diagnostic value of IgG antibody and stool antigen tests for chronic Helicobacter pylori infections in Ibb Governorate, Yemen

The stool antigen test (SAT) and the serum Helicobacter pylori (H. pylori) IgG antibody assays exhibit significant utility in the clinical diagnosis of H. pylori infection and in distinguishing between acute and chronic infections. The main objective of the current study was to identify the diagnostic value of serum H. pylori IgG antibody and SAT in the detection of H. pylori infections among chronic H. pylori-infected patients residing in Ibb Governorate, Yemen. 200 patients with H. pylori infection, confirmed through positive results in the serum immunochromatographic antibody test, were selected for H. pylori infection confirmation using serum H. pylori IgG antibodies and SAT across diverse hospitals, gastroenterology, and Hepatology clinics in Ibb Governorate. After the selection of patients, blood and stool specimens were obtained from all participants and underwent analysis via the Statistical Package for the Social Sciences (SPSS). The prevalence of H. pylori infection demonstrated variability based on the confirmatory tests, with rates of 54% for SAT and 78.5% for serum H. pylori IgG antibody, contrasting with a 100% prevalence observed in the screening serum immunochromatographic antibody test. Clinically, the study categorized H. pylori infections into four stages, whereby a significant proportion of patients (40.5%) exhibited positivity for both serum H. pylori IgG antibody and SAT, indicative of active chronic infections. The majority of positive cases only manifested serum H. pylori IgG antibody presence (chronic infections) at 38%, whereas 13.5% exclusively tested positive for SAT, corresponding to acute infections. Moreover, 88% of patients did not have either serum H. pylori IgG antibody or SAT (absence of infections) during confirmatory tests. Noteworthy is the study's approach employing multiple tests for H. pylori infection detection, focusing predominantly on chronic infections-prevailing types caused by H. pylori. The results revealed a significant association between serum levels of H. pylori IgG antibody and SAT results with the presence of diverse gastrointestinal symptoms among patients, which increased with long H. pylori infection durations.

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.

Association of Helicobacter pylori with migraine headaches and the effects of this infection and its eradication on the migraine characteristics in adults: A comprehensive systematic review and meta-analysis

BACKGROUND

Migraine is one of the most common neurological disorders that can severely overshadow people's quality of life, and Helicobacter pylori infection is a health problem in different societies. During the last two decades, many original studies have been conducted on the various aspects of the relationship between these two disorders; however, they have reported different and sometimes contradictory results.

METHODS

This study was conducted based on the PRISMA protocol. We performed a comprehensive literature search in the online databases up to May 2023, and 22 studies that contained original data on the relationship between H. pylori infection and migraine headaches in adults were included. For performing the meta-analysis, we calculated the odds ratios (OR) and 95% confidence intervals (CI), using a random-effects model, and to determine the possible causes of heterogeneity, we conducted a subgroup meta-analysis.

RESULTS

The overall OR for the association of H. pylori infection and migraine headaches through 493,794 evaluated individuals was 2.80 [95% CI = 1.75-4.48; I2  = 89.20, p < 0.01], which reveals a statistically significant association between these disorders. It was found that the studies that were conducted in Asian regions and the recently published ones have clearly shown a higher association between migraine and H. pylori infection. On the other hand, migraine patients who are infected with H. pylori have similar signs and symptoms as H. pylori-negative migraineurs; meanwhile, the clinical trials conducted in this field strongly emphasize the benefits of eradicating H. pylori infection in migraine patients and have estimated its effectiveness in improving migraine headaches equivalent to current common migraine treatments. Furthermore, it was reported that white matter lesions were 2.5-fold higher on brain MRI in patients with H. pylori-positive migraine compared with H. pylori-negative migraineurs; however, the evidence does not support the role of oxidative stress in patients suffering from H. pylori infection and migraine and refuses the role of Cag-A-positive strains of H. pylori in migraine headaches.

CONCLUSION

According to the currently available data, it seem reasonable that patients with a definite diagnosis of migraine who also suffer from gastrointestinal problems, undergo the H. pylori detection tests and if the evaluations are positive, H. pylori eradication treatment can be considered even before any migraine treatment.

The Impact of the Angulus Biopsy on the Detection of Staging and the Grading of Chronic Gastritis

There is a generally recognized need for a morphological assessment of the individual risk of developing gastric cancer in a patient with chronic gastritis, according to the OLGA system (Operative Link for Gastritis Assessment). At the same time, the role of assessing the biopsy from the incisura angularis remains controversial. The aim of our study was to assess the value of incisura angularis biopsy in staging gastritis according to the OLGA system by examining the atrophic and inflammatory changes in the antrum, incisura angularis, and body.

MATERIALS AND METHODS

A total of 718 patients (576 women and 142 men) aged 20 to 84 years were examined. Most of the patients were in the age group of 50 to 70 years (54.6%). Depending on the detection of H. pylori and autoimmune gastritis markers, all patients were divided into three groups. The first group included 380 patients with H. pylori gastritis without signs of autoimmune gastritis. The second group consisted of 209 patients with autoimmune gastritis, in whom no infection was detected during the examination, and there were no indications of H. pylori eradication. The third group consisted of 129 patients with chronic gastritis of combined etiology (autoimmune and H. pylori). Endoscopy biopsies were taken according to the updated Sydney System. Histological assessments of the grade and the stage of gastritis were carried out according to the standard OLGA-based protocol. Then, the same assessments were evaluated without taking into account histological changes in the incisura angularis.

RESULTS

When assessing the severity of inflammatory changes in the gastric mucosa according to the OLGA system, grade II (72.3%) was most often detected in all groups of patients. A severe degree of activity of chronic gastritis was most often observed in the group of patients with H. pylori gastritis (6.1%). These indicators practically did not change if the assessment did not take the angulus biopsy into account. When assessing the severity of atrophy of the glands in the gastric mucosa in patients of the first group, mild stages of atrophy prevailed. Without taking into account the angulus biopsy, a decrease in the stage of atrophy was observed in 27 cases (7.11%), and in only 4 cases did stage IV change to stage III, while in 23 cases, discrepancies were noted only within groups with a mild stage of atrophy. There were no transitions from stage III to stage II. In the group of patients with autoimmune gastritis, pronounced stages of atrophy prevailed-in more than 77%. Without taking into account the angulus biopsy, a decrease in the stage of atrophy was observed in eight cases (3.83%), and in three (1.4%) patients, stage III was changed to stage II. In the group of patients with combined etiology (autoimmune + H. pylori), severe stages of atrophy also prevailed (70.5%). A decrease in the stage of atrophy without taking into account the angulus biopsy was only observed in three patients (2.32%), of which two cases concerned patients with mild stages of atrophy. Thus, in general, severe stages of atrophy of the gastric mucosa (stages III and IV according to the OLGA staging system) were detected in 313 patients (43.59%). If the assessment of the atrophy stage did not take into account changes in the angulus biopsy, then severe stages of atrophy (III and IV according to OLGA) were detected in 310 patients (43.17%). In total, changes in the assessment of the atrophy stage occurred in 38 patients (5.29%), and this was more often observed in patients with stages I and II of atrophy.

CONCLUSIONS

Accounting for histological changes in the incisura angularis does not significantly affect the assessment of the grade and stage of chronic gastritis according to the OLGA system, regardless of the etiology of atrophic gastritis.

The Importance of Artificial Intelligence in Upper Gastrointestinal Endoscopy

Recently, there has been a growing interest in the application of artificial intelligence (AI) in medicine, especially in specialties where visualization methods are applied. AI is defined as a computer's ability to achieve human cognitive performance, which is accomplished through enabling computer "learning". This can be conducted in two ways, as machine learning and deep learning. Deep learning is a complex learning system involving the application of artificial neural networks, whose algorithms imitate the human form of learning. Upper gastrointestinal endoscopy allows examination of the esophagus, stomach and duodenum. In addition to the quality of endoscopic equipment and patient preparation, the performance of upper endoscopy depends on the experience and knowledge of the endoscopist. The application of artificial intelligence in endoscopy refers to computer-aided detection and the more complex computer-aided diagnosis. The application of AI in upper endoscopy is aimed at improving the detection of premalignant and malignant lesions, with special attention on the early detection of dysplasia in Barrett's esophagus, the early detection of esophageal and stomach cancer and the detection of H. pylori infection. Artificial intelligence reduces the workload of endoscopists, is not influenced by human factors and increases the diagnostic accuracy and quality of endoscopic methods.

Integrated RPA-CRISPR/Cas12a system towards Point-of-Care H. pylori detection

The rapidly advanced CRISPR/Cas biosensing technology provides unprecedent potential for the development of novel biosensing systems. It provides a new approach for realizing rapid, sensitivity and highly specific pathogen nucleic acid detection, with the capability to combine other technologies, including Polymerase Chain Reaction or isothermal amplifications. The detection of Helicobacter pylori (H. pylori), one of the most common human pathogens to cause various gastroduodenal diseases, has also been explored with the assistance of CRISPR/Cas systems. However, gaps still remain for the development of end-user friendly sensing systems.In this study, a combined RPA-CRISPR/Cas12a biosensing system has been established. It shown the capability to quantitively detect the presence of H. pylori genome DNA with 4 orders of magnitude linear range, and sensitivity of 1.4 copies/µL. The overall reaction can be done within 45 mins at room temperature, which eliminates the needs for heating instrumentation. In addition, with the addition of pullulan as a protective reagent, the potential of storing CRISPR/Cas12a system reagents by using a freeze-dry approach has also been demonstrated.Clinical Relevance - This study represents a novel exploration to applying CRISPR/Cas12a-based biosensing technology to the detection of pathogen DNA with improved potential for the development of Point-of-Care diagnostics. This critical aspect of our technology will contribute to address the newly emerged pathogenic threats and support public health systems.

Prevalence of Helicobacter pylori genotypes: cagA, vacA (m1), vacA (s1), babA2, dupA, iceA1, oipA and their association with gastrointestinal diseases. A cross-sectional study in Quito-Ecuador

BACKGROUND

The most prevalent stomach infection in the world is caused by Helicobacter pylori (H. pylori). Several pathogenicity genes, including cagA, vacA, babA2, dupA, iceA, and oipA, are associated with an increased risk of gastrointestinal disease such as peptic ulcer and stomach cancer. This research aims to determine the prevalence of different H. pylori genotypes and correlate their risk in the development of gastrointestinal diseases in the Ecuadorian population.

METHODS

A cross-sectional research of 225 patients at the Calderón Hospital in Quito, Ecuador, was conducted. End point PCRs were run to determine the presence of 16S rRNA, cagA, vacA (m1), vacA (s1), babA2, dupA, iceA1, and oipA virulence genes. Chi-square test, odds ratios (OR) and 95% confidence intervals (CI) were utilized for the statistical analysis.

RESULTS

H. pylori infection was present in 62.7% of people. Peptic ulcers were seen in 22.2% and malignant lesions in 3.6% of patients. Genes oipA (93.6%), vacA (s1) (70.9%), and babA2 (70.2%) were the most prevalent. cagA/vacA (s1m1) and cagA/oipA (s1m1) combinations were found in 31.2% and 22.7% of the cases, respectively. Acute inflammation has a significant correlation with the genes cagA (OR = 4.96 95% CI: 1.1-22.41), babA2 (OR = 2.78 95% CI: 1.06-7.3), and the cagA/oipA combination (OR = 4.78, 95% CI: 1.06-21.62). Follicular hyperplasia was associated with iceA1 (OR = 3.13; 95% CI: 1.2-8.16), babA2 (OR = 2.56; 95% CI: 1.14-5.77), cagA (OR = 2.19; 95% CI: 1.06-4.52), and the cagA/oipA combination (OR = 2.32, 95% CI: 1.12-4.84). The vacA (m1) and vacA (s1m1) genes were associated with gastric intestinal metaplasia (OR = 2.71 95% CI: 1.17-6.29) (OR = 2.33 95% CI: 1.03-5.24). Finally, we showed that cagA/vacA (s1m1) gene combination increased the risk of duodenal ulcer development (OR = 2.89, 95% CI 1.10-7.58).

CONCLUSION

This study makes a significant contribution by offering genotypic information regarding H. pylori infection. The presence of several H. pylori genes was associated with the onset of gastrointestinal illness in the Ecuadorian population.

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.

Current trends in <i>Helicobacter pylori</i> eradication therapy

According to the Maastricht VI consensus, the triple therapy (PPI + clarithromycin + amoxicillin) and bismuth-based quadruple therapy (PPI + bismuth + tetracycline + metronidazole) are considered and may be proscribed empirically as first-line regimens in the regions with low clarithromycin resistance rates (<15%). In the regions with high clarithromycin resistance rates (> 15%), as well as in the regions with unknown resistance to this antibacterial agent, it is recommended to use classical quadruple therapy with bismuth drugs as the main choice and quadruple therapy without bismuth drugs (“simultaneous” or “concomitant”) as an alternative. The second-line regimens of empiric choice (when antimicrobial susceptibility testing is not available) include fluoroquinolone-based quadruple therapy (PPI + levofloxacin + amoxicillin + bismuth) or fluoroquinolone-based triple therapy (PPI + levofloxacin + amoxicillin) and bismuth-based quadruple therapy. The Maastricht VI consensus regulates the use of rifabutin-based triple therapy (PPI + amoxicillin + rifabutin) as a “rescue” therapy, if the above ET schemes are ineffective and there is no possibility to conduct an antimicrobial susceptibility test. In its latest clinical guidelines, the Russian Gastroenterological Association (RGA) recommends with a view to achieving maximum treatment efficiency during classic triple ET and levelling the risk of further progression of clarithromycin resistance in Russia to take additional measures to increase its effectiveness (detailed instruction of a patient and control over strict adherence to the prescribed regimen, prolonging the course up to 14 days; prescribing PPI at increased dose twice a day; the latest generation PPIs (rabeprazole and esomeprazole); adding bismuth tripotassium dicitrate (240 mg 2 times a day) to the standard triple therapy; adding cytoprotector rebamipide (100 mg 3 times a day) to the standard triple therapy; adding a probiotic with proven efficacy to the standard triple therapy within controlled studies).

Novel Sensitive Electrochemical Immunosensor Development for the Selective Detection of HopQ H. pylori Bacteria Biomarker

Helicobacter pylori (H. pylori) is a highly contagious pathogenic bacterium that can cause gastrointestinal ulcers and may gradually lead to gastric cancer. H. pylori expresses the outer membrane HopQ protein at the earliest stages of infection. Therefore, HopQ is a highly reliable candidate as a biomarker for H. pylori detection in saliva samples. In this work, an H. pylori immunosensor is based on detecting HopQ as an H. pylori biomarker in saliva. The immunosensor was developed by surface modification of screen-printed carbon electrodes (SPCE) with MWCNT-COOH decorated with gold nanoparticles (AuNP) followed by HopQ capture antibody grafting on SPCE/MWCNT/AuNP surface using EDC/S-NHS chemistry. The sensor performance was investigated utilizing various methods, such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and scanning electron microscope (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX). H. pylori detection performance in spiked saliva samples was evaluated by square wave voltammetry (SWV). The sensor is suitable for HopQ detection with excellent sensitivity and linearity in the 10 pg/mL-100 ng/mL range, with a 2.0 pg/mL limit of detection (LOD) and an 8.6 pg/mL limit of quantification (LOQ). The sensor was tested in saliva at 10 ng/mL, and recovery of 107.6% was obtained by SWV. From Hill's model, the dissociation constant Kd for HopQ/HopQ antibody interaction is estimated to be 4.60 × 10^-10 mg/mL. The fabricated platform shows high selectivity, good stability, reproducibility, and cost-effectiveness for H. pylori early detection due to the proper choice of biomarker, the nanocomposite material utilization to boost the SPCE electrical performance, and the intrinsic selectivity of the antibody-antigen approach. Additionally, we provide insight into possible future aspects that researchers are recommended to focus on.

Helicobacter pylori infection

Helicobacter pylori infection causes chronic gastritis, which can progress to severe gastroduodenal pathologies, including peptic ulcer, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. H. pylori is usually transmitted in childhood and persists for life if untreated. The infection affects around half of the population in the world but prevalence varies according to location and sanitation standards. H. pylori has unique properties to colonize gastric epithelium in an acidic environment. The pathophysiology of H. pylori infection is dependent on complex bacterial virulence mechanisms and their interaction with the host immune system and environmental factors, resulting in distinct gastritis phenotypes that determine possible progression to different gastroduodenal pathologies. The causative role of H. pylori infection in gastric cancer development presents the opportunity for preventive screen-and-treat strategies. Invasive, endoscopy-based and non-invasive methods, including breath, stool and serological tests, are used in the diagnosis of H. pylori infection. Their use depends on the specific individual patient history and local availability. H. pylori treatment consists of a strong acid suppressant in various combinations with antibiotics and/or bismuth. The dramatic increase in resistance to key antibiotics used in H. pylori eradication demands antibiotic susceptibility testing, surveillance of resistance and antibiotic stewardship.

A visual denaturation bubble-mediated strand exchange amplification and RGB visual analysis-based assay for quantitative detection of Helicobacter pylori in saliva

Helicobacter pylori (H. pylori) is a class I carcinogen causing gastric cancer. Almost 50% of people on earth have been infected and it is worse in developing countries. Early diagnosis of H. pylori infection is the most important strategy for preventing the spread and worse consequences. H. pylori can be isolated from human saliva, and the sampling of saliva is easy and convenient. Therefore, we developed a visual denaturation bubble-mediated strand exchange amplification and RGB visual analysis-based assay for quantitative detection of H. pylori in saliva in this study. Under the optimized reaction temperature and time, the SEA reaction could be finished in 30 min with a simple reaction system and low dependency on equipment. The detection results could be qualitatively identified by the naked eye and quantitatively analyzed by a developed RGB visual analysis method. The limit of detection (LOD) of RGB visual analysis was 10.8 CFU/mL. This assay had good specificity and anti-interference capacity. In the artificial contamination test, the recovery rate of our assay was between 99.3% and 111.5%, with RSD values ranging from 1.7% to 3.5%. These indicated our assay also had good reliability in the detection of saliva. We believe this assay showed good potential for better non-invasive diagnosis of H. pylori infection.

Linked Color Imaging for Stomach

Image-enhanced endoscopy (IEE) plays an important role in the detection and further examination of gastritis and early gastric cancer (EGC). Linked color imaging (LCI) is also useful for detecting and evaluating gastritis, gastric intestinal metaplasia as a pre-cancerous lesion, and EGC. LCI provides a clear excellent endoscopic view of the atrophic border and the demarcation line under various conditions of gastritis. We could recognize gastritis as the lesions of the diffuse redness to purple color area with LCI. On the other hand, EGCs are recognized as the lesions of the orange-red, orange, or orange-white color area in the lesion of the purple color area, which is the surround atrophic mucosa with LCI. With further prospective randomized studies, we will be able to evaluate the diagnosis ability for EGC by IEE, and it will be necessary to evaluate the role of WLI/IEE and the additional effects of the diagnostic ability by adding IEE to WLI in future.

Establishment and Methodological Evaluation of a Method for Rapid Detection of Helicobacter pylori and Virulence Genes Based on CRISPR-Cas12a

Introduction

More than half of the world's people are infected or have been infected with Helicobacter pylori. This infection is related to many diseases, with its pathogenicity related to virulence factors. Therefore, the rapid diagnosis of H. pylori and genotyping of virulence genes play an extremely important role in the clinical treatment and control of transmission.

Methods

To this end, we developed a molecular detection method based on RPA- CRISPR-Cas12a technology for the specific genes 16S rDNA gene, cytotoxin associated gene A(cagA), and vacuolating cytotoxin A (vacA) of H. pylori.

Results

The results of which were displayed by lateral flow strips. Macroscopic observation takes only about 25 minutes and the sensitivity is 2ng/microliter.

Discussion

The method is simple, convenient to operate and has low costs, and can therefore be applied widely to the detection and typing of H. pylori in various environments such as primary hospitals, community clinics, outdoors, and large medical institutions.

Analysis of high risk factors for chronic atrophic gastritis

BACKGROUND

Screening for chronic atrophic gastritis (CAG) is crucial for the prevention and early detection of gastric cancer. Endoscopy is the main method of CAG diagnosis, with high training requirements and limited accuracy, making it difficult to popularize. The study attempts to improve the positive rate and accuracy of CAG screening through non-invasive testing.

METHODS

A total of 2564 patients who underwent gastroscopy were included in this study. The results of gastroscopic evaluation, histological biopsy results (including H. pylori biopsy), urea breath test (UBT) results, serum pepsinogen, and testosterone were statistically analyzed.

RESULTS

We found significant differences in the diagnosis of CAG between endoscopy and histological biopsy. Pepsinogen II and pepsinogen I/II ratio were more useful for the diagnosis of CAG compared with pepsinogen I. The risk of CAG was increased when pepsinogen II exceeded 11.05 μg/L, and the pepsinogen I/II ratio was less than 3.75. CAG positivity was higher in patients with positive H. pylori infection on UBT screening. In addition, higher levels of testosterone, SHBG and HSD17B2, and lower level of GNRH1 were found in CAG mucosa. Patients with high serum testosterone had a higher risk of CAG.

CONCLUSION

CAG screening should be combined with endoscopic evaluation, biopsy, and other non-invasive tests. Non-invasive tests include the combination of serum pepsinogen II protein and pepsinogen I/II ratio and high level of serum testosterone. UBT combined with serum pepsinogen testing may improve the positive rate of CAG and reduce gastric mucosal damage from multiple biopsies.

Clinical Practice Guidelines of Russian Gastroenterological Association, Scientific Society for the Clinical Study of Human Microbiome, Russian Society for the Prevention of Non-Communicable Diseases, Interregional Association for Clinical Microbiology and Antimicrobial Chemotherapy for <i>H. pylori</i> Diagnostics and Treatment in Adults

Aim: bring to the attention of practitioners indications for anti-Helicobacter therapy, methods and procedure for diagnostics and eradication therapy of Н. pylori infection.

Key points. Chronic gastritis caused by Н. pylori infection, including asymptomatic persons, may be considered as an indication for eradication therapy of Н. pylori as etiological therapy and opportunistic screening for gastric cancer prevention. Indications, for obligatory anti-Helicobacter therapy include peptic ulcer, gastric MALT lymphoma, early gastric cancer (EGC) with endoscopic resection. H. pylori primary diagnostics methods include 13C-urea breath test, H. pylori stool antigen lab test, rapid urease test and serological method. The serological method cannot be used after anti-Helicobacter therapy.

In Russia H. pylori strains' resistance to clarithromycin does not exceed 15 % in most regional studies. The first line therapy for Н. pylori infection eradication is the standard triple therapy including a proton pump inhibitor (PPI), clarithromycin and amoxicillin, enhanced with bismuthate tripotassium dicitrate. A classic four-component therapy based on bismuthate tripotassium dicitrate or quadrotherapy without bismuth drug products which includes PPI, amoxicillin, clarithromycin and metronidazole, may be used as alternative to the first line eradication therapy. The standard triple therapy may be prescribed for 14 days only in those regions, where it has been proven to be effective. Quadrotherapy with bismuthate tripotassium dicitrate is also used as main second line therapy in case of standard triple therapy, bismuth enhanced standard triple therapy or combined therapy failure. Another second line therapy includes PPI, levofloxacin and amoxicillin, to which a bismuth-containing drug product may be added. The third line therapy is selected individually based on previously used treatment settings.

Conclusion. In each case of H. pylori infection the decision for eradication therapy should be made, which is especially relevant as eradication of H. pylori has been recognized as an effective measure for the prevention of gastric cancer.

Clinical Practice Guidelines of Russian Gastroenterological Association, Scientific Society for the Clinical Study of Human Microbiome, Russian Society for the Prevention of Non-Communicable Diseases, Interregional Association for Clinical Microbiology and Antimicrobial Chemotherapy for <i>H. pylori</i> Diagnostics and Treatment in Adults

Aim: bring to the attention of practitioners indications for anti-Helicobacter therapy, methods and procedure for diagnostics and eradication therapy of Н. pylori infection.

Key points. Chronic gastritis caused by Н. pylori infection, including asymptomatic persons, may be considered as an indication for eradication therapy of Н. pylori as etiological therapy and opportunistic screening for gastric cancer prevention. Indications, for obligatory anti-Helicobacter therapy include peptic ulcer, gastric MALT lymphoma, early gastric cancer (EGC) with endoscopic resection. H. pylori primary diagnostics methods include 13C-urea breath test, H. pylori stool antigen lab test, rapid urease test and serological method. The serological method cannot be used after anti-Helicobacter therapy.

In Russia H. pylori strains' resistance to clarithromycin does not exceed 15 % in most regional studies. The first line therapy for Н. pylori infection eradication is the standard triple therapy including a proton pump inhibitor (PPI), clarithromycin and amoxicillin, enhanced with bismuthate tripotassium dicitrate. A classic four-component therapy based on bismuthate tripotassium dicitrate or quadrotherapy without bismuth drug products which includes PPI, amoxicillin, clarithromycin and metronidazole, may be used as alternative to the first line eradication therapy. The standard triple therapy may be prescribed for 14 days only in those regions, where it has been proven to be effective. Quadrotherapy with bismuthate tripotassium dicitrate is also used as main second line therapy in case of standard triple therapy, bismuth enhanced standard triple therapy or combined therapy failure. Another second line therapy includes PPI, levofloxacin and amoxicillin, to which a bismuth-containing drug product may be added. The third line therapy is selected individually based on previously used treatment settings.

Conclusion. In each case of H. pylori infection the decision for eradication therapy should be made, which is especially relevant as eradication of H. pylori has been recognized as an effective measure for the prevention of gastric cancer.

Helicobacter pylori infection and risk of multiple sclerosis: An updated meta-analysis

BACKGROUND

There is considerable controversy around the question as to whether Helicobacter pylori (H. pylori) infection has a protective or causative role in the development of multiple sclerosis (MS). This study evaluated published information to assess the association between H. pylori infection and MS.

METHODS

We conducted a comprehensive systematic review of relevant observational studies in international databases. A random-effects model was used to calculate pooled odds ratio (OR) and 95% confidence interval (CI). I² statistic was used to assess the between-study heterogeneity. Subgroup and meta-regression analyses were applied to identify the source of heterogeneity.

RESULTS

In total, 22 studies (25 datasets) were eligible for the meta-analysis: 17 datasets had prevalence data and eight datasets had data on the mean titer of anti-H. pylori IgG. The pooled prevalence of H. pylori was 44.1% (908/2606) in the MS patients and 46.1% (1016/2200) in the controls, indicating a non-significant protective effect of H. pylori on MS (OR, 0.82; 95%CI, 0.58-1.17). In the subgroup analysis, studies that used ELISA yielded a significant protective association (OR, 0.59; 95%CI, 0.46-0.77), while a positive non-significant association (OR, 1.33; 95%CI, 0.83-2.15) was found from studies that used other serological methods; interestingly, a significant positive association (OR, 6.64; 95%CI, 2.40-13.76) was found from studies that used histological methods to detect H. pylori infection.

CONCLUSIONS

Our findings do not support the hypothesis that H. pylori infection represents a protective factor against the development of MS; however, the results varied depending on the diagnostic method(s). Particularly, a significant positive association was identified when studies introduced results based on histological examination, suggesting that active H. pylori infection might be a risk factor for development of MS. Thus, further studies are needed utilizing accurate diagnostic methods to elucidate the association between active H. pylori infection and MS.

Synchronous early gastric and intestinal mucosa-associated lymphoid tissue lymphoma in a Helicobacter pylori-negative patient: A case report

BACKGROUND

Mucosa-associated lymphoid tissue (MALT) lymphoma occurs largely in the digestive tract, with the stomach being the most commonly affected organ, followed by the small intestine, large intestine, and esophagus. It is rarely found in both the stomach and colon. Helicobacter pylori (H. pylori) infection is strongly associated with gastric MALT lymphoma, although there is a small number of H. pylori-negative gastric MALT lymphomas. Diagnosis of MALT lymphoma is challenging because of nonspecific symptoms and diverse presentations of endoscopic findings.

CASE SUMMARY

We report a case of an asymptomatic patient who during screening endoscopy and was found to have stromal tumor-like submucosal uplift lesions in the stomach body and polypoid lesions in the rectum. After endoscopic resection, the patient was diagnosed with multiple early simultaneous gastrointestinal MALT lymphomas.

CONCLUSION

This study may help improve our understanding of MALT lymphomas and multifocal lesions treated using early endoscopy.

Helicobacter pylori-Positive Gastric Biopsies-Association with Clinical Predictors

Introduction: Although Helicobacter pylori’s role in gastric oncogenesis is well-known, only a fraction of infected patients develop cancer. Hence, more factors are supposed to be involved. The objectives of the present study were to investigate the impact of clinicopathological parameters on Helicobacter pylori status. Methods: The study included 1522 patients referred for endoscopy: study group consisted of 557 patients with Helicobacter pylori-positive biopsies confirmed using histochemical stains or immunohistochemistry methods; and the control group consisted of 965 patients with Helicobacter pylori-negative status on histology. Results: Severe endoscopic lesions were more frequent in the Helicobacter pylori group (p < 0.001), with no difference noticed in the distribution of premalignant gastric lesions (p = 0.82). Anemia and dyslipidemia were independent factors associated with Helicobacter pylori-positive biopsies (p < 0.05). Non-steroidal anti-inflammatory therapy was more frequently administered in the study group, while proton-pump inhibitors had an anti-Helicobacter pylori activity on histology (p < 0.0001). Conclusion: In the studied population, patients with Helicobacter pylori-positive biopsies had a more frequent history of gastrotoxic medication, severe endoscopic lesions, and anemia. Helicobacter pylori was unpredictable by gastrointestinal symptoms. The frequency of premalignant gastric lesions was similar irrespective of the actual status of infection, underlining the importance of unintentional clearance of bacteria in old infection and the remaining risk for cancer in this population.

Diagnosis and Comparison of Three Invasive Detection Methods for Helicobacter pylori Infection

BACKGROUND

The purpose of this study was to compare different invasive methods for Helicobacter pylori (H. pylori) detection, namely PCR for H. pylori specific ureC gene, Rapid urease test (RUT), and histopathological examination by modified Giemsa staining.

METHODOLOGY

Endoscopic gastroduodenal biopsy materials were collected from dyspeptic patients who underwent endoscopic examination upon fulfilling the inclusion criteria. Three to four samples were collected from each patient after taking informed consent and proper clinical history. A rapid urease test (RUT) was done on spot with in-house RUT media from 1 specimen. One to two specimens were preserved in 10% formaldehyde for histopathology and PCR for ureC gene was done from 1 specimen. Collected biopsy specimens from gastric and duodenal mucosa of 142 patients were categorized as H. pylori-positive cases and H. pylori-negative cases based on the case definition used in the study upon positivity of 3 diagnostic tests.

RESULTS

Among 142 biopsy specimens, 34.5% were categorized as H. pylori-positive cases, 35.2% as H. pylori-negative cases, and finally 30.2% as doubtful or indeterminate cases. Rapid urease test was the most sensitive method, closely followed by ureC gene PCR and histopathology, with a sensitivity of 94.2%, 83.0%, and 76.5%, respectively. Whereas histology was the most specific, having 98.0% specificity followed by 83.0% in PCR. RUT was the least specific, with 55.5% specificity.

CONCLUSION

While histopathology could detect H. pylori infection with the highest specificity, for definitive diagnosis combination of any 2 methods should be used, if available.

Detection and Treatment of Helicobacter pylori: Problems and Advances

Helicobacter pylori (H. pylori) infection is chronic and etiologically linked to gastric cancer (GC) derived from gastric epithelium. The potential mechanism is complex, covering chronic inflammation, epithelial senescence, NF-κB activation, the cytotoxin-associated gene A protein translocation, and related abnormal signaling pathways. In clinical practice, the test-and-treat strategy, endoscopy-based strategy, and (family-based) screen-and-treat strategy are recommended to detect H. pylori and prevent GC. It has been demonstrated that the decreasing annual incidence of GC is largely attributable to the management of H. pylori. This study reviews the current clinical practice of H. pylori on the detection and eradication, alternative treatment strategies, and related problems and advances, and hopes to contribute to the better clinical management of H. pylori.

Comparison of Different Histological Staining Methods for Detection of Helicobacter pylori Infection in Gastric Biopsy

Background: Helicobacter pylori gastritis affects two-thirds of the world's human population. Among various invasive and non-invasive tests, histology play a very important role in detecting H. pylori in gastric biopsies. In histology, for detection of H. pylori, we use different histological staining techniques like routine haematoxylin & eosin (H&E) stain, Giemsa stain, Gimenez stain, and periodic acid Schiff - Alcian blue (PAS-AB) stain.

Objective: Aim of our study was to evaluate these different histopathological staining techniques for detecting H. pylori in gastric mucosal biopsies and to determine the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of H&E stain, Gemenez stain and PAS-AB in the detection of H. pylori in gastric biopsies using Giemsa stain as the reference standard.

Materials and Methods: It was a prospective descriptive study design of 45 gastric biopsies of patients having gastritis. This study was conducted at Vivekananda Polyclinic and Institute of Medical Sciences over a period of one year, from March 2021 to February 2022. From each formalin-fixed paraffin-embedded block, four glass slides were prepared and stained with H&E stain, Giemsa stains, Gemenez stain, and PAS-AB stain to detect the presence/absence of H. pylori in gastric biopsies. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were assessed.

Results: Various staining techniques for detecting H. pylori in gastric mucosal biopsies were compared. In reference to Giemsa stain results, statistical analysis indicates that the diagnostic accuracy of the Gimenez stain, H&E stain, and PAS-AB stain were 95.6%, 91.1%, and 84.4% respectively. Gimenez stain is confirmed to be better than H&E stain and PAS-AB stain to detect H. pylori in 45 gastric biopsies of patients having gastritis. PAS-AB stain is the worst stain to detect H. pylori in gastric biopsies.

Conclusion: Gimenez stain has higher diagnostic accuracy than PAS-AB stain in the detection of H. pylori in gastric biopsy. In fact, Gimenez stain has high sensitivity, specificity and diagnostic accuracy as compared to traditional H&E stain while PAS-AB stain has lower sensitivity, specificity and diagnostic accuracy. Thus, Gimenez stain is also recommended for the detection of H. pylori in gastric biopsy.

Effectiveness of Rebamipide as a part of the <i>Helicobacter pylori</i> eradication therapy in Russia: a meta-analysis of controlled trials

Aim. To perform a meta-analysis of the data on Rebamipide efficacy and safety as a part of Helicobacter pylori eradication therapy in Russian patients. Materials and methods. A search for original studies was conducted in the electronic database of the Russian Science Citation Index (RSCI) on the Scientific Electronic Library (SEL Elibrary.ru). Google (Google.com) was used for the "grey" search. All Russian controlled studies comparing the efficacy and/or safety of Rebamipide as a part of the regimen of H. pylori eradication therapy were included in the final analysis. Results. In 6 included controlled trials with a cumulative population (considering double comparisons between multiple groups) of 531 patients (273 in Rebamipide groups and 258 in groups without Rebamipide), the pooled eradication effectiveness was 90.376% (95% confidence interval CI 86.31193.560) in patients receiving Rebamipide and 81.681% (95% CI 76.49986.141) in patients receiving eradication regimens without Rebamipide. The meta-analysis showed that the Rebamipide addition to eradication regimens significantly improved efficacy (odds ratio 2.162, 95% CI 1.2683.685; p=0.005). No significant heterogeneity was found between study results (p=0.863; I2=0.00%); therefore, a fixed effects model was used in the resulting analysis. In addition, the meta-analysis of included studies showed a reduction of adverse events (odds ratio 0.569, 95% CI 0.3330.970) in the groups receiving Rebamipide; p=0.038). This effect of Rebamipide deserves special attention and requires additional study, as the result was at the border of statistical significance in the subanalysis of three studies with a large margin of risk reduction in one of them (with the largest sample of patients). Conclusion. The present meta-analysis demonstrated that the Rebamipide addition to H. pylori eradication regimens significantly improves the treatment effectiveness in the Russian patient population.

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.

Extra-Gastroduodenal Manifestation and Helicobacter pyloriInfection

Helicobacter pylori(H. pylori) which are known as Gram-negative bacteria tend to selectively colonize in the gastric epithelium. The infiltration of neutrophilic and mononuclear cells in the antrum and corpus mucosa is one of the consequences of acute and chronic gastritis colonization with H. pylori. This chronic active gastritis is the primary condition related to H. pylori colonization, and other H. pylori-associated disorders result from this chronic inflammatory process. The present study aimed to assess the relationship between H. pylori infection and extra-gastroduodenal manifestations, such as iron deficiency anemia, chronic spontaneous urticarial, diabetes mellitus, and celiac diseases with low ferritin levels. There were 235 subjects aged 3-75 years in the patient's group. The selected eligible patients were subjected to examination by non-invasive methods using stool antigen test and ¹⁴C-urea breath test (¹⁴C-UBT). The H. pylori antigen rapid test cassette (feces) was used for the qualitative detection of H. pylori antigens in human feces specimens. In the present study, 183 (71.8%) patients demonstrated positive results for H. pylori which had been detected by stool antigen test, out of whom 106 (57.9%) and 77 (42.1%) cases were female and male, respectively. The recorded data pointed out that the rates of Iron deficiency anemia, diabetes mellitus, and celiac diseases were 92(50.3%), 62 (33.9%), and 25 (13.7%), respectively. The findings of the present study revealed that H. pylori is more prevalent in females. Moreover, the diagnostic potential of the ¹⁴C UBT method was higher and more accurate than the stool antigen assay.

Rapid and Sensitive Assay of Helicobacter pylori With One-Tube RPA-CRISPR/Cas12 by Portable Array Detector for Visible Analysis of Thermostatic Nucleic Acid Amplification

Helicobacter pylori (H. pylori) has infected more than half of the world’s population and is still a threat to human health. The urea breath test, despite being widely used in clinical diagnosis, still faces huge challenges in the immediate detection of H. pylori. Thus, a rapid, sensitive, and highly specific point of care diagnosis is particularly important for preventing the further transmission of H. pylori and for real-time monitoring of the disease in a given population. Recently, the clustered regularly interspaced short palindromic repeats (CRISPR)-based diagnostics have been applied to various types of nucleic acid testing; however, there are often shortcomings of complex operation and high signal transmission background. In this study, we proposed a new platform for the assay of H. pylori using one-tube-based CRISPR/Cas12a diagnostic methods and designed a detector for this platform, which is a portable array detector for visible analysis of thermostatic nucleic acid amplification (Pad-VATA). By incorporating isothermal recombinase polymerase amplification, our platform could detect the conserved gene fragments of H. pylori with a constant low as 2 copies/μl. The assay process can be performed at a single temperature in about 30 min and integrated into the reactor in the palm-sized Pad-VATA to facilitate rapid diagnosis of H. pylori. We also verified the accuracy of our platform using 10 clinical samples and found that the platform can quickly detect H. pylori infection in a given population. We believe that this fast, convenient, efficient, and inexpensive screening and diagnostic platform can be widely used in various settings, including homes and clinics.

Clinical Evaluation of a Novel Stool Antigen Test Using Bioluminescent Enzyme Immunoassay for Detecting Helicobacter pylori

BACKGROUND

BLEIA ™ "EIKEN" Helicobacter pylori antigen (B[EIA]) is based on the bioluminescent enzyme immunoassay (BLEIA) method that was newly developed with high sensitivity in detecting Helicobacter pylori (H. pylori) antigen in feces.

METHODS

In the project for H. pylori screening and treatment in Saga Prefecture in 2019, 141 students received the stool H. pylori antigen test as a secondary test. For 141 students, a comparative test was conducted between B (EIA) and extracorporeal diagnostic agents that were marketed in Japan as of 2019. The detection performance of H. pylori ATCC43504 standard strain and H. pylori antigen in commercial human fecal specimens were conducted.

RESULTS

The comparison of B (EIA) with Quick Chaser ^TM H. pylori (Q [IC]) revealed positive and negative concordance ratios of B (EIA) to Q (IC) of 100.0% (110/110) and 71.0% (22/31), respectively. A comparative test was conducted between B (EIA) and extracorporeal diagnostic agents that were marketed in Japan as of 2019, and B (EIA) was most sensitive on "detecting H. pylori antigen of ATCC43504 standard strain" and "detecting H. pylori antigen in commercial human fecal specimens," compared with other kits. Nine dissociated specimens that were negative for Q (IC) and positive for B (EIA) were confirmed. The measured value of B (EIA) in the dissociation samples were 1.3-87.4 cutoff index in the range that can be evaluated as negative by other fecal H. pylori antigen test kits, all the dissociation samples were H. pylori antigen-positive cases, and finally the cause of result divergence was presumed as false negative due to insufficient sensitivity of Q (IC).

CONCLUSION

B (EIA) that is based on the BLEIA method, which applies firefly luciferase luminescence, is more sensitive than stool antigen test kits that are currently marketed in Japan and is very useful in diagnosing H. pylori infection, especially in situations where noninvasive tests are preferred, such as in children.

PRE-OPERATIVE SCREENING OF HELICOBACTER PYLORI IN BARIATRIC PATIENTS: IS HISTOPATHOLOGICAL ANALYSIS NECESSARY?

BACKGROUND

Helicobacter pylori infection has been reported to lead to post-operative complications after bariatric surgery (BS), especially marginal ulcers. The optimal method for pre-operative screening is yet to be determined.

OBJECTIVE

To analyze the diagnostic accuracy of the endoscopic urease test for the detection of H. pylori in individuals undergoing BS and the main endoscopic and histological changes within this population.

METHODS

A cross-sectional study was carried out based on a database from medical records of 232 individuals who underwent BS between 2016 and 2019 at a tertiary university hospital. Clinical, anthropometric, and endoscopic data were analyzed. The gold-standard method considered to calculate diagnostic accuracy variables was histopathological examination through hematoxylin-eosin/Giemsa stains.

RESULTS

87.5% of the participants were female; mean age was 38.5±9.5 years and average body mass index was 37.6±3.8 kg/m2. The commonest endoscopic finding was gastritis (50.9%) with a predominance of the mild erosive form (25%). Upon histological examination, 59.1% of the participants had confirmed H. pylori infection. H. pylori infection was associated with higher frequencies of endoscopic duodenitis (23.4% vs 12.6%; P=0.04), histological chronic gastritis (100% vs 56.8%; P<0.0001) and histological acute gastritis (58.4% vs 2.1%; P<0.0001). The urease test had a sensitivity of 79.6% and a specificity of 97.9%, leading to an overall accuracy of 87.1%.

CONCLUSION

The endoscopic urease test is highly accurate for pre-operative screening of H. pylori infection in individuals who undergo BS. H. pylori infection was significantly associated with endoscopic (duodenitis) and histopathological (chronic and active gastritis) changes.

The effectiveness of eradication therapy of the 1st line of Helicobacter pylori infection in patients with type 2 diabetes mellitus

Aim. Evaluation of the efficacy and safety of eradication therapy of infection Helicobacter pylori in patients with H. pylori- associated pathology of the upper gastrointestinal tract and concomitant type 2 diabetes mellitus (DM). Materials and methods. The prospective randomized study involving 180 patients (87 men and 93 women) with H. pylori- associated pathology of the upper gastrointestinal tract was carried out. The patients were divided into four groups of 45 people: 1 patients without diabetes who received the classic triple eradication therapy; 2 patients with type 2 DM who received the classic triple eradication therapy; 3 patients without DM who underwent quadrotherapy with bismuth preparations; 4 patients with type 2 DM who underwent quadrotherapy with bismuth preparations. Eradication therapy was carried out for 14 days. Evaluation of the effectiveness of eradication using a breath test was carried out 4 weeks after completion of the course of treatment. Eradication success was assessed separately for ITT and PP analyzes. Results. The effectiveness of classical triple eradication therapy in patients with concomitant type 2 DM is 64.4% in the ITT group and 69.05% in the PP: quadrotherapy 73.34 and 80.49%, respectively. The effectiveness of first line eradication therapy is higher in patients without DM compared with groups of patients with concomitant type 2 DM: ITT 83.33%, PP 88.23% and ITT 68.89%, PP 74.70%, respectively. The incidence of side effects in patients with type 2 DM: with the use of classical triple therapy 22.23%, quadrotherapy 31.12%. Conclusion. The data of the study of the efficacy and safety of line I eradication therapy make it possible to recommend the four-component therapy based on bismuth for use in clinical practice, especially in patients with DM.