Improved Detection of Helicobacter pylori Infection and Premalignant Gastric Mucosa Using "Site Specific Biopsy": a Randomized Control Clinical Trial

UTILITY OF ENDOSCOPIC NARROW-BAND IMAGING FOR IDENTIFYING H. PYLORI-ASSOCIATED GASTRITIS IN CHILDREN

BACKGROUND

Conventional white light endoscopic (WLE) findings of H. pylori-associated gastritis are often non-specific and may not correlate with histology. Narrow band imaging (NBI), an optical digital technique employed for the visualization of vessels and patterns of gastric mucosa may improve identification. We evaluated the role of NBI in detecting H. pylori-associated gastritis and classifying its severity.

METHODS

Institution-based prospective observational study conducted between May 2021-October 2022. Children presenting with chronic abdominal pain (>1-month duration) were evaluated. Eligible children underwent gastroscopy with NBI and gastric biopsies for rapid urease test and histopathology. NBI gastroscopic findings were classified into five grades as per the classification by Alboudy et al. The association of NBI grade with the presence and severity of H. pylori gastritis on histopathology was analysed.

RESULTS

Ninety children (mean age 12.65±3.91 years), 52 (57.7%) males with median duration of symptoms of 4.5 (3-12) months underwent gastroscopy. H. pylori was detected on histopathology in 29 (32%) patients. NBI findings suggested a mucosal abnormality in 27/29 (93.1%) children with H. pylori on histopathology. H. pylori positive gastritis was significantly more common among those with higher (≥3) NBI grades as compared to those with lower NBI grades (61% vs10%, P<0.001). No significant association was found between NBI grade and the severity of H. pylori gastritis (P=0.75). NBI exhibited better sensitivity (0.82) compared to WLE (0.55) in identifying H. pylori-associated gastritis. On receiver operating characteristic curve analysis, NBI had higher area under curve (0.79 vs 0.65) as compared to WLE.

CONCLUSION

NBI morphological pattern is a useful tool in identifying patients with H. pylori-associated gastritis.

Relationship between Helicobacter pylori virulence genes and gastroduodenal disease

OBJECTIVE

This study aimed to identify Helicobacter pylori virulence factors and examine their associations with clinical outcomes in Thai patients. Moreover, the association between these genotypes and gastric mucosa morphological patterns was investigated.

METHODS

This retrospective study enrolled patients who underwent esophagogastroduodenoscopy at Suranaree University of Technology Hospital. The presence of the cagA and vacA genes was investigated by real-time polymerase chain reaction.

RESULTS

The H. pylori-specific genes ureA and 16S rRNA were detected in all 698 gastric biopsy specimens. In total, 567 (81.23%) patients with H. pylori infection were positive for the cagA gene, 443 (63.46%) were positive for the vacA gene, and 370 (53.0%) were positive for both. The cagA genotype was significantly more common in patients with chronic gastritis and peptic ulcers (78.99% and 79.41%, respectively) than the vacA gene (51.48% and 55.88%, respectively) and combined genotypes (32.34% and 47.05%, respectively). Moreover, the cagA genotype was significantly more common in patients with type 4 or 5 gastric mucosa patterns (69.49% and 76.31%, respectively).

CONCLUSIONS

The cagA genotype is the main cause of serious inflammation of the gastric mucosa. The cagA gene is possibly an important factor explaining gastroduodenal disease outcomes in Thai patients with H. pylori infection.

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.

Endoscopic and histopathological findings in adult dyspeptic patients, and their association with Helicobacter pylori infection in Dhaka, Bangladesh

OBJECTIVES

Conventional upper-intestinal endoscopy is usually performed to diagnose Helicobacter pylori (H. pylori) associated diseases, using gastric mucosa from the biopsy. The objective of our study was to identify the prevalence of H. pylori and its relation with endoscopic findings and histopathological features in dyspeptic adult patients.

METHODS

Gastroduodenal biopsy specimens were collected from 143 adult dyspeptic outpatients who attended the Department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University (BSMMU) and Dhaka Medical College Hospital (DMCH), for endoscopy. H. pylori was identified by rapid urease test (RUT), ureC gene PCR, and histological staining (Giemsa).

RESULTS

The study population was divided into H. pylori-positive cases (47; 32.9%) and H. pylori-negative cases (96; 67.1%), based on the case definitions used in the study. The highest rate of H. pylori infection was found in the 41-50 years age group (25.5%). Endoscopically, 101 (97.1%) dyspeptic patients had gastritis, with the majority of H. pylori infections found among histopathologically diagnosed duodenal ulcer patients. Endoscopic findings were significantly correlated with histological findings (p < 0.001).

CONCLUSION

Significant correlations between endoscopic and histopathological findings were observed. Early detection and prompt treatment of H. pylori infection are essential for the prevention of serious complications.

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.

The endoscopic predictors of Helicobacter pylori status: a meta-analysis of diagnostic performance

Objective:

The endoscopic findings associated with Helicobacter pylori–naïve status, current infection or past infection are an area of ongoing interest. Previous studies have investigated parameters with a potential diagnostic value. The aim of this study was to perform meta-analysis of the available literature to validate the diagnostic accuracy of mucosal features proposed in the Kyoto classification.

Data sources:

The databases of MEDLINE and Embase, clinicalTrials.gov and the Cochrane Library were systematically searched for relevant studies from October 1999 to October 2019.

Methods:

A bivariate random effects model was used to produce pooled diagnostic accuracy calculations for each of the studied endoscopic findings. Diagnostic odds ratios and sensitivity and specificity characteristics were calculated to identify significant predictors of H pylori status.

Results:

Meta-analysis included 4380 patients in 15 studies. The most significant predictor of an H pylori-naïve status was a regular arrangement of collecting venules (diagnostic odds ratio 55.0, sensitivity 78.3%, specificity 93.8%). Predictors of active H pylori infection were mucosal oedema (18.1, 63.7%, 91.1%) and diffuse redness (14.4, 66.5%, 89.0%). Map-like redness had high specificity for previous H pylori eradication (99.0%), but poor specificity (13.0%).

Conclusion:

The regular arrangement of collecting venules, mucosal oedema, diffuse redness and map-like redness are important endoscopic findings for determining H pylori status. This meta-analysis provides a tentative basis for developing future endoscopic classification systems.

Precancerous Gastric Lesions with Helicobacter pylori vacA +/babA2+/oipA + Genotype Increase the Risk of Gastric Cancer

Objective

The clinical outcomes of gastric diseases such as chronic gastritis, peptic ulcer, and gastric cancer have been attributed to the interplay of virulence factors of Helicobacter pylori (H. pylori), host genetic susceptibility, and host immune responses. This study investigated the presence of cagA, vacA, iceA2, babA2, and oipA genes and their association with clinical outcomes.

Methods

Chronic gastritis, atrophic gastritis, and intestinal metaplasia specimens were obtained from patients who underwent endoscopy and surgical resection between January 2017 and December 2018; specimens from gastric cancer patients treated between January 2014 and December 2018 were also added. H. pylori), host genetic susceptibility, and host immune responses. This study investigated the presence of cagA, vacA, iceA2, babA2, and oipA genes and their association with clinical outcomes. H. pylori), host genetic susceptibility, and host immune responses. This study investigated the presence of

Results

H. pylori), host genetic susceptibility, and host immune responses. This study investigated the presence of vacA, babA2, and oipA genes and their association with clinical outcomes. vacA, babA2, and oipA genes and their association with clinical outcomes. P=0.033, OR = 2.64; 95% CI = 1.44–4.82, P=0.033, OR = 2.64; 95% CI = 1.44–4.82, P=0.033, OR = 2.64; 95% CI = 1.44–4.82, H. pylori vacA⁺/babA2, and oipA genes and their association with clinical outcomes. P=0.033, OR = 2.64; 95% CI = 1.44–4.82,

Conclusion

In this present study, we reported on the virulence genes of H. pylori infection to reveal their association with increased risk of chronic gastritis, precancerous gastric lesions, and gastric cancer. Precancerous gastric lesions with H. pylori vacA+/babA2+/oipA+ genotype increased the risk of gastric cancer.H. pylori), host genetic susceptibility, and host immune responses. This study investigated the presence of H. pylori vacA⁺/babA2, and oipA genes and their association with clinical outcomes.

A systematic review of the role of non-magnified endoscopy for the assessment of H. pylori infection

Background and study aims  There is growing interest in the endoscopic recognition of Helicobacter pylori infection, and application to routine practice. We present a systematic review of the current literature regarding diagnosis of H. pylori during standard (non-magnified) endoscopy, including adjuncts such as image enhancement and computer-aided diagnosis. Method  The Medline and Cochrane databases were searched for studies investigating performance of non-magnified optical diagnosis for H. pylori , or those which characterized mucosal features associated with H. pylori infection. Studies were preferred with a validated reference test as the comparator, although they were included if at least one validated reference test was used. Results  Twenty suitable studies were identified and included for analysis. In total, 4,703 patients underwent investigation including white light endoscopy, narrow band imaging, i-scan, blue-laser imaging, and computer-aided diagnostic techniques. The endoscopic features of H. pylori infection observed using each modality are discussed and diagnostic accuracies reported. The regular arrangement of collecting venules (RAC) is an important predictor of the H. pylori -naïve stomach. "Mosaic" and "mottled" patterns have a positive association with H. pylori infection. The "cracked" pattern may be a predictor of an H. pylori- negative stomach following eradication. Conclusions  This review summarizes current progress made in endoscopic diagnosis of H. pylori infection. At present there is no single diagnostic approach that provides validated diagnostic accuracy. Further prospective studies are required, as is development of a validated classification system. Early studies in computer-aided diagnosis suggest potential for a high level of accuracy but real-time results are awaited.

Toll-like receptor 2 and 4 polymorphisms associated with Helicobacter pylori susceptibility and gastric cancer

BACKGROUND/AIMS

Genetic polymorphisms in Toll-like receptors (TLRs) are important influence on gastric lesion development and Helicobacter pylori susceptibility.

MATERIALS AND METHODS

TLR2 rs3804099 and rs3804100 and TLR4 rs10759932 were determined in a total of 400 patients. The association among genotypes and the risk of gastric lesion development and H. pylori susceptibility were evaluated by the odds ratios (ORs) and 95% confidence intervals (95% CIs) from logistic regression analyses.

RESULTS

TLR4 rs10759932, C/C homozygous genotype was associated with an increased risk of premalignant/malignant (OR=2.48, 95% CI=1.96-4.62, p=0.015). The recessive model of TLR4 rs10759932 showed a decreased risk of H. pylori susceptibility (adjusted OR=0.52, 95% CI=0.38-0.82, p=0.046). Meanwhile, the recessive model was associated with an increased risk of non-malignant (OR=3.46, 95% CI=2.25-5.67, p=0.001). In subjects with H. pylori infection, the recessive model was associated with an increased risk of non-malignant (OR=2.28, 95% CI=1.24-3.57, p=0.001) and premalignant/malignant (OR=1.83, 95% CI=1.16-2.84, p=0.027).

CONCLUSION

TLR4 rs10759932, but not TLR2 rs3804099 and rs3804100, was associated with risk of premalignant and/or malignant and H. pylori susceptibility. H. pylori infection seems to contribute to chronic gastritis, and premalignant/malignant supported the development of the premalignant/malignant lesions involved in H. pylori infection that is critical to gastric cancer in Thai patients.

Role of screening colonoscopy for colorectal tumors in Helicobacter pylori-related chronic gastritis with MDM2 SNP309 G/G homozygous: A prospective cross-sectional study in Thailand

BACKGROUND/AIMS

Helicobacter pylori infection is a risk factor for gastric cancer and colorectal cancer (CRC). MDM2 SNP309 G/G homozygosity is known to be the genetic background that influences the severity of inflammation in the gastric mucosa, and it corresponds to CRC development. We examined the role of screening colonoscopy in H. pylori-related chronic gastritis and the association of patients who have MDM2 SNP309 G/G homozygosity and advanced colorectal neoplasia (CRN) susceptibility.

MATERIALS AND METHODS

A prospective cross-sectional study was used to investigate H. pylori-related gastritis in 331 consecutive asymptomatic patients who had MDM2 SNP309 G/G homozygosity and who were enrolled from November 2014 to July 2017. The MDM2 SNP309 polymorphism was genotyped by real-time PCR hybridization probe assay.

RESULTS

Totally, there were 331 patients with H. pylori-related gastritis, of whom 39 (8.76%) had advanced CRN. The H. pylori-positive group comprised 180 patients (54.36%). H. pylori infection was associated with advanced CRN (OR: 2.09, 95% CI: 1.56-2.80; p=0.01) and had an increased risk of advanced CRN (OR: 4.24, 95% CI: 1.76-5.21; p=0.01) after adjusting for confounding factors. Patients with H. pylori infection had a significantly increased risk of high-grade dysplasia or invasive adenocarcinoma (OR: 2.96, 95% CI: 1.48-4.17; p=0.03).

CONCLUSION

Chronic gastritis patients infected with H. pylori and who had MDM2 SNP309 G/G homozygosity had an increased risk of advanced CRN, particularly high-grade dysplasia including invasive adenocarcinoma. Screening colonoscopy in these patients might benefit colorectal polyp diagnosis and prevention and early CRC treatment in the Thai population.

Effects of periodontal therapy on eradication and recurrence of Helicobacter pylori infection after successful treatment

OBJECTIVES

This study aimed to evaluate the effects of periodontal therapy on the efficacy of Helicobacter pylori eradication and on the recurrence of infection after eradication.

METHODS

We conducted a prospective randomized trial on 698 gastric H. pylori-infected patients, of whom 347 received gastric H. pylori treatment alone and 342 received gastric H. pylori treatment plus periodontal therapy. The presence of H. pylori and associated virulence genes were detected by real-time polymerase chain reaction.

RESULTS

After eradication of gastric H. pylori infection, the recurrence of gastric H. pylori was significantly lower in the gastric H. pylori treatment plus periodontal therapy group than in the group receiving gastric H. pylori treatment alone (OR 0.67; 95% CI 0.45 to 0.99), whereas the eradication rate was not significantly different (OR 0.87; 95% CI 0.68 to 0.98). There was a close relationship between the presence of H. pylori in saliva and its presence in the stomach.

CONCLUSIONS

The oral cavity is an important reservoir for gastric H. pylori infection. Adjunctive periodontal therapy could enhance the efficiency of H. pylori treatment and reduce the recurrence of gastric H. pylori infection.

Expression of Cancer Stem Cell Marker CD44 and Its Polymorphisms in Patients with Chronic Gastritis, Precancerous Gastric Lesion, and Gastric Cancer: A Cross-Sectional Multicenter Study in Thailand

Here we investigated CD44 protein expression and its polymorphisms in patients with chronic gastritis, precancerous gastric lesions, and gastric cancer; and we evaluated our result with the risk of CD44 protein expression and clinicopathological characteristics. Our results obtained by analyzing 162 gastric cancer patients, 125 chronic gastritis, and 165 precancerous gastric lesions from three study centers in Thailand showed that CD44 expression was significantly higher in patients with precancerous gastric lesions and gastric cancer while patients with chronic gastritis were negative for CD44 staining (p = 0.036). We further observed the significant association of variant genotype; gastric cancer patients carrying AG or GG of CD44 rs187116 had more increased risk of CD44 expression than wild-type (WT) carriers (AG: odds ratio (OR) = 5.67; 95% CI = 1.57-7.23; p = 0.024 and GG: OR = 8.32; 95% CI = 2.94-11.42; p = 0.016), but no significant difference in the risk of CD44 expression due to polymorphism in patients with precancerous gastric lesions. Our results suggested that CD44 expression could be used as a marker for the prediction of gastric cancer development, particularly in patients with precancerous gastric lesions carrying AG or GG, who were selected to surveillance follow-up for gastric cancer prevention.

Advanced endoscopic imaging in gastric neoplasia and preneoplasia

Conventional white light endoscopy remains the current standard in routine clinical practice for early detection of gastric cancer. However, it may not accurately diagnose preneoplastic gastric lesions. The technological advancements in the field of endoscopic imaging for gastric lesions are fast growing. This article reviews currently available advanced endoscopic imaging modalities, in particular chromoendoscopy, narrow band imaging and confocal laser endomicroscopy, and their corresponding evidence shown to improve diagnosis of preneoplastic gastric lesions. Raman spectrometry and polarimetry are also introduced as promising emerging technologies.

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

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

Diagnostic of Helicobacter pylori infection

There is progress in endoscopy techniques. While it is not yet possible to detect Helicobacter pylori directly in the stomach, it becomes easier to detect the mucosal changes induced by the bacteria. Some small changes can also increase the sensitivity of the invasive tests, for example culture or histology, but the wide use of proton-pump inhibitors has a negative impact on these tests. Only molecular methods are able to detect a limited load of bacteria, especially by using real-time PCR but also with new methods, for example dual-priming oligonucleotide-based PCR, loop-medicated isothermal amplification, droplet-digital PCR or a multiple genetic analysis system. Among the noninvasive tests, urea breath test remains a test of major interest, while there are attempts to develop an ammonia breath test and other nanosensor devices. A new antigen stool test, a chemoluminescence immunoassay using the LIAISON apparatus has also been tested for the first time with success. Despite its limitations, serology remains the most popular test to detect H. pylori antibodies. It also allows pepsinogen dosage which is of interest for detecting atrophy.