Histological identification of Helicobacter pylori: comparison of staining methods

Utilization of an Automated Latex Agglutination Turbidity Assay for Assessing Gastric Mucosal Alteration during Helicobacter pylori Infection

Background/Aims

: A latex agglutination turbidity (LA) assay to test for serum antibodies has been approved in Japan and Korea for mass screening of Helicobacter pylori infection. In this study, we evaluated the LA assay for diagnosing H. pylori infection and predicting gastric mucosal changes in a Mongolian population.

Methods

: In total, 484 individuals were classified into H. pylori-positive (n=356) and H. pylori-negative (n=128) groups, as determined by histology and H. pylori culture.

Results

: The best cutoff, sensitivity, and specificity values for the LA assay were 18.35 U/mL, 74.2%, and 65.6%, respectively. The LA values in the atrophic gastritis group were statistically higher than those in the other groups (healthy, chronic gastritis, intestinal metaplasia, and gastric cancer, p<0.0001). The cutoff value to distinguish the atrophic gastritis group from the other four groups was 32.0 U/mL, and its area under the curve was 0.673, which was the highest among the E-plate, pepsinogen (PG) I, PG II, and PG I/II ratio tests in our data. The odds ratios for atrophic gastritis determined by the LA assay and PG I test in multiple logistic regression were 2.5 and 1.9, respectively, which were significantly higher than for the other tests.

Conclusions

: The LA assay can determine the risk of atrophic gastritis, which in turn is a considerable risk factor for gastric cancer. We propose using this assay in combination with the PG I/II ratio to avoid missing gastric cancer patients who have a low LA value (less than 32.0 U/mL).

A comprehensive study of Helicobacter pylori infection: molecular analysis, antibacterial susceptibility, and histopathological examination

Helicobacter pylori is a pathogen associated with gastroduodenal diseases. This study aimed; (i) to investigate H. pylori presence by invasive tests in adult dyspeptic patients, (ii) to determine antibiotic susceptibility and genotypic characteristics of the H. pylori isolates, and (iii) to investigate the relationship between the H. pylori genotypes and the histopathological findings. In this cross-sectional study, gastric biopsy samples from 208 adult dyspeptic patients were used for culture, tissue Polymerase Chain Reaction (PCR), and histopathological analysis. Antibiotic susceptibility of the H. pylori isolates was analyzed by gradient method. Analysis of the virulence genes was performed by monoplex PCR. Genetic profiles (from A to H) were created based on the virulence genes presence. Enterobacterial Repetitive Intergenic Consensus-PCR (ERIC-PCR) was used for the genotyping of the H. pylori isolates. The mean age of the patients was 46 (± 15) years and 128 (61.5%) of them were female. H. pylori positivity was detected by culture, tissue PCR and histopathological examination in 59 (28.4%), 114 (54.8%) and 81 (38.9%) patients, respectively. The overall prevalence of H. pylori was found to be 63% (131/208). All H. pylori isolates were susceptible to tetracycline and amoxicillin. The resistance rates for metronidazole, clarithromycin, levofloxacin, and rifampicin were 67.2%, 27.9%, 34.4% and 13.11%, respectively. Multi drug resistance (MDR) was detected at the rate of 45.9% (28/61). While the most common virulence gene was cagA (93.44%), the least common was vacAm1 (23%). The predominant genetic profile was profile A (47.5%). ERIC-PCR results revealed a total of 26 different patterns. A high prevalence of H. pylori was detected in adult dyspeptic patients as in developing countries. It was observed significant genotypic heterogeneity and virulence gene diversity within the isolates. A considerable resistance rate detected against antibiotics such as clarithromycin, metronidazole, and levofloxacin, which are frequently used in the eradication of H. pylori, should be taken into consideration when creating regional empirical treatment regimens.

Optical detection using CRISPR-Cas12a of Helicobacter pylori for veterinary applications

Helicobacter pylori (H. pylori) is a zoonotic gastric microorganism capable of efficient interspecies transmission. Domesticated companion animals, particularly dogs and cats, serve as natural reservoirs for H. pylori. This phenomenon facilitates the extensive dissemination of H. pylori among households with pets. Hence, the prompt and precise identification of H. pylori in companion animals holds paramount importance for the well-being of both animals and their owners. With the assistance of Multienzyme Isothermal Rapid Amplification (MIRA) and CRISPR-Cas12a system, we successfully crafted a highly adaptable optical detection platform for H. pylori. Three sensor systems with corresponding visual interpretations were proposed. This study demonstrated a rapid turnaround time of approximately 45 min from DNA extraction to the result display. Moreover, this platform topped germiculture and real-time PCR in terms of sensitivity or efficiency in clinical diagnoses of 66 samples. This platform possesses significant potential as a versatile approach and represents the premiere application of CRISPR for the non-invasive detection of H. pylori in companion animals, thereby mitigating the dissemination of H. pylori among household members.

Initial assessment of "Gissell's stain": A novel histopathological method for the identification of Helicobacter pylori

INTRODUCTION AND OBJECTIVES

The histopathological identification of Helicobacter pylori using the routine method (haematoxylin-eosin) is not only very difficult but also has low sensitivity. Giemsa staining is often used in addition, but different protocols do not produce homogeneous results. Furthermore, the Gold Standard recommended by the European Helicobacter Pylori Study Group has been applied in very few studies, thus resulting in uncertain outcomes. Therefore, a new staining method is required to overcome these limitations. The aim of this study was to evaluate the diagnostic capacity and inter-observer agreement of "Gissell's stain".

MATERIAL AND METHODS

A cross-sectional study evaluated 99 gastric paraffin blocks from a private laboratory. Three sections were prepared from each block, and haematoxylin-eosin (HE), Giemsa and "Gissell's stain" methods were applied. The kappa statistics, sensitivity, specificity, and predictive values were calculated.

RESULTS

"Gissell's stain" obtained the highest inter-observer agreement (kappa=0.87) compared to the other two methods (HE, kappa=0.51; Giemsa, kappa=0.83). It also obtained the best sensitivity and negative predictive value (97.1% and 98.3%, respectively) compared with the other two methods (HE: 68.6% and 85.1%, respectively; Giemsa: 88.6% and 93.9%, respectively).

CONCLUSIONS

Given its unique characteristics (fast, cheap, accessible, and easy to use), in addition to its statistical reliability, "Gissell's stain" has great potential for routine use in the identification of H. pylori.

The link between Helicobacter pylori infection and gallbladder and biliary tract diseases: A review

Helicobacter pylori is a gram-negative pathogen commonly associated with peptic ulcer disease and gastric cancer. H. pylori infection has also been reported in cholelithiasis, cholecystitis, gallbladder polyps, and biliary tract cancers. However, the association between H. pylori and gallbladder and biliary tract pathologies remains unclear due to the paucity of literature. In response to the current literature gap, we aim to review and provide an updated summary of the association between H. pylori with gallbladder and biliary tract diseases and its impact on their clinical management. Relevant peer-reviewed studies were retrieved from Medline, PubMed, Embase, and Cochrane databases. We found that H. pylori infection was associated with cholelithiasis, chronic cholecystitis, biliary tract cancer, primary sclerosing cholangitis, and primary biliary cholangitis but not with gallbladder polyps. While causal links have been reported, prospective longitudinal studies are required to conclude the association between H. pylori and gallbladder pathologies. Clinicians should be aware of the implications that H. pylori infection has on the management of these diseases.

Recent progress in biomarker-based diagnostics of Helicobacter pylori, gastric cancer-causing bacteria

The progression of any disease and its outcomes depend on the complicated interaction between pathogens, host and environmental factors. Thus, complete knowledge of bacterial toxins involved in pathogenesis is necessary to develop diagnostic methods and alternative therapies, including vaccines. This review summarizes recently employed biomarkers to diagnose the presence of Helicobacter pylori bacteria. The authors review distinct types of disease-associated biomarkers such as urease, DNA, miRNA, aptamers and bacteriophages that can be utilized as targets to detect Helicobacter pylori and, moreover, gastric cancer in its early stage. A detailed explanation is also given in the context of the recent utilization of these biomarkers in the development of a highly specific and sensitive biosensing platform.

Improving the detection of Helicobacter pylori in biopsies of chronic gastritis: a comparative analysis of H&E, methylene blue, Warthin-Starry, immunohistochemistry, and quantum dots immunohistochemistry

Objectives

The objective of the study was to compare the consistency of various staining methods, including H&E, Methylene Blue, Warthin-Starry (W-S), Immunohistochemistry (IHC) and Quantum dots immunohistochemistry (QDs-IHC), in detecting Helicobacter pylori (HP) in cases of mild, moderate and severe chronic gastritis.

Methods

Biopsy samples were obtained from 225 patients with chronic gastritis at the Department of Pathology, Yichang Central People's Hospital between January 2019 and October 2019. The presence of HP was detected using H&E, Methylene Blue, W-S, IHC, and QDs-IHC.

Results

The positive rates for HP detection using H&E, Methylene Blue, W-S, IHC, and QDs-IHC were 42.22%, 51.11%, 53.78%, 59.11%, and 58.67%, respectively. In cases of mild chronic gastritis, the consistency of test results between H&E, Methylene Blue, W-S, and QDs-IHC with IHC were Kappa=0.196, P=0.033, Kappa=0.706, P<0.001, Kappa=0.717, P<0.001, and Kappa=0.968, P<0.001, respectively. Similarly, in cases of moderate chronic gastritis, Kappa values between H&E, Methylene Blue, W-S, and QDs-IHC with IHC were 0.356, P<0.001, 0.655, P<0.001, 0.741, P<0.001, and 0.946, P<0.001, respectively. For cases of severe chronic gastritis, the Kappa values between the staining methods and IHC were 0.271, P=0.037, 0.421, P=0.002, 0.621, P<0.001, and 1, P< 0.001, respectively.

Conclusion

The study showed that the positivity rate of IHC was significantly higher than that of H&E, Methylene Blue, and W-S in detecting HP infection in chronic gastritis cases. In terms of consistency with IHC, QDs-IHC was the most reliable staining method across all severity grades, while the agreement between H&E and IHC was poor, and that between Methylene Blue and W-S with IHC was average. Pathology departments may choose the most appropriate staining method based on their specific needs, considering the staining time, contrast, and cost of each method.

Possible Role of Helicobacter pylori in Ear Nose and Throat Diseases

Background

Helicobacter pylori is assumed to cause many gastric and extragastric diseases. We aimed to assess the possible association role of H. pylori in Otitis media with effusion (OME), nasal polyps and adenotonsillitis.

Patients and Methods

A total of 186 patients with various ear, nose and throat diseases were included. The study comprised 78 children with chronic adenotonsillitis, 43 children with nasal polyps and 65 children with OME. OME patients were assigned to two subgroups: those who have and those who did not have adenoid hyperplasia. Among the patients with bilateral nasal polyps, 20 individuals had recurrent nasal polyps and 23 had de novo nasal polyps. Patients who have chronic adenotonsillitis were divided into three groups: those with chronic tonsillitis and those who underwent tonsillitis, those with chronic adenoiditis and adenoidectomy was performed, and those with chronic adenotonsillitis and underwent adenotonsillectomy. In addition to examination of H. pylori antigen in stool samples of all included patients, real-time polymerase chain reaction (RT-PCR) for detection of H. pylori in the effusion fluid was performed, additionally, Giemsa stain was used for detection of H. pylori organism within the tissue samples when available.

Results

Frequency of H. pylori in effusion fluid was 28.6% in patients with OME and adenoid hyperplasia, while in those with OME it was only 17.4% with a p value of 0.2. Nasal polyp biopsies were positive in 13% patients of denovo, and 30% patients with recurrent nasal polyps, p=0.2. De novo nasal polyps were more prevalent in the positive stools than recurrent ones, p=0.7. All adenoid samples were negative for H. pylori, only two samples of tonsillar tissue (8.3%) were positive for H. pylori, and stool analysis was positive in 23 patients with chronic adenotonsillitis.

Conclusion

Lack of association between Helicobacter pylori and occurrence of OME, nasal polyposis or recurrent adenotonsillitis.

Moroccan Children With Helicobacter pylori Infection: Demographics, Clinical Features, and Histological Findings

BACKGROUND

Infesting nearly half of the world's population, Helicobacter pylori is thought to cause peptic ulcers and gastric adenocarcinoma. Several studies have examined the association between H. pylori and socioeconomic, clinical, and histological factors in pediatric populations. Similarly, this study aimed to describe the characteristics of H. pylori infection in Moroccan children.

METHODS

Patients aged 1-17 years who underwent upper gastrointestinal endoscopy over a period of two years from January 2019 to January 2021 were included in this study. Gastric biopsies from the antrum and corpus of the stomach were collected. Detection of H. pylori infection was confirmed by Giemsa stain. Demographic data and clinical and endoscopic characteristics were collected and histopathological findings with gastritis scoring were recorded according to the Sydney System.

RESULTS

In 213 children, 95 (45%) were found to be infected with H. pylori, and the infection rates increased as the children aged. While no significant relationship between the infection of H. pylori and all symptoms was founded, a significant association was found in nodular gastritis (p<0.05), and 98% of the infected children had chronic inflammation, which was active in 22% and atrophic in 47%. The atrophy and activity were absent or mild, and the inflammation was mild to moderate.

CONCLUSION

According to this study, nodular gastritis and nonspecific symptoms were related to H. pylori infection in Moroccan children. In addition, the association between this disease and gastric atrophy in our study needs the monitoring of the mucosa of Moroccan children with gastritis and identifying factors that may contribute to gastric cancer.

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

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

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.

Comparison Between Real-time Ammonium and pH Measurement, Immunohistochemistry, and Histochemistry for the Diagnosis of Helicobacter pylori

BACKGROUND

Helicobacter pylori (HP) infection has been implicated in several malignant and nonmalignant conditions. The confirmatory diagnosis of HP requires an endoscopic biopsy, followed by a rapid urease test, culture, and/or histopathologic examination using hemotoxylin and eosin, histochemical stains, or immunohistochemistry against HP. EndoFaster is a novel device that can perform real-time ammonium and pH measurements in gastric juice, allowing a diagnosis of HP during gastroduodenal endoscopy.

GOAL

This study aimed to validate the accuracy of EndoFaster and to compare different histochemical and immunohistochemical techniques for the diagnosis of HP infection.

STUDY

Consecutive patients who underwent upper endoscopy at our center were prospectively enrolled. During the endoscopy procedure, gastric juice was aspirated to perform an automatic analysis by EndoFaster and gastric biopsies were taken. Histologic sections were reviewed to assess the histopathologic features. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated for the EndoFaster test, Diff-Quick (DQ), and immunohistochemistry against HP (anti-HP) using Warthin-Starry as the gold standard for HP detection.

RESULTS

Overall, 80 patients were enrolled. In 19 cases (23,75%), histology was normal. In the remaining cases, varying degrees of inflammation were found. The sensitivity, specificity, positive predictive value, and negative predictive value were 73.33%, 86.00%, 75.86%, and 84.31% for the EndoFaster test using 67 ppm/mL as the positive threshold; 73.33%, 100%, 100%, and 86.21% for DQ; and 79.31%, 88.00%, 79.31%, and 88.00% for anti-HP, respectively.

CONCLUSIONS

The EndoFaster test has good sensitivity and specificity for the diagnosis of HP during the gastroscopy procedure. DQ and anti-HP are excellent alternatives to Warthin-Starry for the detection of HP.

Helicobacter Pylori Infection Is Associated with Neurodegeneration in Cognitively Normal Men

BACKGROUND

An association between Helicobacter pylori (H. pylori) infection and dementia was reported in previous studies; however, the evidence is inconsistent.

OBJECTIVE

In the present study, the association between H. pylori infection and brain cortical thickness as a biomarker of neurodegeneration was investigated.

METHODS

A cross-sectional study of 822 men who underwent a medical health check-up, including an esophagogastroduodenoscopy and 3.0 T magnetic resonance imaging, was performed. H. pylori infection status was assessed based on histology. Multiple linear regression analyses were conducted to evaluate the relationship between H. pylori infection and brain cortical thickness.

RESULTS

Men with H. pylori infection exhibited overall brain cortical thinning (p = 0.022), especially in the parietal (p = 0.008) and occipital lobes (p = 0.050) compared with non-infected men after adjusting for age, educational level, alcohol intake, smoking status, and intracranial volume. 3-dimentional topographical analysis showed that H. pylori infected men had cortical thinning in the bilateral lateral temporal, lateral frontal, and right occipital areas compared with non-infected men with the same adjustments (false discovery rate corrected, Q < 0.050). The association remained significant after further adjusting for inflammatory marker (C-reactive protein) and metabolic factors (obesity, dyslipidemia, fasting glucose, and blood pressure).

CONCLUSION

Our results indicate H. pylori infection is associated with neurodegenerative changes in cognitive normal men. H. pylori infection may play a pathophysiologic role in the neurodegeneration and further studies are needed to validate this association.

Eradication of Helicobacter pylori infection decreases risk for dyslipidemia: A cohort study

BACKGROUND

Previous studies have suggested a relationship between Helicobacter pylori infection and dyslipidemia; however, large-scale longitudinal studies have not elucidated this association. This study assessed the longitudinal effects of H. pylori infection and eradication on lipid profiles in a large cohort.

METHODS

This cohort study included 2,626 adults without dyslipidemia at baseline, who participated in a repeated, regular health-screening examination, which included upper gastrointestinal endoscopy, between January 2009 and December 2018. The primary outcome was incident dyslipidemia at follow-up.

RESULTS

During the 10,324 person-years of follow-up, participants with persistent H. pylori infection had a higher incidence rate (130.5 per 1,000 person-years) of dyslipidemia than those whose infections had been successfully controlled (98.1 per 1,000 person-years). In a multivariable model adjusted for age, sex, waist circumference, smoking status, alcohol intake, and education level, the H. pylori eradication group was associated with a lower risk of dyslipidemia than the persistent group (HR, 0.85; 95% CI, 0.77-0.95; p = 0.004). The association persisted after further adjustment for baseline levels of low-density and high-density lipoprotein cholesterol (HR, 0.87; 95% CI, 0.79-0.97; p = 0.014).

CONCLUSIONS

H. pylori infection may play a pathophysiologic role in the development of dyslipidemia, whereas H. pylori eradication might decrease the risk of dyslipidemia.

Detection of Helicobacter pylori in virtual slides requires high resolution digitalisation

To diagnose Helicobacter pylori (HP) infection and its related mucosal injuries requires the histopathological analysis of gastric biopsies. The move from glass slides interpretation towards digital pathology implies technical choices to maintain the performances of histopathological diagnosis. The intra-rater agreement in assessing gastritis diagnostic criteria between glass slides, low resolution and high resolution digital slides in the subject of the present study. One hundred gastric biopsies were re-assessed by a single digestive pathologist on glass slides and digitalised slides at low resolution (ie, x20 magnification and single focus without z-stack) and high resolution (ie, x40 magnification with seven focus levels and z-stack) about the criteria of the updated Sydney system and the detection of HP. Inter-analyses agreement were very good (Kappa values>0.81) for every criteria but slightly inferior (ie, Kappa values<0.9) comparing glass slides interpretations with low resolution digital slides-based ones. Indeed, some HP infections were misdiagnosed using x20 magnification histochemical stained digitalised slides (p<0.05). At the opposite, anti-HP immunohistochemistry slides and/or x40 magnification digitalisation permitted to maintain almost perfect concordance in diagnosis (Kappa value>0.9). As mentioned in current guidelines, a high resolution x40 magnification digitalisation must be favoured in order to avoid some misdetection of microorganisms as HP.

Helicobacter pylori Antigen But Not the Organism Is Occasionally Present Within Germinal Centers: Implications for Patient Management and Biology

Helicobacter pylori infection is present in two thirds of the world's population and induces a myriad of human diseases, ranging from gastritis to gastric adenocarcinoma and mucosa-associated lymphoid tissue lymphoma. Detection is critical for treatment and may require immunohistochemical (IHC) staining when organisms are not visible on hematoxylin and eosin. We have encountered cases in which IHC for Helicobacter pylori failed to demonstrate curvilinear or coccoid organisms, but did show a reticular pattern of immunoreactivity involving the underlying germinal centers. We performed a systematic retrospective evaluation of the frequency of H. pylori germinal center immunoreactivity over a 54-month period through evaluation of 367 gastric specimens. H. pylori germinal center immunoreactivity was observed in 5% of cases with germinal centers. Nine of 11 (81%) patients with H. pylori germinal center immunoreactivity had concurrent or recent H. pylori infection, in comparison to 36% of patients with germinal centers present but no immunoreactivity (n=9 of 25 patients, P=0.03). None of the patients with germinal center immunoreactivity developed mucosa-associated lymphoid tissue lymphoma. In situ hybridization for H. pylori performed on 3 cases with positive germinal center IHC was negative for H. pylori nucleic acids within those germinal centers, demonstrating that only the antigen is present. This work demonstrates that H. pylori antigen, but not viable organisms, is present in germinal centers in 5% of gastric specimens, and is associated with recent or concurrent H. pylori infection. We advocate for reporting of all H. pylori germinal center immunoreactivity with a recommendation for ancillary H. pylori testing.

Evaluation of Better Staining Method among Hematoxylin and Eosin, Giemsa and Periodic Acid Schiff-Alcian Blue for the Detection of Helicobacter pylori in Gastric Biopsies

Background

This study was undertaken to evaluate the preferred method (Giemsa or periodic acid Schiff-Alcian blue [PAS-AB] stains) of detecting Helicobacter pylori (H. pylori) in gastric mucosal biopsies in terms of sensitivity, specificity and applicability. To the best of my knowledge, this is the first report comparing Giemsa and PAS-AB staining for the detection of H. pylori in such biopsies.

Methods

The formalin-fixed paraffin-embedded blocks of 49 gastric biopsies from different patients were collected from the archive of anatomical pathology at King Abdulaziz Medical City, National Guard, Riyadh, Saudi Arabia. From each block, three slides were prepared and analysed using the hematoxylin and eosin (H&E), Giemsa and PAS-AB stains to detect the presence/absence of H. pylori, and the results were compared in terms of sensitivity, specificity and applicability.

Results

The majority of the biopsies in this study showed antrum-type gastric mucosa. Only 15 biopsies showed active gastritis, whereas the rest showed chronic gastritis. Three biopsies showed intestinal metaplasia. All were detected by PAS-AB stain, but only two-thirds were detected by H&E stain. Fifteen gastric biopsies showed H. pylori infection in general and in 13 of them, active gastritis cases were discovered. Fourteen out of these 15 H. pylori infection cases were detected by Giemsa stain, whereas only 13 cases were detected by H&E stain. PAS-AB stain showed the worst results since it demonstrated only 40% sensitivity and 67.65% specificity in H. pylori detection.

Conclusion

Giemsa stain has better sensitivity and specificity in gastric H. pylori infection detection than PAS-AB. Therefore, using PAS-AB stain to detect H. pylori infection is not recommended.

Heterogeneity Measurement of Cardiac Tissues Leveraging Uncertainty Information from Image Segmentation

Identifying arrhythmia substrates and quantifying their heterogeneity has great potential to provide critical guidance for radio frequency ablation. However, quantitative analysis of heterogeneity on cardiac optical coherence tomography (OCT) images is lacking. In this paper, we conduct the first study on quantifying cardiac tissue heterogeneity from human OCT images. Our proposed method applies a dropout-based Monte Carlo sampling technique to measure the model uncertainty. The heterogeneity information is extracted by decoupling the intra/inter-tissue heterogeneity and tissue boundary uncertainty from the uncertainty measurement. We empirically demonstrate that our model can highlight the subtle features from OCT images, and the heterogeneity information extracted is positively correlated with the tissue heterogeneity information from corresponding histology images.

Helicobacter pylori: Perturbation and restoration of gut microbiome

Alternate remedies with natural products provides unlimited opportunities for new drug development. These can be either as pure compounds or as standardized set of compounds. The phytochemicals and secondary metabolites are in great demand for screening bioactive compounds and plays an important role towards drug development. Natural products have many advantages over to synthetic chemical drugs. Helicobacter pylori (H. pylori) a Gram-negative bacteria has been classified as Class I carcinogen by World Health Organization in 1994. Current treatment regimens for H. pylori is ‘triple therapy’ administrated for two weeks which includes a combination of two antibiotics like Amoxicillin and Clarithromycin and a proton pump inhibitor (PPI) like Lansoprazole, and for ‘quadruple therapy’ in addition to antibiotics and a PPI, Bismuth is used. Antibiotic resistance can be named as the main factor for failure of treatment of H. pylori infection. The need of the hour is to develop a herbal remedy that could combat the growth of H. pylori. Probiotics can also be used as ‘feasible’ tool for H. pylori infection management. Present review is an attempt to briefly discuss about the pathogenicity, genetic predisposition, perturbation of gut microbiota due to antibiotic treatment and restoration of healthy gut microbiota with phytochemicals and probiotics.

Helicobacter pylori Infection and the Development of Advanced Colorectal Neoplasia

BACKGROUND

An association between Helicobacter pylori infection and colorectal neoplasia has been reported in cross-sectional studies.

GOALS

We examined the association between H. pylori infection and the development of advanced colorectal neoplasia (AN) in a screening cohort.

STUDY

We identified 3753 adults, who underwent screening and subsequent surveillance colonoscopies. The primary outcome was the development of metachronous AN, as confirmed by surveillance colonoscopy. H. pylori infection status was assessed by an H. pylori-specific immunoglobulin G antibody test. Sensitivity analysis was also performed by H. pylori infection status on the basis of histology.

RESULTS

During a median follow-up of 41 months, the incidence of AN was 3.2% and 1.7% in participants with and without H. pylori infection, respectively. In multivariable analysis adjusted for age, body mass index, smoking status, alcohol intake, family history of colorectal cancer, and baseline adenoma characteristics, the hazard ratio [95% confidence interval (CI)] for metachronous AN was 1.74 (1.11-2.73) in participants with H. pylori seropositivity, compared with those without H. pylori seropositivity. The association was consistent with H. pylori infection status on the basis of histology (adjusted hazard ratio, 3.51; 95% CI, 1.64-7.51). In the subgroup analysis, the positive association was observed in both no-adenoma and adenoma removal subgroups.

CONCLUSIONS

In a cohort study, H. pylori infection was associated with an increased risk of AN development. This association was consistent in both the serological and histologic assessment of H. pylori infection. Prospective studies are necessary to determine whether H. pylori eradication can reduce the risk of colorectal neoplasia.

Triple-nanostructuring-based noninvasive electro-immune sensing of CagA toxin for Helicobacter pylori detection

BACKGROUND

Helicobacter pylori (H pylori) is gram-negative, spiral, and microaerophilic bacteria which can survive in ~2%-10% oxygen level. It was reported to populate in human gastric mucosa and leads to gastric cancer without any age or gender difference.

MATERIALS AND METHODS

In this study, we are targeting label-free electrochemical immunosensor development for rapid H pylori detection after covalently immobilizing the antibody (CagA) over the nanomaterials modified Au electrode. Titanium oxide nanoparticles (TiO₂ NPs), carboxylated multi-walled carbon nanotubes (c-MWCNT), and conducting polymer polyindole carboxylic acid (Pin5COOH) composites (TiO₂ NPs/c-MWCNT/Pin5COOH) were synthesized and further utilized in immunosensor development as an electrochemical interface onto Au electrode. The stepwise modifications of CagAantibody/TiO₂ NPs/c-MWNCT/Pin5COOH/Au electrode were electrochemically studied.

RESULTS

Possessing the unique features of advanced materials, the proposed immunosensor reported low sensing limit of 0.1 ng/mL in dynamic linear range of 0.1-8.0 ng/mL with higher stability and reproducibility. Furthermore, developed sensor-based determination of H pylori in five human stool specimens has shown good results with suitable accuracy.

CONCLUSIONS

This work lays strong foundation toward developing nanotechnology-enabled electrochemical sensor for ultrasensitive and early detection of H pylori in noninvasively collected clinical samples.

DETECTION OF HELICOBACTER PYLORI INFECTION IN CHRONIC GASTRITIS BIOPSY SPECIMEN USING WARTHIN-STARRY AND MODIFIED GIEMSA STAIN IN DR SOETOMO HOSPITAL SURABAYA

Helicobacter pylori is a bacteria that commonly cause chronic gastritis. Identification of its infection is essential for eradication treatment. Detection of H.pylori bacteria in gastric biopsy specimen by histology method is a diagnostic tool that widely accepted because it is superior to serology examination. Although the bacteria can be seen in routinely Hematoxylin-Eosin staining, Modified Giemsa and Whartin Starry stain was commonly used to see the bacteria more clearly. Whartin Starry stain gives more contrast to the bacteria but modified Giemsa stain is preferable at many centres because it is a cheaper and simpler method. This study want to find out whether there is difference result in detection of H.pylori using these two stains. Material and methods. Paraffin blocks from gastric biopsy patients with chronic gastritis were retrieved from Anatomic Pathology Laboratory Dr.Soetomo Hospital Surabaya in the year 2017. Thirty paraffin blocks were taken randomly and were made into microscopic slides for staining with Warthin-starry and modified Giemsa stain concomitantly. Results. Specimen with Whartin starry stain show 19 out of 30 were positive for H.pylori while modified-Giemsa stain found 16 out of 30 specimen were positive for H.pylori. Whartin Starry stain use silver reagent to coat the bacteria so it become more clearly visible. Conclusion. Detection of H.pylori Warthin-starry stain give more chance to obtain positive result because it use silver technique that coat the bacteria making it is more clearly visible in microscopic examination.   

Application of PCR and Microscopy to Detect Helicobacter pylori in Gastric Biopsy Specimen among Acid Peptic Disorders at Tertiary Care Centre in Eastern Nepal

BACKGROUND

Helicobacter pylori infection is most prevalent in developing countries. It is an etiological agent of peptic ulcer, gastric adenocarcinoma, and mucosal-associated lymphoid tissue (MALT) lymphoma. Despite the development of different assays to confirm H. pylori infection, the diagnosis of infection is challenged by precision of the applied assay. Hence, the aim of this study was to understand the diagnostic accuracy of PCR and microscopy to detect the H. pylori in the gastric antrum biopsy specimen from gastric disorder patients.

METHODS

A total of 52 patients with gastric disorders underwent upper gastrointestinal endoscopy with biopsy. The H. pylori infection in gastric biopsies was identified after examination by microscopy and 23S rRNA specific PCR. The agreement between two test results were analysed by McNemar's test and Kappa coefficient.

RESULT

H. pylori infection was confirmed in 9 (17.30%) patients by both assays, 6.25% in antral gastritis, 22.22% in gastric ulcer, 100% in gastric ulcer with duodenitis, 50% in gastric ulcer with duodenal ulcer, and 33.33% in severe erosive duodenitis with antral gastritis. Out of nine H. pylori infection confirmed patients, 3 patients were confirmed by microscopy and 8 patients by PCR. In case of two patients, both microscopy and PCR assay confirmed the H. pylori infection. The agreement between two test results was 86.54% and disagreed by 13.46% (p value > 0.05).

CONCLUSION

We found that PCR assay to detect H. pylori is more sensitive than microscopy. However, we advocate for the combination of both assays to increase the strength of diagnostic accuracy due to the absence of the gold standard assay for H. pylori infection.

Helicobacter pylori may be an initiating factor in newly diagnosed ulcerative colitis patients: A pilot study

AIM

To directly visualize Helicobacter pylori (H. pylori) by the highly sensitive and specific technique of immunohistochemical staining in colonic tissue from patients newly diagnosed with ulcerative colitis (UC).

METHODS

Colonoscopic biopsies from thirty patients with newly diagnosed UC and thirty controls were stained with Giemsa stain and immunohistochemical stain for detection of H. pylori in the colonic tissue. Results were confirmed by testing H. pylori Ag in the stool then infected patients were randomized to receive either anti H. pylori treatment or placebo.

RESULTS

Twelve/30 (40%) of the UC patients were positive for H. pylori by Giemsa, and 17/30 (56.6%) by immunohistochemistry stain. Among the control group 4/30 (13.3%) and 6/30 (20 %) were positive for H. pylori by Giemsa and immunohistochemistry staining respectively. H. pylori was significantly higher in UC than in controls (P = 0.04 and 0.007). All Giemsa positive patients and controls were positive by immunohistochemical stain. Four cases of the control group positive for H. pylori also showed microscopic features consistent with early UC.

CONCLUSION

H. pylori can be detected in colonic mucosa of patients with UC and patients with histological superficial ulcerations and mild infiltration consistent with early UC. There seems to be an association between UC and presence of H. pylori in the colonic tissue. Whether this is a causal relationship or not remains to be discovered.

Histochemistry in the diagnosis of non-neoplastic gastrointestinal disorders

The alimentary tract serves as host to a large number of diseases. In the non-neoplastic group of disorders, conventional histochemistry continues to play an important diagnostic role. It is particularly important in recognizing specific infectious diseases, such as Helicobacter gastritis, Whipple disease, intestinal tuberculosis and other forms of mycobacteriosis, malakoplakia, intestinal spirochetosis, fungal enteritides, amebiasis, cryptosporidiosis, isosporiasis, and microsporidiosis. Those conditions and their histochemical properties are discussed in this review, along with the use of histochemistry in the characterization of structural gastrointestinal disorders. The latter include mucosal metaplasias, amyloidosis, glycogenic acanthosis of the esophagus, lymphocytic-collagenous colitis, gastric neuroendocrine hyperplasia, and pill gastritis.

Warthin-Starry Staining for the Detection of Helicobacter pylori in Gastric Biopsies

Background

Warthin-Starry (WS) staining is an ancillary stain used in the detection of Helicobacter sp., spirochaete and other microorganisms in tissue sections. The present study aimed to determine the validity of WS stain in the confirmation of H. pylori diagnosis in gastric biopsies in comparison with anti-H. pylori immunohistochemistry (IHC) staining.

Methods

This study involved 104 cases of gastric biopsies that were previously subjected to WS staining. All cases involved retrieval of formalin-fixed paraffin-embedded (FFPE) gastric biopsies that were re-cut, subjected to anti-H. pylori IHC staining and reviewed blindly by a pathologist. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of WS as compared to IHC were calculated.

Results

In this study, WS stain was less sensitive in detecting H. pylori. The sensitivity, specificity, PPV and NPV for WS stain were 50.0%, 92.4%, 79.2% and 76.3%, respectively.

Conclusions

The sensitivity of WS stain in the histopathology laboratory was lower than that described previously. Several external factors that might influence the results were identified. However, sufficient information on patients’ history of treatment and medication would be required for the diagnosis or confirmation of the presence of H. pylori in gastric biopsies by WS staining.

[Study of the evolution in the activity of a Department of Pathology from a third level hospital in the last decade (2007-2016)]

OBJECTIVE

To study the evolution of variables of interest in a department of pathology from a third level hospital during the last decade and to evaluate the impact on these of the hospital relocation in 2014.

MATERIAL AND METHOD

Retrospective observational study in which the recorded samples (biopsies, cytology specimens, FNA, autopsies, intraoperative) as well as the complementary techniques (IHC, Histochemistry, IF and FISH) and portfolio of services were analyzed during the years 2007-2016 inclusive. For the statistical analysis, the five-year periods 2007-2011 and 2012-2016 were compared.

RESULTS

The following variables were statistically significant: cytology (34055.8±1994.0 vs 26590.4±2938.3, p=0.002), autopsies (156.2±27.3 vs 122.0±14.78, p=0.039), immunohistochemistry (17855.4±3424.2 vs 28559.2±4734.7, p=0.003), histochemistry (11117.8±2300.9 vs 6225.0±1330.5, p=0.003) and immunofluorescence (610.2±185.3 vs. 1205.4±154.0, p=0.001). Statistical correlations of interest among variables have been identified. In 2014, it was observed that the variables of greater specific weight (biopsies, cytology, IHQ and histochemistry) in the work load of the Department showed an average decrease of 12.5%. A generalized increase in the panel of available samples has been identified, the largest increase being seen in the number of antibodies (78.7%), histochemistry (38.7%) and FISH (400%).

CONCLUSION

Relevant variations in work volume, as well as the service portfolio, have been identified, especially in the techniques aimed at improving diagnostic accuracy (IHQ and FI), and a significant decrease in the number of cytology specimens, autopsies and histochemistry. In the year 2014 a decrease of more than 12% in the main variables of the study was observed.

Diagnosis of Helicobacter pylori Using Invasive and Noninvasive Approaches

Helicobacter pylori (H. pylori) as gram-negative and spiral microorganism is responsible for colonization in the gastric microniche for more than 50% of world population. Recent studies have shown a critical role of H. pylori in the development of peptic ulcers, gastric mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric cancer. Over the past decade, there has been a sharp interest to use noninvasive tests in diagnosis of the H. pylori infection. During the years after discovery by Marshall and Warren, it has been frequently declared that the rapid urease test (RUT) is one of the cheapest and rapid diagnostic approaches used in detecting the infection. Although the specificity and sensitivity are durable for this test, clinical experiences had shown that the ideal results are only achieved only if we take biopsies from both corpus and antrum at the same time. Given the diagnosis of the H. pylori in clinical samples, gastroenterologists are facing a long list of various molecular and nonmolecular tests. We need more in-depth researches and investigations to correctly generalize rapid and accurate molecular tests determining both bacterial identity and antibiotic resistance profile.

GenoType® HelicoDR test in comparison with histology and culture for Helicobacter pylori detection and identification of resistance mutations to clarithromycin and fluoroquinolones

BACKGROUND

There are several methods for Helicobacter pylori infection diagnosis.

AIM

The efficacies of three methods for H. pylori identification directly from a biopsy were compared: histology, culture, and molecular GenoType® HelicoDR test.

MATERIALS & METHODS

Eighty-five triplicates of stomach antrum biopsies were obtained during gastroscopy procedures for culture, histology, and molecular assay. In addition, we performed molecular identification of genes encoding resistance to clarithromycin and fluoroquinolones.

RESULTS

The results have shown that the most specific method with the highest number of positive specimens was by molecular kit, compared to culture and histology (94.3%, 77.1%, and 71.4%, respectively). There was a higher rate of resistance mutations to clarithromycin than to fluoroquinolones (68.26% vs 20%). The most common mutations for clarithromycin and fluoroquinolones resistance were found in alleles A2143G and N87K, respectively. The highest rate of positive specimens was identified by the molecular.

DISCUSSION

GenoType HelicoDR kit (94.3%), which has several advantages: direct identification, strain resistance characterization, mixture of genotypes detection, and no transport or storage limitations; thus, it is an excellent epidemiological screening tool. This work has demonstrated a lower resistance rate to fluoroquinolones; it is possible that in the investigated geographic area treatment with fluoroquinolones may be preferable to clarithromycin. GenoType® HelicoDR test eliminates the need for culture performance and susceptibility tests for several common antibiotic agents and enables optimal and specific antibiotic treatment adjustment.

CONCLUSION

We recommend a combination of PCR assay and bacterial culture for a quick method of screening and more efficient identification of H. pylori strains and resistance patterns.

Upfront immunohistochemistry improves specificity of Helicobacter pylori diagnosis. A French pathology laboratory point of view

BACKGROUND

There is no consensus about the histopathologic methods to detect Helicobacter pylori in gastric biopsies to date. We aimed to question about the value of upfront anti-H. pylori immunohistochemistry in this field.

MATERIAL AND METHODS

We led a retrospective study about the rate of H. pylori-positive gastric biopsies before and after the implementation of upfront immunohistochemistry, the inter-rater and intermethods agreements in H. pylori identification about Hematoxylin-Eosin Saffron (HES), Giemsa, and immunohistochemistry stains and the histopathologic features associated with low amounts of H. pylori.

RESULTS

First, the rate of H. pylori-positive gastric biopsies significantly diminished after the implementation of upfront immunohistochemistry (from 21.15% to 12.56%, P<.0001), suggesting potential overdiagnosis of H. pylori infection before the use of immunohistochemistry. Secondly, immunohistochemistry was the most reproducible and performing stain (kappa values >0.80), but HES and Giemsa stains also presented good-to-very good agreements. Finally, less than 1% of gastric biopsies with inconspicuous H. pylori infection showed no mucosal injury pointing out that any HES-detected mucosal injury could help to preselect the gastric biopsies requiring ancillary stains for the detection of H. pylori.

CONCLUSIONS

Albeit being considered as a gold standard in the detection of H. pylori, the interest of using immunohistochemistry as an upfront stain on gastric biopsies is still debated. In our opinion, its use in second line in case of ambiguous HE/HES-Giemsa result is more appropriate. Further effort is needed to optimize the inexpensive but feasible HE/HES-based detection of H. pylori.

Sensitivity of Helicobacter pylori detection by Giemsa staining is poor in comparison with immunohistochemistry and fluorescent in situ hybridization and strongly depends on inflammatory activity

BACKGROUND

Conventional stainings (including H&E and special stains like Giemsa) are the most widely applied histopathologic detection methods of Helicobacter pylori (HP).

MATERIALS AND METHODS

We aimed to compare the diagnostic performance of Giemsa staining with immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) on a monocentric cohort of 2896 gastric biopsies and relate results to histologic alterations in order to find such histopathologic subgroups in which these methods underperform. All cases were categorized regarding presence or absence of chronic gastritis, inflammatory activity, and mucosal structural alterations.

RESULTS

Giemsa revealed 687 cases (23.7%), IHC 795 cases (27.5%), and FISH 788 cases (27.2%) as being HP positive. Giemsa showed significantly lower overall sensitivity (83.3%) compared to IHC (98.8%) and FISH (98.0%). Moreover, the sensitivity of Giemsa dramatically dropped to 33.6% in the nonactive cases. We found that sensitivity of Giemsa strongly depends on HP density and, accordingly, on the presence of activity. Structural alterations (intestinal metaplasia, atrophy, etc.) had only no or weak effect on sensitivity of the three stainings. Both IHC and FISH proved to be equally reliable HP detecting techniques whose diagnostic performance is minimally influenced by mucosal inflammatory and structural alterations contrary to conventional stainings.

CONCLUSIONS

We highly recommend immunohistochemistry for clinically susceptible, nonactive chronic gastritis cases, if the conventional stain-based HP detection is negative. Moreover, we recommend to use IHC more widely as basic HP stain. Helicobacter pylori FISH technique is primarily recommended to determine bacterial clarithromycin resistance. Furthermore, it is another accurate diagnostic tool for HP.

Oxidative Phosphorylation System in Gastric Carcinomas and Gastritis

Switching of cellular energy production from oxidative phosphorylation (OXPHOS) by mitochondria to aerobic glycolysis occurs in many types of tumors. However, the significance of this switching for the development of gastric carcinoma and what connection it may have to Helicobacter pylori infection of the gut, a primary cause of gastric cancer, are poorly understood. Therefore, we investigated the expression of OXPHOS complexes in two types of human gastric carcinomas ("intestinal" and "diffuse"), bacterial gastritis with and without metaplasia, and chemically induced gastritis by using immunohistochemistry. Furthermore, we analyzed the effect of HP infection on several key mitochondrial proteins. Complex I expression was significantly reduced in intestinal type (but not diffuse) gastric carcinomas compared to adjacent control tissue, and the reduction was independent of HP infection. Significantly, higher complex I and complex II expression was present in large tumors. Furthermore, higher complex II and complex III protein levels were also obvious in grade 3 versus grade 2. No differences of OXPHOS complexes and markers of mitochondrial biogenesis were found between bacterially caused and chemically induced gastritis. Thus, intestinal gastric carcinomas, but not precancerous stages, are frequently characterized by loss of complex I, and this pathophysiology occurs independently of HP infection.

Diagnosis of Helicobacter pylori infection: Current options and developments

Accurate diagnosis of Helicobacter pylori (H. pylori) infection is a crucial part in the effective management of many gastroduodenal diseases. Several invasive and non-invasive diagnostic tests are available for the detection of H. pylori and each test has its usefulness and limitations in different clinical situations. Although none can be considered as a single gold standard in clinical practice, several techniques have been developed to give the more reliable results. Invasive tests are performed via endoscopic biopsy specimens and these tests include histology, culture, rapid urease test as well as molecular methods. Developments of endoscopic equipment also contribute to the real-time diagnosis of H. pylori during endoscopy. Urea breathing test and stool antigen test are most widely used non-invasive tests, whereas serology is useful in screening and epidemiological studies. Molecular methods have been used in variable specimens other than gastric mucosa. More than detection of H. pylori infection, several tests are introduced into the evaluation of virulence factors and antibiotic sensitivity of H. pylori, as well as screening precancerous lesions and gastric cancer. The aim of this article is to review the current options and novel developments of diagnostic tests and their applications in different clinical conditions or for specific purposes.

Helicobacter pylori in Cholecystectomy Specimens-Morphological and Immunohistochemical Assessment

INTRODUCTION

Helicobacter pylori (H.pylori) is associated with gastritis, peptic ulcer, gastric carcinoma and gastric lymphoma. Current literature describes presence of H.pylori in various extra-gastric locations and its association with many diseases. Apart from the conventional location of gastric and duodenal mucosa, H.pylori have been isolated and cultured from gallbladder.

AIM

Analysis of cholecystectomy specimens to detect H.pylori by means of immunohistochemical staining.

MATERIALS AND METHODS

There were a total of 118 cholecystectomy specimens received in the Department of Pathology in three months duration. We have performed immunostaining for H.pylori in 45 consecutive cases of cholecystectomy specimen. Clinical and other investigational information were retrieved from the medical records department. For each case, routine Haematoxylin and Eosin stain was studied. Immunohistochemistry (IHC) was done using purified polyclonal Helicobacter pylori antiserum.

RESULTS

Majority of the patients had undergone laparoscopic cholecystectomy for the presenting complaint of right hypochondrial pain. Multiple pigmented stones were present in majority (27/45) of them. Immunostain for H.pylori was positive in ten cases. Six of these cases had pigmented gall stones, two had stones not specified and in two of the cases there were no stones.

CONCLUSION

Helicobacter pylori is present in gall bladder and is commonly seen in association with stones. A more detailed study of cholecystectomy cases (both neoplastic and non-neoplastic) with serological, culture and molecular data of H.pylori is desirable to study the pathogenesis of cholecystitis, its association with gall stones and other gall bladder disorders.

Braf, Kras and Helicobacter pylori epigenetic changes-associated chronic gastritis in Egyptian patients with and without gastric cancer

We aimed to study MLH1 and MGMT methylation status in Helicobacter pylori-associated chronic gastritis in Egyptian patients with and without gastric cancer. 39 patients were included in our study. They were divided into 2 groups; patients without (group I) and with gastric adenocarcinoma (group II). Patients were subjected to clinical examination, abdominal ultrasound and upper endoscopy for gastric biopsy. Biopsies were subjected to urease test, histological examination, and DNA purification. H. pylori, Braf, Kras, MLH1 and MGMT methylation were assessed by quantitative PCR. DNA sequencing was performed to assess Braf and Kras genes mutation. qPCR of H. pylori was significantly higher in patients with adenocarcinoma (group II) than those without adenocarcinoma (group I); with a p < 0.001 as well as in patients with age above 50 years with a p value = 0.008. By applying logistic regression analysis it was reported that the H. pylori qPCR is a significant predictor to the adenocarcinoma with OR = 1.025 (95 % CI: 1. 002-1.048), with sensitivity of 90 % and specificity of 100 %. Adenocarcinoma patients had a significantly higher mean age and levels of H. Pylori, Braf, K-ras, methylated MGMT and methylated MLH1 than those of gastritis patients. DNA sequence analysis of Braf (codon 12) and Kras (codon 600) had genes mutation in gastric adenocarcinoma versus chronic gastritis.

CONCLUSION

H. pylori may cause epigenetic changes predisposing the patients to cancer stomach. Estimation of H. pylori by qPCR can be a good predictor to adenocarcinoma. Braf and Kras genes mutation were reveled in gastritis and adenocarcinoma patients.

Helicobacter pylori chronic gastritis updated Sydney grading in relation to endoscopic findings and H. pylori IgG antibody: diagnostic methods

Helicobacter pylori (Hp) inhabits the stomach of > 50% of humans and has been established as a major etiological factor in the pathogenesis of chronic gastritis, gastric atrophy, peptic ulcer disease, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. The aim of this study was to provide unequivocal information about Hp-associated gastritis grading according to the Sydney grading system and to compare the histopathological features with the endoscopic findings and anti-Hp immunoglobulin (Ig)G serological status. This analytical study was conducted on 157 patients with dyspeptic gastritis. All patients underwent esophagogastroduodenoscopy, and antrum and corpus biopsies were taken. Blood samples were obtained from all participants. Different stains were performed on formalin-fixed, paraffin-embedded tissue blocks that included hematoxylin and eosin and Giemsa stain for histopathological interpretation. The endoscopic findings of gastritis were observed in 120 patients and most of them showed hyperemia (80 patients), whereas seven patients had normal appearing gastric mucosa. Histologically variable numbers of mononuclear inflammatory cellular infiltrates were seen in 150 cases (95.5%). Most of them showed Grade 1 gastritis (80 patients), whereas Grades 2 and 3 were found in 43 and 27 biopsies, respectively. Hp colonization was observed in most of the examined biopsies (93.7%). Hp-IgG seropositivity was found in 80.9% of cases and 19.1% were seronegative. The relationship between endoscopic and histological findings was significant (p < 0.001).

The diagnostic accuracy of rapid urease biopsy test compared to histopathology in implementing "test and treat" policy for Helicobacter pylori

Background:

Helicobacter pylori is one of the most important causes of the varied spectrum of gastroduodenal diseases. It is important to have a rapid diagnostic method to detect the organism so as to initiate the treatment early and check its progression to malignancy.

Aims:

To evaluate the diagnostic accuracy of rapid urease biopsy test in detecting H. pylori infection and implementation of “test and treat” policy.

Materials and Methods:

All patients of chronic dyspepsia not responding to conventional treatment were subjected to endoscopy, and mucosal biopsy samples were collected. A rapid urease test (RUT) and histopathology was performed on these samples and taking histopathology as gold standard for H. pylori demonstration, the diagnostic accuracy of RUT was evaluated.

Results:

The specificity, sensitivity, positive predictive value, negative predictive value, and diagnostic accuracy of RUT were 97.22%, 94.04%, 98.75%, 87.5%, and 95%, respectively.

Conclusion:

Use of a rapid diagnostic test viz., rapid urease biopsy test to confirm H. pylori infection is recommended for early diagnosis and treatment of H. pylori associated gastroduodenal diseases.

Detection of Helicobacter pylori in Nasal Polyps

To detect the presence of Helicobacter pylori in nasal polyps. A case-control study was conducted enrolling 35 patients with nasal polyps (cases) and patients undergoing septoplasty (controls). Fresh tissue samples were used for urea broth test and imprint cytology, while formalin fixed tissue sections were used for morphology, special stains and immunohistochemistry for H. pylori. Fresh stool samples from both groups were tested to correlate the gastrointestinal status. H. pylori was detected in 40.0 % (14/35) of cases and 8.5 % of controls (3/35) (p = 0.004) by immunohistochemistry. Amongst cases, eight were positive with urea broth test, six with imprint cytology (Giemsa stain), three with H & E, and nine with modified McMullen's stain. Hyperplasia of the lining epithelium and lymphoid aggregates were significantly noticed in nasal polyps positive for H. pylori. Stool antigen test was positive in subjects who were positive for H. pylori in the nasal mucosa. There appears to be an association between H. pylori and nasal polyps. Immunohistochemistry is more sensitive and specific method to detect H. pylori. H. pylori induced inflammatory tissue reaction pattern indicates a possible causal association. Further studies are needed to prove the causal relationship between H. pylori and nasal polyps.

Antisecretory medication is associated with decreased Helicobacter pylori detection in gastric marginal zone lymphoma

Helicobacter pylori status influences the prognosis and management of gastric extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), so accurate determination of H pylori status is of clinical importance. The low rate of histologic H pylori positivity among gastric MALT lymphoma cases at our institution prompted investigation for possible causes. A case series of 24 patients as having gastric MALT lymphoma (with no diffuse large B-cell component) in a tertiary care setting between 1997 and 2010 was identified, and clinical records were reviewed. Immunohistochemical staining for H pylori and BCL10 was performed. This study received institutional review board approval (protocol number M13-033). Thirty-nine percent of cases (9/23) were H pylori positive by histology, and 4 additional patients had positive serologic results; overall, 57% of cases (13/23) were positive for H pylori. Treatment with antisecretory medications was associated with a lower likelihood of histologic positivity (13% among treated patients vs 75% among untreated; P = .04). Nuclear localization of BCL10 was seen in 2 cases and was not associated with H pylori status. Antisecretory medications decrease the likelihood of histologic detection of H pylori in gastric MALT lymphoma cases. Incorporation of results of serologic or other testing is needed to ensure correct classification with respect to H pylori status.

Diagnosis of Helicobacter pylori Infection in the Proton Pump Inhibitor Era

Proton pump inhibitors (PPI) are a major cause of false-negative Helicobacter pylori test results. Detecting PPI use and stopping it 2 weeks before testing is the preferred approach to improve the reliability of H pylori diagnostic tests. Immunoblot and molecular methods may be useful for the detection of H pylori infection in difficult cases. When conventional tests are negative and eradication is strongly indicated, empirical H pylori treatment should be considered. In this article, an updated critical review of the usefulness of the various invasive and noninvasive tests in the context of extensive PPI use is provided.

Histological Stains: A Literature Review and Case Study

The history of histology indicates that there have been significant changes in the techniques used for histological staining through chemical, molecular biology assays and immunological techniques, collectively referred to as histochemistry. Early histologists used the readily available chemicals to prepare tissues for microscopic studies; these laboratory chemicals were potassium dichromate, alcohol and the mercuric chloride to harden cellular tissues. Staining techniques used were carmine, silver nitrate, Giemsa, Trichrome Stains, Gram Stain and Hematoxylin among others. The purpose of this research was to assess past and current literature reviews, as well as case studies, with the aim of informing ways in which histological stains have been improved in the modern age. Results from the literature review has indicated that there has been an improvement in histopathology and histotechnology in stains used. There has been a rising need for efficient, accurate and less complex staining procedures. Many stain procedures are still in use today, and many others have been replaced with new immunostaining, molecular, non-culture and other advanced staining techniques. Some staining methods have been abandoned because the chemicals required have been medically proven to be toxic. The case studies indicated that in modern histology a combination of different stain techniques are used to enhance the effectiveness of the staining process. Currently, improved histological stains, have been modified and combined with other stains to improve their effectiveness.

Prevalence of Helicobacter pylori in dyspeptic patients at a tertiary hospital in a low resource setting

Background

More than half of the world’s population is infected with Helicobacter pylori (H. pylori), the primary cause of chronic gastritis. Chronic gastritis is associated with peptic ulcer and in advanced stages with an increased risk of developing gastric adenocarcinoma. In many developing countries access to upper gastrointestinal (UGI) endoscopy services is limited. As a result, many UGI diseases are treated empirically.

Objective

To determine the prevalence of H. pylori in patients presenting with dyspepsia, and the mean time from onset of symptoms to performing an endoscopy examination.

Methods

A cross sectional descriptive study conducted from 5th January to 30th April 2014. Adult patients with dyspepsia who were referred for UGI endoscopy were recruited consecutively. Questionnaires were used to collect data which were analyzed using STATA software. IRB approval was obtained.

Results

In total, 111 participants’ data were analyzed. The F:M ratio was 1:1.4, mean age 43 years (SD = 16). The prevalence of H. pylori gastritis was 36%. The minimum time to endoscopy was 3 weeks, maximum 1,248 weeks and the mean time 57 weeks.

Conclusion

The burden of H. pylori infection in patients with dyspepsia was high. Patients had prior empirical antibiotic therapy. Access to endoscopic services is limited.

Epinecidin-1 antimicrobial activity: In vitro membrane lysis and In vivo efficacy against Helicobacter pylori infection in a mouse model. Biomaterials. 2015;61:41-51. [PMID: 25996410 DOI: 10.1016/j.biomaterials.2015.05.014]

Helicobacter pylori (H. pylori) infection is highly prevalent, and has a strong association with various gastric diseases, including gastritis, digestive ulcers, and cancer. H. pylori strains with resistance to existing antibiotics have emerged in the past two decades. Currently, treatment of H. pylori infection (involving the use of proton pump inhibitors, followed by triple therapy with broad-spectrum antibiotics) is suboptimal, with high failure rates. As such, there is a clear need for new approaches against H. pylori. Here, we report that Epinecidin-1 (Epi-1) shows effective bactericidal activity against H. Pylori in vitro, and modulates H. Pylori-induced host immune responses in a mouse model. Epi-1 exhibited a low minimum inhibitory concentration (MIC) against antibiotic-sensitive and clinical antibiotic-resistant strains. Moreover, Epi-1 treatment caused 1-N-phenylnaphthylamine (NPN)-fluorescent probe uptake, suggesting it induced membrane lysis; transmission electron micrographs revealed that membranes were destabilized by the generation of saddle-splay membrane curvature. Oral administration of Epi-1 (quaque die dose) in a mouse infection model had strong efficacy (p < 0.00152) against H. pylori, as compared with conventional proton pump inhibitor (PPI)-triple therapeutic antibiotics. Epi-1 inhibited infection through in vivo depletion of CD4+-FOXP3+ T Regulatory and Th17 subset populations, and aided in clearance of persistent H. pylori colonization. Flow cytometry and gene expression analysis of mouse splenic and gastric tissue indicated that Epi-1 inhibits IL-10, and thereby affects FOXP3 expression levels and reduces pro-inflammatory cytokine responses. Crucially, high doses of Epi-1 did not exert toxic effects in oral, dermal, and eye irritation models. Collectively, our results suggest that Epi-1 may be a promising, effective, and safe monotherapeutic agent for the treatment of multi-drug resistant H. pylori infection.

Diagnosis of Helicobacter pylori: What should be the gold standard?

Since the discovery of Helicobacter pylori (H. pylori) in 1983, numerous detection methods for the presence of the bacterium have been developed. Each one of them has been associated with advantages and disadvantages. Noninvasive tests such as serology, ¹³C urea breath test (UBT) and stool antigen tests are usually preferred by the clinicians. Serology has its own limitation especially in endemic areas while ¹³C UBT is technically very demanding. The stool antigen detection method, although specific, is usually associated with poor sensitivity. The ¹³C UBT is believed to be specific, but with present revelation of the fact that stomach is colonized by many other urease producing bacteria makes it questionable. Histology, culture, rapid urease test and polymerase chain reaction (PCR) are the tests which are carried out on antral biopsies collected by invasive means. Histology has been proposed to be very sensitive and specific but the question is how by simply looking the morphology of the bacteria in the microscope, one can claim that the curved bacterium is exclusively H. pylori. Rapid urease test (RUT), the doctor’s test, is also challenged because the presence of other urease producing bacteria in the stomach cannot be denied. Moreover, RUT has been reported with poor sensitivity specially, when density of the bacterium is low. Isolation of H. pylori is essential to investigate its growth requirements, antibiotic susceptibility testing, studying virulence factor to develop vaccine and many more explorations. It has also got several disadvantages i.e., special condition for transporting, media, incubation and few days waiting for the colonies to appear, apart from the speed essentially needed to process the specimens. Till date, majority of the microbiological laboratories in the world are not equipped and trained to isolate such fastidious bacterium. The option left is PCR methods to detect H. pylori’s DNA in gastric mucosa, gastric juice, saliva, dental plaques and environmental specimens. There are speculations for false positivity due to detection of non-pylori Helicobacters due to genetic sharing; and false negativity due to low bacterial counts and presence of PCR inhibitors. However, specimen collection, transportation and processing do not require speed and special conditions. PCR based diagnosis may be considered as gold standard by designing primers extremely specific to H. pylori and targeting at least more than one conserved genes. Similarly specificity of PCR may be improved by use of internal Primers. Further, nested PCR will take care of false negatives by countering the effect of PCR inhibitors and low bacterial counts. Therefore, nested PCR based methods if performed properly, may be proposed as gold standard test.

Non-Invasive Diagnosis of Helicobacter pylori: Evaluation of Two Enzyme Immunoassays, Testing Serum IgG and IgA Response in the Anand District of Central Gujarat,India

CONTEXT

Validation of an accurate and less cumbersome noninvasive method to detect current Helicobacter pylori infection is a requisite for any laboratory.

OBJECTIVES

The purpose of this study is to corroborate the usefulness of two commercially available kits NovaTec ELISA-A and ELISA-G, in the detection of ongoing H.pylori infection.

MATERIALS AND METHODS

Two hundred and twenty eight consecutive serum samples of symptomatic patients who attended the endoscopy unit of "Deep" surgical hospital, Anand, which were collected during the period from 27th February 2008 to 31st august 2011, were studied. The sera were processed and tested for the detection of the H.pylori IgG and IgA antibody by using a solid phase; capture micro well ELISA, procured from Nova Tec immunodiagnostica GmbH Germany.

RESULTS

IgG ELISA showed 100% sensitivity and Negative predictive value (NPV), while IgA ELISA was better in terms of specificity (61.4%) and accuracy (63%) as compared to IgG ELISA. We found 7% (16/228) of IgA positive cases with IgG negative response. IgG response was more common in reflux esophagitis patients (OR 1.451, 95%CI-0.850-2.477) and then in gastritis (OR 0.962, 95%CI-0.570-1.621) and duodenitis(OR-0.806, 95%CI-0.112-5.827), while IgA positive response was more common in duodenitis patients (OR-1.383, 95%CI-0.191-9.995) and reflux esophagitis patients (OR 1.289, 95% CI-0.756-2.197) and least in duodenal ulcer patients (OR 0.670, 95%CI-0.222-2.029).

CONCLUSION

IgG update is reliable and accurate test and can be expedient as a screening test and thus serve as an alternative to endoscopy. For the purpose of excluding infection with H.pylori, the performance of IgG is moderate (low specificity) but can be improved by conjunctional IgA testing which will offer some additional diagnostic value.