Pylori-positive Status Research Articles

Impact of Helicobacter pylori infection status on outcomes among patients with advanced gastric cancer treated with immune checkpoint inhibitors

BackgroundGut microbiota composition can influence cancer immunotherapy response. Recent evidence suggests Helicobacter pylori infection may reduce immune checkpoint inhibitor (ICI) efficacy in lung cancer and melanoma, but thorough characterization of...

Helicobacter pylori Infection Is Associated With Thyroid Dysfunction in Children With Congenital Hypothyroidism.

Helicobacter pylori (H. pylori) infection leads to a systemic low-grade inflammatory state and has been associated causally with a diverse spectrum of extra-gastric disorders. Among them, the infection has been involved in the pathogenesis of autoimmune thyroid disease (ATD), but only one study had evaluated children. Therefore, a cross-sectional study was conducted in a cohort of 142 children and adolescents, randomly assessed among those followed up for thyroid diseases in a university pediatric endocrinology service: 106 with congenital hypothyroidism (CH) and 36 with ATD. All children were asymptomatic, under strict control on levothyroxine replacement, and reported no other diseases or use of drugs. Helicobacter pylori status was evaluated by the 13C-Urea Breath Test (13C-UBT). Antithyroid antibodies (ATPO, antiTg, and TRAb) and serum thyroid hormones (TSH, free T4, and T3) were assessed by standard assays. Data were analyzed in logistic models by the SPSS statistical software package, and a p-value ≤ 0.05 was considered statistically significant. The prevalence of H. pylori infection was 19.44% in children with ATD. Neither the gender nor the serum levels of thyroid hormones and antithyroid antibodies were associated with the H. pylori-positive status. Thirty-seven (34.90%) children with CH were infected with H. pylori. The mean T3 serum level (3.59 ± 0.84) was significantly lower (p = 0.001) in the infected children than in those free from the infection (3.95 ± 0.89), association that remained after adjustment for the other variables in the multivariate analysis. Because no difference was observed in the levels of TSH and T4, the results indicate that the infection may lead to impairment in the thyroid hormonal balance, but not in the hypothalamic-pituitary-thyroid axis function. In as much as H. pylori infection is highly widespread and the prevalence of CH is also not negligible, additional studies are required to confirm our results and to identify the involved mechanisms.

The Stool Antigen Test is Efficient at Detecting Helicobacter pylori Infection in Bangladeshi Peptic Ulcer Patients

Aims: Helicobacter pylori (H. pylori) is the primary causative agent of peptic ulcers in multiple developing countries, including Bangladesh. This study was designed to investigate the diagnostic value of a rapid immunochromatography-based H. pylori stool antigen (HpSAg) test to screen for H. pylori infection in a Bangladeshi population. Methodology and results: A total of 140 suspected peptic ulcer patients who underwent an upper gastrointestinal endoscopy at Chittagong Medical College and Hospital, Chattogram, Bangladesh were included in the study. A histopathology, rapid urease test (RUT), and microscopic examination of the stained smears were conducted to define the H. pylori-positive cases. Later, a stool antigen detection test was performed for the H. pylori-positive status group, the H. pylori-negative status group, the indeterminate status group, and the healthy controls. Out of the 140 suspected peptic ulcer patients, 75 (53.6%) patients were confirmed to have peptic ulcers or erosions. Although the proportion of antral erosion was 57.4% in patients who were under 40 years old, it decreased to 23.4% in patients over 40 years old. Patients over 40 years of age mostly suffered from pyloric erosion (42.9%). All peptic ulcer patients were also positive according to the histopathological analysis. However, microscopic grading of the curved bacilli and RUT were found among 93.3% (70/75) and 89.3% (67/75) patients who were positive, respectively. In our study, high sensitivity (95%), specificity (80%), and diagnostic accuracy (91%) scores for the HpSAg assay were obtained. Conclusions, significance, and impact of the studies: The HpSAg test, as a comparatively less sophisticated assay, can be efficient at detecting the presence of H. pylori pre- and post-therapy, and it provides more valid test results than other invasive test methods.

Expression of HOTAIR and MEG3 are negatively associated with H. pylori positive status in gastric cancer patients.

Background: Chronic infection with Helicobacter pylori is one of the main causes of gastric cancer (GC). Besides, lncRNAs play crucial roles in cancer pathobiology including GC. Here we aimed to investigate the expression of MEG3 and HOTAIR in gastric cancer tissues and evaluate their association with the H. pylori status.Materials and Methods: One hundred samples were obtained. Total RNA was extracted, cDNA was synthesized and expression of MEG3 and HOTAIR was assessed using qRT-PCR. Association of their expression with H. pylori status and other clinicopathological characteristics were investigated. Furthermore, sensitivity and specificity of the MEG3 and HOTAIR expression levels for discrimination of the tumor and non-tumor samples were evaluated by Receiver operating characteristic (ROC) curve analysis.Results: We observed upregulation of HOTAIR but downregulation of MEG3 in tumor compared to the non-tumor tissues. We also found a significant negative association between their expression levels and H. pylori positive status. However, only the expression level of HOTAIR was significantly associated with the size and stage of the tumor (P < 0.05). The ROC curve analysis revealed that the expression levels of MEG3 and HOTAIR might discriminate GC tumor and non-tumor tissues.Conclusions: In conclusion, this study revealed a negative association between H. pylori infection and expression of MEG3 and HOTAIR. The results suggested that the expression level of these lncRNAs might be considered as potential biomarkers for GC.

Association between regular arrangement of collecting venules and Helicobacter pylori status in routine endoscopy

BackgroundThe sensitivity of regular arrangement of collecting venules (RAC)-positive pattern for predicting Helicobacter pylori (H. pylori)-negative status greatly altered from 93.8 to 48.0% in recent two decades of various studies, while the reason behind it remained obscure. The aim of this study was to investigate the value of RAC as an endoscopic feature for judging H. pylori status in routine endoscopy and reviewed the underlying mechanism.MethodsA prospective study with high-definition non-magnifying endoscopy was performed. RAC-positive and RAC-negative patients were classified according to the collecting venules morphology of the lesser curvature in gastric corpus. Gastric biopsy specimens were obtained from the lesser and greater curvature of corpus with normal RAC-positive or abnormal RAC-negative mucosal patterns. Helicobacter pylori status was established by hematoxylin and eosin staining and immunohistochemistry.Results41 RAC-positive and 124 RAC-negative patients were enrolled from June 2020 to September 2020. The prevalence of H. pylori infection in patients with RAC-positive pattern and RAC-negative pattern was 7.3% (3/41) and 71.0% (88/124), respectively. Among all 124 RAC-negative patients, 36 (29.0%) patients were H. pylori-negative status. Ten patients (32.3%) demonstrated RAC-positive pattern in 31 H. pylori-eradicated cases. The sensitivity, specificity, positive predictive value, and negative predictive value of RAC-positive pattern for predicting H. pylori-negative status were 51.4% (95% CI, 0.395–0.630), 96.7% (95% CI, 0.900–0.991), 92.7% (95% CI, 0.790–0.981), and 71.0% (95% CI, 0.620–0.786), respectively.ConclusionsRAC presence can accurately rule out H. pylori infection of gastric corpus, and H. pylori-positive status cannot be predicted only by RAC absence in routine endoscopy.Trial registration The present study is a non-interventional trial.

Synergism of factors contributing to the development of gastric development of gastric ulcer and gastric cancer

Aimto study to compare the factors contributing to the development of gastric ulcer and gastric cancer in the population of the Republic of Khakassia. Materials and methods. Epidemiological screening of the ulcer was carried out by the simultaneous transverse method (n = 4217) using endoscopy, morphological, rapid urease, serological and PCR for biopsy testing of H. pylori. Patients were selected by 25% random sampling. Retrospectively investigated the epidemiological parameters of the GC (2295 patients) 2002-2017. Risk factors were studied by questioning patients with a newly established diagnosis (2018-2019). Results. The prevalence of ulcer was 8.9% in Caucasians and 4.5% in Khakasses, p <0.001. The incidence of pancreatic cancer in men is 2 and 1.28 times higher than in women, respectively. With age, the incidence of ulcer and cancer increased. The association of H. pylori with peptic ulcer is registered in both populations. Among patients with gastric cancer, 78% of respondents had H. pylori-positive status, 18% of patients had a combination with peptic ulcer. Tobacco smoking had a pronounced direct relationship with ulcerogenesis. The incidence of peptic ulcer in smokers of more than 10 packs/year of Caucasians was 17.0%, Khakasses - 17.2%, p <0.001. Among patients with gastric cancer, the fact of smoking was found in 45% of respondents; the proportion of men is 3 times more than women. Conclusion In the population of the Republic of Khakassia, conventional risk factors for peptic ulcers, such as male gender, increasing age, tobacco smoking, and H. pylori infection, are also predictors of the development of stomach cancer

Correlation between Gastric Mucosal Morphologic Patterns and Histopathological Severity of Helicobacter pylori Associated Gastritis Using Conventional Narrow Band Imaging Gastroscopy.

Background and Aim. Identifying specific gastric mucosal morphologic patterns useful for detecting Helicobacter pylori associated gastritis and correlation with histopathological severity. Methods. The endoscopists classified the C-NBI gastroscopic findings into 5 gastric mucosal morphologic patterns as follows: type 1: regular arrangement of collecting venules, type 2: cone-shaped gastric pits, type 3: rod-shaped gastric pits with prominent sulci, type 4: ground glass-like morphology, and type 5: dark brown patches with bluish margin and irregular border. Biopsies of all of the cases were then evaluated by 5 pathologists for definitive Helicobacter pylori diagnosis. Result. Type 1 and type 2 patterns were statistically significant in predicting Helicobacter pylori negative status (58/60, P < 0.01). Type 3, type 4, and type 5 patterns were statistically significant in predicting Helicobacter pylori positive status (132/140, P < 0.01). Furthermore, the sensitivity, specificity, and positive and negative predictive values of type 3, 4, or 5 morphologies for predicting Helicobacter pylori positive were 94.28%, 96.66%, 98.50%, and 87.87%, respectively, correlated well with inflammation grading according to the Sydney classification (P < 0.01). Conclusion. Our study suggests that gastric mucosal morphologic patterns in the Helicobacter pylori infected gastric mucosa can be reliably identified using C-NBI gastroscopy with good correlation with inflammation grading.

Particularities of gastroduodenal pathology in children, associated with cytotoxic CAGA-positive strains of Helicobacter pylori.

The aim of the study was to investigate the characteristics of inflammatory gastroduodenal diseases in children, associated with CagA-positive strains of H. pylori. We observed 283 children aged 7 to 17 years with chronic gastroduodenal pathology in exacerbation stage; endoscopic examination of the esophagus, stomach and duodenum was performed, total Ig M, A, G to Ag SagA H. pylori protein in blood serum by ELISA was determined. The study group included 156 patients infected with cytotoxic CagA (+) strains of H. pylori (H. pylori-positive status), comparison group - 59 (20,9%) patients with H. pylori-negative status. It was shown that 55.1% of patients observed were infected with cytotoxic CagA (+) strains of H. pylori. The intensity of clinical symptoms and the severity of inflammatory changes in stomach and duodenum mucosa in children with H. pylori infection is associated with cytotoxic strains of CAG A H. pylori. Presence of extensive gastritis (34,6%; p<0,05), lymphoid hyperplasia (16,0%; p <0,05), turbid mucus in the gastric lumen are the special features of endoscopic changes in children with H. pylori-positive status.

PARP1 Polymorphisms Increase the Risk of Gastric Cancer in a Chinese Population

Poly(adenosine diphosphate [ADP]-ribose) polymerase 1 (PARP1), a protein involved in the DNA repair mechanism, plays an important role in carcinogenesis. In this study, we investigated whether single nucleotide polymorphisms of PARP1 contribute to gastric cancer (GC) and its precursor lesions (gastric precancerous lesions; GPL) in a case-control study conducted in the Hexi area of China, a high-risk area for GC. PARP1 162C>G (Phe54Leu) and 2819A>G (Lys940Arg) polymorphisms were genotyped by real-time PCR using a TaqMan assay in 140 GC cases, 110 GPL cases, and 120 controls. Data were statistically analyzed using the chi-squared test and a logistic regression model. The presence of the PARP1 2819G allele was associated with an increased risk of GC (odds ratio [OR] 2.354; 95% CI 1.140, 4.861; p = 0.018), especially for cardia GC and diffuse-type GC (ORs 2.988 and 3.784, respectively). We also observed an interaction between Helicobacter pylori infection, GC family history, and the presence of the PARP1 2819G allele. In contrast, the PARP1 162C>G polymorphism was not significantly associated with GPL or GC. The study suggests that the PARP1 2819G allele is associated with an increased risk of GC. In addition, H. pylori-positive status and family history jointly contribute to a higher risk of GC.

Helicobacter pylori infection as an independent prognostic factor for locally advanced gastric cancer patients treated with adjuvant chemotherapy after curative resection

A few studies reported the association between negative Helicobacter pylori infection and poor clinical outcome in resected gastric cancer patients. We investigated the H. pylori infection status and its association with the clinical outcome in 274 locally advanced gastric cancer patients (American Joint Committee on Cancer stage IB: 25, II: 82, IIIA: 80, IIIB: 39 and IV: 48) who underwent adjuvant chemotherapy after curative resection (≥ D2 dissection). H. pylori infection status in hematoxylin and eosin stained corporal and antral mucosa of non-tumor tissue was graded according to the updated Sydney System and categorized as H. pylori negative (normal or mild infection) and H. pylori positive (moderate or marked infection). Eighty-one patients received 5-fluorouracil (5-FU) and doxorubicin-based chemotherapy, while 193 patients underwent 5-FU, mitomycin-C and polysaccharide-K chemotherapy. The median follow-up duration of survivors was 144 (120-184) months. In univariate analysis, patients with H. pylori negative status (108 patients) demonstrated significantly poor 10-year overall survival (OS) compared to those with H. pylori-positive status (166 patients; 21.3% vs. 71.1%, p < 0.0001). H. pylori negative status was associated with poor outcome in all stages except stage IIIB. In multivariate analysis, H. pylori-negative status was the most significant independent prognostic factor of poor OS (hazard ratio: 3.45, 95% confidence interval: 2.43-4.89, p < 0.0001) followed by old age (>54 years, p < 0.0001), advanced stage (stage III or IV, p = 0.001), and Borrmann type IV (p = 0.027). H. pylori infection status seems to have strong prognostic significance in locally advanced gastric cancer. H. pylori-negative patients may need careful follow-up after curative resection.

A New Cyclo-Oxygenase-2 Gene Variant in the Han Chinese Population is Associated with an Increased Risk of Gastric Carcinoma

Cyclo-oxygenase-2 (COX-2, also known as prostaglandin synthase 2) influences carcinogenesis through regulation of angiogenesis, apoptosis, and cytokine expression. COX-2 is encoded by the gene PTGS2. Several studies have suggested that PTGS2 single-nucleotide polymorphisms (SNPs) are involved in gastrointestinal carcinogenesis. In this study, we observed the PTGS2 Val511Ala (5939T/C) polymorphism in the Chinese population for the first time, and investigated whether this polymorphism might contribute to gastric cancer in a case-control study conducted in the Gansu province of China, a high-risk area for gastric cancer. We determined the genotypes of 110 gastric cancer patients and 138 controls using polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) analysis. Data were statistically analyzed using a chi-squared test and a logistic regression model. In our analysis, PTGS2 5939C allele carriers were at increased risk of gastric cancer (odds ratio [OR] 1.742; 95% confidence interval [CI] 1.009, 3.005; p = 0.045). We also found an interaction between Helicobacter pylori infection, a family history of gastric cancer, and presence of the 5939C allele. This study further indicated that H. pylori-positive status and family history jointly contribute to a higher risk of gastric cancer.

Mucosal patterns ofHelicobacter pylori-related gastritis without atrophy in the gastric corpus using standard endoscopy

To identify the mucosal patterns of Helicobacter pylori (H. pylori)-related gastritis in the gastric corpus using standard endoscopy and to evaluate their reproducibility. A total of 112 consecutive patients underwent upper gastrointestinal endoscopy. The endoscopists classified the endoscopic findings into 4 patterns. In the second part of the study, 90 images were shown to 3 endoscopists in order to evaluate the inter-observer and intra-observer variability in image assessment. The mucosal patterns of the gastric body were categorized into 4 types. Type 1 pattern was defined as cleft-like appearance, type 2 as regular arrangement of red dots, type 3 pattern as the mosaic mucosal pattern and type 4 pattern as the mosaic pattern with a focal area of hyperemia. Type 1 and type 2 mucosal patterns were statistically significant in predicting H. pylori-negative status as compared with other mucosal types (chi(2) = 12.79 and 61.25 respectively, P < 0.01). Type 3 and type 4 mucosal patterns were statistically significant in predicting a H. pylori-positive status as compared with other mucosal types (chi(2) = 21.22 and 11.02 respectively, P < 0.01). Furthermore, the sensitivity, specificity, positive and negative predictive values of type 3 plus type 4 patterns for predicting H. pylori-positive gastric mucosa were 100%, 86%, 94%, and 100%, respectively. The mean kappa values for inter- and intra-observer agreement in assessing the various endoscopic patterns were 0.808 (95% CI, 0.678-0.938) and 0.826 (95% CI, 0.727-0.925) respectively. Our study suggests that mucosal patterns in H. pylori-infected gastric mucosa without atrophy can be reliably identified using standard endoscopy in the gastric corpus.

Evaluation of a Novel Stool Native Catalase Antigen Test for Helicobacter pylori Infection in Asymptomatic North American Children

Rapid immunochromatographic tests for Helicobacter pylori infection have been developed to allow "near-patient" testing. We therefore performed a pilot study to test a rapid immunochromatographic stool antigen test for the diagnosis of H. pylori infection in asymptomatic children. We tested stool specimens collected from children participating in a cohort study in the United States and Mexico. H. pylori-positive status was defined by positivity on at least 2 tests: a commercial H. pylori stool antigen enzyme immunoassay, an immunoglobulin G antibody enzyme immunoassay, and the C-urea breath test. Negative H. pylori status was defined by negative findings of all of these tests. Of 52 children (22 girls, 30 boys) 25 were H. pylori-positive, 19 H. pylori-negative, and 8 uncertain (eg, presumably negative; positive findings on 1 of the 3 noninvasive tests). The sensitivity and specificity of the new stool antigen test for those with definite H. pylori status were 100% (exact 95% CI 86.3%-100% and 82.4%-100%, respectively). This rapid stool antigen test may prove useful for point-of-care testing and epidemiological field studies. Larger prospective studies are needed in symptomatic and asymptomatic children for more precise estimates.

Association Between Helicobacter pylori Infection and Cirrhosis in Patients with Chronic Hepatitis C Virus

We evaluated, employing a logistic regression model, the association between Helicobacter pylori infection and cirrhosis in a cohort of 106 patients (57 males; mean age, 52.9 years; range, 20-78 years) with chronic hepatitis C virus (HCV) from Rosario, Argentina. HCV was confirmed by ELISA and PCR. H. pylori status was determined by ELISA. Of the 106 patients evaluated, 47 (44.3%) had cirrhosis. A total of 70.2% (33/47) of cirrhotic patients and 47.5% (28/59) of noncirrhotic patients were H. pylori-positive. In univariate analyses, cirrhosis was associated with age (P = 0.016) and H. pylori-positive status (P = 0.019) but not with gender (P = 0.28) or length of infection (P = 0.35). In multivariate analysis, H. pylori infection (P = 0.037; OR = 2.42; 95% CI = 1.06-5.53) and age (P = 0.033; OR = 1.04; 95% CI = 1.00-1.07) of patients remained significant and independently associated with cirrhosis. In conclusion, our results demonstrate an association between H. pylori infection and cirrhosis in patients with hepatitis C virus.

Helicobacter pylori and gastrointestinal symptoms in school children in Russia.

Helicobacter pylori is considered to be the major cause of chronic gastritis and duodenal ulcer disease recurrence in childhood. However, the association between H. pylori and recurrent abdominal pain (RAP) syndrome is still controversial. Therefore, the spectrum of clinical variants of gastrointestinal symptoms associated with H. pylori-positive status was studied in consecutive symptomatic children who were undergoing diagnostic endoscopy. A consecutive series of 225 school children from the Ural area of Russia (mean age 11.1 + 1.4 years, age range 7-15 years) who presented with RAP were investigated using esophagogastroduodenoscopy, including three antral biopsies for histology and polymerase chain reaction. Helicobacter pylori immunoglobulin G antibodies were found using a second-generation enzyme immunoassay. Information about the clinical symptoms was collected using a special questionnaire. The authors found a high incidence of H. pylori infection (80%) and peptic ulcers (16%) in 225 school children from the Ural area of Russia who were referred for upper gastrointestinal (UGI) endoscopy for chronic abdominal pain. Of the overall 225 symptomatic children who underwent endoscopy, 182 (80,8%) were found to be H. pylori-positive. Duodenal ulcers were detected in 36 H. pylori-positive children. A family history of peptic ulcers was significantly more frequent in the children infected with H. pylori (P < 0.001). Symptom score and duration of symptoms were similar, but night-time pain (P < 0.0001) and fasting pain relieved by food (P < 0.001) were more frequent in the H. pylori-positive children as compared with the H. pylori-negative children. The present results provide further evidence for a significant association between H. pylori and some patterns of gastrointestinal symptoms in children who underwent UGI endoscopy in order to exclude an organic cause of severe chronic gastrointestinal disorders.

Determination of Helicobacter pylori vacA allelic types by single-step multiplex PCR

To develop and evaluate a novel multiplex PCR assay that enables definition of Helicobacter pylori vacA allelic type in a single reaction. Application of the one-step system to DNA extracts from 22 cultures of known vacA genotype demonstrated that it was highly accurate. Analysis of 15 matched gastric biopsy/culture pairs generated exactly correlating genotype profiles. vacA genotypes were determined from an additional 62/70 gastric biopsies from dyspeptic patients of known H. pylori positive status by the one-step assay, compared with 63/70 by the original two-reaction test. Types s1/m1, s1/m2 and s2/m2 were identified in 51.9%, 31.2% and 16.9% of biopsies, respectively. The multiplex PCR system developed enables rapid one-step vacA genotyping that is accurate, easy to interpret and more economical than the alternative multiple-reaction tests. Application of this system to gastric biopsies from patients in South-east England demonstrated that s1/m1 was the most common genotype, while s1/m2 and s2/m2 were less prevalent. This simple one-step system can be applied direct to antral gastric biopsies without the need for culture, thereby facilitating rapid surveillance of vacA genotype in relation to geographical location and disease status.