Helicobacter pylori diagnostic tests in children: review of the literature from 1999 to 2009

Advances on diagnosis of Helicobacter pylori infections

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

Comparison of Risk and Severity of Helicobacter Pylori Infection in Non-Native Versus US Native Pediatric Patients

Introduction

Helicobacter pylori (HP) infection is associated with gastritis, peptic ulcer disease (PUD) in the stomach and duodenum, and an increased risk of gastric cancer. The risk of infection, secondary symptoms, and negative outcomes is known to be increased in low- and middle-income countries and vastly less substantial in the United States and Europe. Current North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines recommend endoscopic diagnosis and susceptibility-guided therapy, which is not reflected by current adult guidelines for therapy. In this study, we complete a single-center retrospective review of HP risk by nativity status, as well as the results of the use of standard empiric therapy in HP and PUD patients.

Methods

We retrospectively reviewed all endoscopies with patients aged 1-21 years with a known nativity status and identified all HP diagnoses. We also completed the classification of Kyoto scores and classified patients as gastritis versus PUD. Treatment records were obtained, as well as downstream documentation of the impact of empiric therapy. HP prevalence and severity were compared between non-native and native US populations.

Results

In total 332 patients were identified, with 59 HP diagnoses. However, 64 patients were immigrants, and 268 were US natives. Totally 39.1% of all immigrant patients had an endoscopically identified HP infection, compared to only 12.7% of US native patients (P < 0.01, relative risk 3.07). HP severity was worse in immigrant patients (Kyoto score 1.5 versus 0.89; P = 0.008). Empiric high-dose amoxicillin triple therapy was equally effective in reducing symptoms in gastritis versus PUD patients.

Conclusions

Immigrant patients have a substantially higher risk and severity of HP infection than US natives. Empiric therapy remains highly effective at relieving symptoms. These findings in aggregate suggest that North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines may not adequately serve non-native pediatric patients, with an additional prospective multicenter study needed to confirm. In addition, a prospective study of treatment based on stool antigen tests, as well as a larger prospective study of empiric therapy, may suggest alterations to our approach in line with recent changes to adult Gastroenterology practice.

The Importance of Accurate Early Diagnosis and Eradication in Helicobacter pylori Infection: Pictorial Summary Review in Children and Adults

Among the most widespread childhood infections, Helicobacter pylori (H. pylori) develops potentially life-threatening conditions in adults if not appropriately treated. Helicobacter pylori is a common human pathogen that was first described in the stomach many years ago. The discovery of H. pylori was crucial in gastroenterology; this bacterium is associated with chronic gastritis, peptic ulcers, gastric cancer, and lymphoid tissue lymphoma related to the gastric mucosa. Studies published so far estimate that approximately 10% of subjects infected with H. pylori develop a peptic ulcer, and 1-3% of subjects develop gastric cancer. The clinical manifestations are variable and characteristically depend on the individual factors of the host. Various methods of detection and diagnosis of H. pylori infection have been developed, each with advantages, disadvantages, and/or limitations. Available diagnostic tests are usually performed using invasive (endoscopy, biopsy, rapid urease test, cultures, and molecular tests) and noninvasive methods (urea breath test, stool antigen examination, and serological and molecular tests). Although there is extensive accessibility for diagnosing and treating H. pylori infection, the prevalence of antibiotic resistance is not negligible. Thus, numerous studies and meta-analyses are focused on a new orientation of gastroenterologists in diagnosing and treating H. pylori infections. A fascinating perspective hypothesis is the administration of probiotics to reduce H. pylori adhesion to gastric epithelial cells, preventing H. pylori colonization, especially in children, or reinfection with H. pylori in high-risk adult patients.

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.

Detection of A2143G, A2142C, and A2142G Point Mutations with Real-Time PCR in Stool Specimens from Children Infected with Helicobacter pylori

Reports have indicated an increasing prevalence of clarithromycin resistance in children relative to adults. Thus, it is important to investigate primary clarithromycin resistance before therapy to avoid treatment failure. A2142G, A2143G, and A2142C point mutations in the peptidyltransferase region of the 23S ribosomal RNA (rRNA) of Helicobacter pylori (H. pylori) strains isolated from children with gastrointestinal symptoms and asymptomatic children were evaluated via real-time polymerase chain reaction (RT-PCR) using fecal DNA samples. The presence of H. pylori was determined using a fecal H. pylori antigen enzyme-linked immunosorbent assay (ELISA) kit from the stools of children (n = 543). A2143G, A2142C, and A2142G point mutations were detected via RT-PCR and confirmed by sequencing the 23S rDNA. Fecal H. pylori antigen testing was positive in 101 symptomatic (49) and asymptomatic (52) children. A significant difference was found between the 0–5- and 5–18-year-old groups in terms of the A2143G and A2142G point mutations (p = 0.001). The A2142C mutation was not detected. There was a significant difference in the A2143G mutation between the symptomatic and asymptomatic 5–18-year-old children (p = 0.019). Macrolides are frequently used to treat upper respiratory tract infections in children due to their selective pressure effect. We suggest that H. pylori strains carrying mutations in the 23S RNA subunit conferring clarithromycin resistance may lead to an intense inflammatory response in the gastric epithelial cells, allowing them to proliferate more rapidly and causing possible diarrhea, halitosis, or abdominal pain in children.

The relationship between helicobacter pylori infection and nodular antral gastritis in pediatric patients

BACKGROUND

Helicobacter pylori (H. pylori) is a spiral-shaped gram-negative bacterium that colonizes the gastric mucosa. It is a common infectious agent in children. In this study, we aim to evaluate the demographic data, and the clinical and histopathological findings of pediatric patients that underwent upper gastrointestinal endoscopy (UGSE) in our clinic.

METHODS

Between July 2017 and February 2019, 636 patients applied to the Selcuk University Faculty of Medicine, Pediatric Gastroenterology outpatient clinic with complaints of epigastric abdominal pain and/or dyspeptic complaints. Patients who underwent upper gastrointestinal endoscopy were evaluated retrospectively. Data on age, gender, family history of peptic ulcer disease, and family history of H. pylori were recorded. Endoscopic and histopathological findings were collected from medical records.

RESULTS

235 (36.9%) of the patients participating in the study were male, and 401 (63.1%) were female. H. pylori infection was detected in 277 (43.6%) patients as a result of histopathological examination of H. Pylori, urea breath tests and H. Pylori antigen tests in the stools of patients are included in the study. Nodular antral gastritis was detected in 282 (44.3%) of our patients endoscopically. H. pylori was detected in 83.7% (n: 236) of the 282 patients with nodular antral gastritis. Nodular antral gastritis was observed to be significantly higher in H. pylori-positive patients than in H. pylori-negative cases (odds ratio (OR), 39.16; 95% confidence interval (CI), 24.88-61.64; p: <0.001).

CONCLUSION

Nodular antral gastritis is caused by chronic H. pylori infection. It is predicted that early detection of H. pylori infection in children is important and may decrease complications later in life. Our study shows that all the markers evaluated are very good predictors of H. pylori infection. Positive significant association was found between the prevalence of H. pylori infection and nodular antral gastritis.

Helicobacter pylori prevalence in healthy Mexican children: comparison between two non-invasive methods

Background

Helicobacter pylori detection in asymptomatic children with suspected infection or with symptoms that suggest gastric pathology is problematic, since most of the methods depend on the endoscopic study, an invasive and expensive method. Non-invasive methods can be a feasible alternative but must be validated. The purpose of this study was to evaluate the concordance between H. pylori DNA detection in saliva and dental plaque by PCR, with antigen detection in stool by immunochromatography, among asymptomatic children in the state of Guerrero, Mexico.

Methods

Dental plaque, saliva, and stool samples were obtained from 171 children between 6 and 12 years old. H. pylori detection in saliva and dental plaque was performed by PCR using specific primers for the 16S rRNA gene, while the detection in stool samples was performed by immunochromatography using the CerTest kit.

Results

We found an overall H. pylori prevalence of 59.6% (102/171). Of the H. pylori positive children 18% (20/111) were positive in saliva samples, 28.1% (34/121) in dental plaque samples, and 50.4% (71/141) in stool samples. A higher prevalence was found in girls (64.7%, p = 0.002). Although some of the children declared some dyspeptic symptoms, these were no related to H. pylori. In conclusion, we found a high prevalence of H. pylori in asymptomatic children and the highest proportion was detected by stool antigen test, which was the most feasible method to detect H. pylori infection.

What Is New in Helicobacter pylori Diagnosis. An Overview

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

The updated JSPGHAN guidelines for the management of Helicobacter pylori infection in childhood

The Japan Pediatric Helicobacter pylori Study Group published the first guidelines on childhood H. pylori infection in 1997. They were later revised by the Japanese Society for Pediatric Gastroenterology, Hepatology and Nutrition (JSPGHAN). The H. pylori eradication rates, when employing triple therapy with amoxicillin and clarithromycin, currently recommended as the first-line therapy of H. pylori infection in Japan, have substantially decreased, creating an important clinical problem worldwide. In Japanese adults, the "test-and-treat" strategy for H. pylori infection is under consideration as an approach for gastric cancer prevention. However, the combined North American and European pediatric guidelines have rejected such a strategy for asymptomatic children. As risk for gastric cancer development is high in Japan, determining whether the "test-and-treat" strategy can be recommended in children has become an urgent matter. Accordingly, the JSPGHAN has produced a second revision of the H. pylori guidelines, which includes discussion about the issues mentioned above. They consist of 19 clinical questions and 34 statements. An H. pylori culture from gastric biopsies is recommended, not only as a diagnostic test for active infection but for antimicrobial susceptibility testing to optimize eradication therapy. Based upon antimicrobial susceptibility testing of H. pylori strains (especially involving clarithromycin), an eradication regimen including use of the antibiotics to which H. pylori is susceptible is recommended as the first-line therapy against H. pylori-associated diseases. The guidelines recommend against a "test-and-treat" strategy for H. pylori infection for asymptomatic children to protect against the development of gastric cancer because there has been no evidence supporting this strategy.

Prevalence of Helicobacter pylori among children in a training and research hospital clinic in Istanbul and comparison with Updated Sydney Classification Criteria

OBJECTIVE

Helicobacter pylori (H. pylori) is a gram-negative bacterium and one of the reasons for gastritis, peptic and duodenal ulcers. It is a crucial public health problem for both children and adults, especially in developing countries. This study aims to investigate the prevalence of Helicobacter pylori positivity in children and to compare with updated Sydney classification criteria.

METHODS

This study was conducted from January 2015 to June 2017. This study included 885 children aged 0-17 year(s). Endoscopic biopsies were evaluated for the diagnosis of infection due to H. pylori.

RESULTS

The findings showed that 418 (47.2%) of 885 children were positive for H. pylori, and this positivity had a significantly increasing correlation with the presence of chronic inflammation, neutrophilic activity, lymphoid aggregates, and follicles. Erythematous pangastritis and antral nodularity on endoscopic findings had a correlation with H. pylori positivity.

CONCLUSION

In this hospital-based study, the findings suggest that H. pylori infection is a problem for children and more extensive studies are needed to determine the prevalence of H. pylori positivity among children.

Is Routine Preoperative Esophagogastroduodenoscopy Prior to Bariatric Surgery Mandatory? Systematic Review and Meta-analysis of 10,685 Patients

BACKGROUND

This systematic review and meta-analysis searched, retrieved and synthesized the evidence as to whether preoperative esophagogastroduodenoscopy (p-EGD) should be routine before bariatric surgery (BS).

METHODS

Databases searched for retrospective, prospective, and randomized (RCT) or quasi-RCT studies (01 January 2000-30 April 2019) of outcomes of routine p-EGD before BS. STROBE checklist assessed the quality of the studies. P-EGD findings were categorized: Group 0 (no abnormal findings); Group 1 (abnormal findings that do not necessitate changing the surgical approach or postponing surgery); Group 2 (abnormal findings that change the surgical approach or postpone surgery); and Group 3 (findings that signify absolute contraindications to surgery). We assessed data heterogeneity and publication bias. Random effect model was used.

RESULTS

Twenty-five eligible studies were included (10,685 patients). Studies were heterogeneous, and there was publication bias. Group 0 comprised 5424 patients (56%, 95% CI: 45-67%); Group 1, 2064 patients (26%, 95% CI: 23-50%); Group 2, 1351 patients (16%, 95% CI: 11-21%); and Group 3 included 31 patients (0.4%, 95% CI: 0-1%).

CONCLUSION

For 82% of patients, routine p-EGD did not change surgical plan/ postpone surgery. For 16% of patients, p-EGD findings necessitated changing the surgical approach/ postponing surgery, but the proportion of postponements due to medical treatment of H Pylori as opposed to "necessary" substantial change in surgical approach is unclear. For 0.4% patients, p-EGD findings signified absolute contraindication to surgery. These findings invite a revisit to whether p-EGD should be routine before BS, and whether it is judicious to expose many obese patients to an invasive procedure that has potential risk and insufficient evidence of effectiveness. Further justification is required.

Helicobacter pylori Prevalence and Impact: A Histology-Based Report About Children from an Endemic Country

Background

Helicobacter pylori is spreading worldwide with a high prevalence rate in the developing countries. Our primary goal was to measure the histology-based prevalence of Helicobacter pylori infection in children and to quantify its impact on the gastric inflammation and anemia. Our secondary goal was to study possible predictors for the presence of Helicobacter pylori in this cohort.

Methods

A retrospective chart review was performed for children who underwent Esophago-gastro-duodenoscopy at Jordan university hospital in Jordan from 2008 to 2016. Data collected included epidemiological data, indication for endoscopy, endoscopic findings, and laboratory data. The gastric biopsies were re-examined by a pathologist to check for the presence of Helicobacter pylori, the presence of gastritis, and to grade gastritis according to the updated Sydney criteria.

Results

A total of 98 children (53 girls-54%) underwent Esophago-gastro-duodenoscopy. The average age was 11.7 years ± 4.7 years. Of them, 53 patients (29 boys-55%) had Helicobacter pylori identified in the gastric biopsy. The histology-based prevalence rate of Helicobacter pylori was 54%. The most common indication for endoscopy was abdominal pain (53%) followed by vomiting (18%). Nodular gastric mucosa was present in 43% of the Helicobacter pylori-positive group, and in only 11% of the Helicobacter pylori-negative group (P-value <0.0.5). Moderate to severe chronic gastritis was seen in 59% of the biopsies of Helicobacter pylori-positive group, compared to 31% in the Helicobacter pylori-negative group (p value <0.05). Presence of anemia was not different between the two groups (p value > 0.05). Presence of endoscopic nodularity, active gastritis by histology, and moderate to severe gastritis by histology were positive predicators for the presence of Helicobacter pylori. (p value <0.05).

Conclusion

Helicobacter pylori infection in this study cohort of Jordanian children is common, with a histology-based prevalence rate of 54%. Nodularity of the stomach is the most common positive endoscopic feature, and its presence predicts the presence of Helicobacter pylori. Moderate to severe active gastritis is associated with Helicobacter pylori. The presence of Helicobacter pylori does not affect anemia status in this cohort of Jordanian children.

Is routine preoperative esophagogastroduodenscopy prior to bariatric surgery mandatory? protocol for a systematic review and meta-analysis

INTRODUCTION

Routine preoperative esophagogastroduodenscopy (p-EGD) prior to bariatric surgery (BS) is currently widely undertaken, and hence an important issue with many clinical and financial repercussions. Yet, the true extent of why p-EGD is routinely undertaken for all bariatric patients remains not well understood.

METHODS AND ANALYSIS

To address this, we will undertake a systematic review and meta-analysis of routine p-EGD prior to BS from around the world. This protocol describes the methodological approach to be adopted and outlines the search strategies and eligibility criteria that will be employed to identify and select studies, and the way by which data from the selected studies will be extracted for analysis. PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), WHO International Clinical Trials Registry Platform, Cochrane Library, MEDLINE, Scopus, clinicaltrials.gov and Google scholar will be searched from 01 January 2000 to 30 April 2019 for original studies written in English that provided prevalence estimates of the outcomes of routine p-EGD prior to BS. STROBE criteria will assess the methodological quality of the selected studies. The use of fixed or random effects model will depend on the results of statistical tests for heterogeneity. Publication bias will be visually estimated by assessing funnel plots. Pooled estimates will be calculated. This protocol conforms to the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines and has been submitted for registration at the PROSPERO International Prospective Register of systematic reviews. No ethical clearance is required for this study. This review will be published in a peer- reviewed journal and will be presented at various national and international conferences.

Application of Helicobacter pylori stool antigen test to survey the updated prevalence of Helicobacter pylori infection in Taiwan

BACKGROUND AND AIM

The reported prevalence of Helicobacter pylori infection in Taiwan was 54.4% in 1992. An updated prevalence of H. pylori infection in asymptomatic adults is lacking in Taiwan. We aimed to assess the updated age-standardized prevalence of H. pylori infection in asymptomatic subjects and in patients with dyspepsia and to assess the accuracy of H. pylori stool antigen (HpSA) test for screening of H. pylori in Chinese population.

METHODS

Asymptomatic adult subjects (N = 189) were screened for H. pylori infection using HpSA, serology, and ¹³ C-urea breath test (¹³ C-UBT) in 2016-2017. Adult patients with dyspepsia (N = 145) were screened for H. pylori using ¹³ C-UBT, HpSA, serology, rapid urease test, and histology during 2016-2018. Two types of HpSA, including the Diagnostec HpSA ELISA Kit (HpSA ELISA) and Rapid Test Kit (HpSA Rapid), were used in this study. Sensitivity, specificity, and accuracy of the HpSA tests were calculated using the ¹³ C-UBT as golden standard test.

RESULTS

The unadjusted prevalence of H. pylori was 21.2% in asymptomatic adults and 37.9% in patients with dyspepsia (P < 0.001). The age-standardized prevalence of H. pylori was 28.9% in asymptomatic adults in Taiwan. Of the 334 patients included for analysis, the area under the curve of HpSA ELISA test was 0.978, and the optimal cutoff value of optical density was 0.03. The sensitivity, specificity, and accuracy of the HpSA ELISA were 0.929, 0.983, and 0.967, respectively. The sensitivity, specificity, and accuracy of the HpSA Rapid were 0.929, 0.958, and 0.949, respectively.

CONCLUSIONS

The prevalence of H. pylori infection has decreased in Taiwan. HpSA test is an accurate tool for screening of H. pylori in Chinese population.

Diagnosis and treatment of Helicobacter pylori infections in children and elderly populations

Helicobacter pylori (H. pylori) infection is associated with various gastric and extra-gastric diseases. Importantly, this infection is the strongest known risk factor for gastric cancer (GC). H. pylori eradication can effectively prevent H. pylori infection-associated diseases in H. pylori-positive patients, including children and elderly subjects. However, a limited selection of antibiotics, a higher reinfection rate, and certain spontaneous clearance rates, to some extent, restrict the choice of H. pylori treatments in pediatrics. In addition, it is imperative to perform an accurate diagnosis of H. pylori infection in children by determining the presence of the H. pylori infection and the underlying cause of symptoms. In elderly patients, poor tolerance to drugs and higher sensitivity to adverse effects are major concerns during H. pylori therapy. Recent studies have demonstrated that H. pylori eradication could significantly lower the GC risk in the elderly population. The benefit and risk of H. pylori eradication in elderly patients should be comprehensively considered and balanced. If available, susceptibility-based tailored therapies may be preferable in eradicating H. pylori. In addition, to increase the eradication rate and reduce adverse effects, new therapeutic strategies (e.g., probiotic supplementation, berberine supplementation, dual therapy) for H. pylori infection are being extensively investigated. The impact of H. pylori eradication with antibiotics on the microbiota in children has been explored, but further high-quality studies are crucial to delineate the extent of H. pylori eradication affecting the microbial community in children. In this review, we summarize the current understanding of H. pylori diagnosis and treatment in children and the elderly population and aim to provide insights into the efficient management and treatment implementation in these populations.

Epidemiology, Diagnosis and Risk Factors of Helicobacter pylori Infection

Helicobacter pylori is a human-specific pathogen, which leads to gastric pathologies including gastric cancer. It is a highly unique bacterium considered as a carcinogenic agent. H. pylori remains a major human health problem, responsible for ~90% of the gastric cancer cases. Approximately four billion individuals have been detected for H. pylori infection worldwide in 2015. At the turn of the twenty-first century, the prevalence of H. pylori has been declining in highly industrialized countries of the Western world, whereas prevalence has plateaued at a high level in developing and newly industrialized countries. However, the infection status remains high in immigrants coming from countries with high prevalence of H. pylori infection. H. pylori can be diagnosed both by invasive and non-invasive methods. Urea breath test and stool antigens detection are among the most commonly used non-invasive ones. Although the way H. pylori is transmitted remains still not fully clear, the level of contamination is strongly dependent on the familial and environmental context, with a drastic impact of living conditions with poor hygiene and sanitation. However, familial socioeconomic status is the main risk factor for H. pylori infection among children. In addition, food and water source have a high impact on the prevalence of H. pylori infection worldwide. This chapter highlights the latest knowledge in the epidemiology of H. pylori infection, its diagnosis and critical risk factors responsible for its high prevalence in some populations and geographic areas.

Demographics and Clinical and Endoscopic Characteristics of Patients with Helicobacter pylori Infection and Gastroesophageal Reflux Disease: A Case-Control Study

Background

The correlation between Helicobacter pylori (H. pylori) and gastroesophageal reflux disease (GERD) is complex. Some studies showed a protective role of H. pylori infection against GERD. This study was aimed at assessing the role of H. pylori infection in GERD utilizing a large cohort of patients diagnosed with GERD.

Methods and Materials

All patients who underwent gastroscopy for an indication of GERD during the study period between 2015 and 2017 at the EMMS Nazareth Hospital were considered eligible for the study and therefore were included. H. pylori infection was determined by the rapid urease test or histology. Severity of esophagitis was assessed using the Los Angeles classification. Univariate analysis was performed to figure out differences between patients according to H. pylori infection status. Multivariate regression analysis was conducted to illustrate the predictors of positivity for H. pylori infection.

Results

2,508 GERD patients were included with a median age of 49.42 ± 17.96 years. H. pylori infection was detected in 299 (11.9%) patients. GERD patients with H. pylori infection were found to be younger (48.83 ± 17.42 years versus 44.57 ± 17.69 years, p < 0.001), have the tendency to smoke more (1406 (63.6%) versus 266 (89.0%), p < 0.001), and use more proton pump inhibitors or PPIs (1314 (59.5%) versus 242 (80.9%), p < 0.001). In multivariate regression analysis, age (OR 0.987, p < 0.001), smoking status (OR 0.190, p < 0.001), use of ASA/NSAIDs (OR 1.652, p = 0.004), and use of statins (OR 0.499 (95%CI 0.295-0.846), p = 0.010) were found significant among H. pylori-positive individuals. H. pylori-positive subjects have less severe esophagitis and more hiatus hernia.

Conclusion

Patients with GERD and H. pylori infection were significantly younger, tended to smoke more, and used more PPIs and had significantly lower grades of esophagitis compared to noninfected ones.

Performances of the IDEIA HpStAR Stool Antigen Test in Detection of Helicobacter pylori Infection Before and After Eradication Treatment in Algerian Children

We aimed to evaluate in an Algerian pediatric population the diagnostic performances of the IDEIA HpStAR noninvasive stool antigen test (Oxoid, Cambridge, UK) to detect Helicobacter pylori infection before and after eradication therapy. A prospective study including 158 symptomatic Algerian children was conducted. Patients were initially diagnosed with invasive (culture, histology, and rapid urease test) and noninvasive tests (urea breath test and IDEIA HpStAR test). Infected patients were treated, and 101 were controlled after treatment with two invasive (culture and histology) and two noninvasive tests (urea breath test and IDEIA HpStAR test). In Algerian children, the IDEIA HpStAR test showed good performances for initial detection of H. pylori infection and also for subsequent control of eradication treatment. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of IDEIA HpStAR test before treatment were 93.6%, 100%, 100%, 87.3%, and 96%, respectively, and those after treatment were 100, 92.8, 78.6, 100, and 94.2%, respectively.

Helicobacter pylori infection in children: an overview of diagnostic methods

Children differ from adults regarding Helicobacter pylori (H. pylori) infection in many terms. H. pylori infection represents a key factor in the pathogenesis of duodenal ulcer and chronic gastritis in children. H. pylori infection causes some extraintestinal diseases as well as gastrointestinal diseases. Although, among these illnesses in children, symptoms like recurrent abdominal pain are not specific. Moreover, the role of the pathogen in the growth faltering, iron deficiency anemia, and asthma still remains controversial. A reliable method to detect H. pylori infection is a crucial issue, sand is still a matter of active debate. The tests applied for H. pylori diagnosis are grouped as either invasive or non-invasive methods. Invasive methods consist of endoscopic evaluation, the rapid urease test (RUT), histology, and bacterial culture. Non-invasive tests include the urea breath test (UBT), stool antigen test (SAT), serology, and molecular diagnostic approaches. Use of endoscopy is a pre-requisite for all invasive methods and poses difficulties in children as it is a difficult procedure and requires patient's cooperation. For this reason, the non-invasive tests have been commonly used in children, although their accuracy is not very reliable in some cases. Invasive tests may be opted to confirm the diagnosis as and when needed. This review presents the diagnostic tests used to detect H. pylori infection in children.

Helicobacter pylori: a perspective in low- and middle-income countries

BACKGROUND

In adults, Helicobacter pylori is aetiologically associated with peptic ulcer disease and gastric cancer. However, the relationship between this bacteria and gastro-intestinal symptoms in children is less clear.

AIMS

To review the recent literature on H. pylori in children and to outline the approach to diagnosis and management.

METHODS

The English language literature was searched for articles on H. pylori in children. Special attention was paid to prevalence, diagnosis and management pertinent to low- and middle-income countries (LMIC).

RESULTS

Although the prevalence of H. pylori is 60-80% in LMIC, only 5% of infected children develop peptic ulcer disease. The virulence of the organism determines the outcome. There is a suggestion that H. pylori causes iron deficiency anaemia, growth retardation and idiopathic thrombocytopenic purpura, but the evidence is not sufficiently strong to justify screening. There is no evidence to suggest a link between H. pylori infection and recurrent abdominal pain. Endoscopy (with invasive tests) is the preferred method of investigation as the primary goal is to determine the underlying cause of the symptoms. Children with H. pylori-related diseases should be treated with a standard triple-drug regimen consisting of a protein pump inhibitor and two antibiotics for 10-14 days. All treated patients should be monitored for eradication with non-invasive tests such as the urea (13-C) breath test or stool antigen tests.

CONCLUSIONS

Although H. pylori infection is common in LMIC, most children are asymptomatic. There is no association between H. pylori and recurrent abdominal pain. Invasive tests are preferred for diagnosis and a triple-drug regimen is the treatment of choice.

The Diagnostic Tests for Detection of Helicobacter pylori Infection

Helicobacter pylori causes one of the most common infections in human populations. The role of this bacterium in chronic gastritis, gastric ulcer, gastric cancer, as well as extra-digestive diseases such as ischemic heart disease and chronic obstructive pulmonary diseases, is well known. Prevention and control of these diseases can occur by early diagnosis and eradication of H. pylori infection. At present, different methods have been established to detect H. pylori infection. The biopsy-based tests, which are known as invasive methods, such as rapid urease test and histology, have the highest specificity among the others. Similarly, culture of biopsy samples is used for diagnosis of H. pylori infection. It has a high specificity value, and also allows us to perform antibiotic sensitivity testing. On the contrary, polymerase chain reaction and other molecular methods have good sensitivity and specificity, and can be used for detection of H. pylori infection, its virulence factors, and eradication success after treatment. While serological tests are more appropriate for epidemiological studies, their main weakness for clinical use is low specificity. Overall, specificity and sensitivity, cost, usefulness, and limitation of tests should be considered for selection of detection methods of H. pylori in each country.

Accuracy of invasive and noninvasive methods of Helicobacter pylori infection diagnosis in Saudi children

BACKGROUND/AIM

Helicobacter pylori (H. pylori) infection is one of the most common chronic infections in the world. The prevalence of H. pylori is high in Saudi Arabia, but there are no studies in children on the accuracy of invasive and noninvasive methods to diagnose H. pylori infection. The aim of this study was to evaluate the accuracy of six methods for diagnosis of H. pylori infection; four invasive [rapid urease test (RUT), histology, antral nodularity (AD), and biopsy culture (BC)] and two noninvasive methods [serologic test and stool antigen test (SAT)].

PATIENTS AND METHODS

A prospective cross-sectional study was performed among symptomatic children in National Guard hospitals who underwent esophagogastroduodenoscopy from 2010 to 2013. The gold standard diagnosis of H. pylori was positive tissue culture. If the culture was unsuccessful or not done, concordant-positive results for histology and RUT were considered to indicate a positive H. pylori. The variables analyzed as diagnostic methods included RUT, BC, histology, AD, serologic test, and SAT.

RESULTS

A total of 303 children were included in the study. The overall prevalence of H. pylori infection was 49.8%. Most diagnostic tests showed high specificity and moderate-to-low sensitivity when compared to the gold standard test. Sensitivity of AD, SAT, and RUT to detect H. pylori were 62% (95% CI: 0.51-0.74), 69% (95% CI: 0.58-0.79), and 87% (95% CI: 0.79-0.95), respectively (P value 0.040, 0.0023, and <0.0001, respectively). RUT showed the lowest specificity, 65% (95% CI: 0.58-0.71) in contrast to BC and histology which showed moderate-to-high specificities of 88% (95% CI: 0.82-0.95) and 89% (95% CI: 0.82-0.95), respectively (P <0.0001).

CONCLUSION

RUT is a valuable diagnostic method for identifying H. pylori with the highest sensitivity compared to AD and SAT. All diagnostic tests showed moderate-to-high specificities but BC and histology showed the highest specificity.

[Diagnosis of Helicobacter pylori Infection]

Accurate diagnosis of Helicobacter pylori (H. pylori) infection is mandatory for the effective management of many gastroduodenal diseases. Currently, various diagnostic methods are available for detecting these infections, and the choice of method should take into account the clinical condition, accessibility, advantage, disadvantage, as well as cost-effectiveness. The diagnostic methods are divided into invasive (endoscopic-based) and non-invasive methods. Non-invasive methods included urea breath test, stool antigen test, serology, and molecular methods. Invasive methods included endoscopic imaging, rapid urease test, histology, culture, and molecular methods. In this article, we provide a review of the currently available options and recent advances of various diagnostic methods.

When is Helicobacter pylori acquired in populations in developing countries? A birth-cohort study in Bangladeshi children

Helicobacter pylori colonization is prevalent throughout the world, and is predominantly acquired during childhood. In developing countries, >70% of adult populations are colonized with H. pylori and >50% of children become colonized before the age of 10 years. However, the exact timing of acquisition is unknown. We assessed detection of H. pylori acquisition among a birth cohort of 105 children in Mirzapur, Bangladesh. Blood samples collected at time 0 (cord blood), and at 6, 12, 18, and 24 months of life were examined for the presence of IgG and IgA antibodies to whole cell H. pylori antigen and for IgG antibodies to the CagA antigen using specific ELISAs and immunoblotting. Breast milk samples were analyzed for H. pylori-specific IgA antibodies. Cord blood was used to establish maternal colonization status. H. pylori seroprevalence in the mothers was 92.8%. At the end of the two-year follow-up period, 50 (47.6%) of the 105 children were positive for H. pylori in more than one assay. Among the colonized children, CagA prevalence was 78.0%. A total of 58 children seroconverted: 50 children showed persistent colonization and 8 (7.6%) children showed transient seroconversion, but immunoblot analysis suggested that the transient seroconversion observed by ELISA may represent falsely positive results. Acquisition of H. pylori was not influenced by the mother H. pylori status in serum or breastmilk. In this population with high H. pylori prevalence, we confirmed that H. pylori in developing countries is detectable mainly after the first year of life.

Detection of Helicobacter pylori in stool samples of young children using real-time polymerase chain reaction

BACKGROUND

The aims of this study were to develop and validate a multiplex real-time polymerase chain reaction (q-PCR) assay of Helicobacter pylori in stool samples of healthy children. Additionally, we determined the prevalence of clarithromycin resistance and cagA gene in H. pylori-positive samples.

MATERIALS AND METHODS

Archived stool samples from 188 children aged 6-9 years and 272 samples of 92 infants aged 2-18 months were tested for H. pylori antigens using enzyme immunoassay (EIA). A multiplex q-PCR assay was designed to detect H. pylori 16S rRNA and urease and the human RNase P gene as an internal control. Kappa coefficient was calculated to assess the agreement between q-PCR and EIA.

RESULTS

Laboratory validation of the q-PCR assay using quantitated H. pylori ATCC 43504 extracted DNA showed S-shaped amplification curves for all genes; the limit of detection was 1 CFU/reaction. No cross-reactivity with other bacterial pathogens was noted. Applying the multiplex q-PCR to DNA extracted from fecal samples showed clear amplification curves for urease gene, but not for 16S rRNA. The prevalence of H. pylori infection was 50% (95% CI 43%-57%) by q-PCR (urease cycle threshold <44) vs 59% (95% CI 52%-66%) by EIA. Kappa coefficient was .80 (P < .001) and .44 (P < .001) for children aged 6-9 years and 2-18 months, respectively. Sixteen samples were positive for cagA and three were positive for clarithromycin resistance mutation (A2143G) as confirmed by sequencing.

CONCLUSIONS

The developed q-PCR can be used as a cotechnique to enhance the accuracy of H. pylori detection in epidemiological studies and in clinical settings.

Functional Abdominal Pain and Related Syndromes

Functional gastrointestinal disorders are very common. They result from dysfunctional interaction in the brain-gut axis. Although the nature is benign, symptoms may be debilitating. The etiology is multifactorial; therefore, the diagnosis should be approached in a bio-psychosocial model. There are no biomarkers to characterize these conditions, but a solid understanding of the pathophysiology allows providers to present these disorders as a positive clinical diagnosis, rather than a diagnosis of exclusion. Effective management entails close collaboration between the medical and mental health providers.

Detection of Helicobacter pylori in dental plaque using a DNA biosensor for noninvasive diagnosis

H. pylori in dental plaque was detected with a DNA biosensor with results correlating well with the ¹³C urea breath test.

A one-step immune-chromatographic Helicobacter pylori stool antigen test for children was quick, consistent, reliable and specific

AIM

This French study assessed a quick, noninvasive, immuno-chromatographic, Helicobacter pylori (H. pylori) stool antigen test for detecting infections in children.

METHODS

We enrolled 158 children, with a median age of 8.5 years (range eight months to 17 years), with digestive symptoms suggesting upper gastrointestinal tract disease. Upper digestive endoscopy was performed with gastric biopsy specimens for histology, a rapid urease test, culture test and quantitative real-time polymerase chain reaction. The H. pylori stool antigen test was performed twice for each child and the results were compared to the reference method.

RESULTS

The reference methods showed that 23 (14.6%) of the 158 children tested were H. pylori positive. The H. pylori stool antigen test showed 91.3% sensitivity, with a 95% confidence interval (95% CI) of 86.9-95.6 and 97% specificity (95% CI 94.3-99.6), 30.84 positive likelihood ratio and 0.09 negative likelihood ratio. The test accuracy was 96.2% (95% CI 93.2-99.1). The two blinded independent observers produced identical H. pylori stool antigen test results and the Kappa coefficient for the H. pylori stool antigen test was one.

CONCLUSION

The H. pylori stool antigen test was found to be a consistent, reliable, quick and specific test for detecting the H. pylori infection in children.

Is There a Link Between H. Pylori and the Epidemiology of Crohn's Disease?

INTRODUCTION

Case control studies suggest an inverse association between Helicobacter pylori (H. pylori) and Crohn's disease (CD). It is possible this could be accounted for by confounders such as antibiotic therapy. Analyzing the geographic distribution of H. pylori and the links with the incidence and prevalence of CD would be an alternative approach to circumvent these confounders.

METHODS

The literature was searched for studies published between 1990 and 2016 that reported incidence or prevalence data for CD in random population samples in developed countries (GDP per capita >20,000 USD/year). Corresponding prevalence studies for H. pylori in these same regions were then sought matched to the same time period (±6 years). The association between the incidence and prevalence of CD and H. pylori prevalence rates were assessed before and after adjusting for GDP and life expectancy.

RESULTS

A total of 19 CD prevalence and 22 CD incidence studies from 10 European countries, Japan, USA, and Australia with date-matched H. pylori prevalence data were identified. The mean H. pylori prevalence rate was 43.4% (range 15.5-85%), and the mean rates for incidence and prevalence for CD were 6.9 and 91.0/100,000 respectively. The incidence (r = -0.469, p < 0.03) and prevalence (r = -0.527, p = 0.02) of CD was inversely and significantly associated with prevalence of H. pylori infection.

CONCLUSIONS

Our data demonstrate a significant inverse association between geographic distribution of H. pylori and CD. Thus, it is highly unlikely that the findings of previous case control studies were simply due to confounding factors such as concomitant antibiotic use in CD patients.

Joint ESPGHAN/NASPGHAN Guidelines for the Management of Helicobacter pylori in Children and Adolescents (Update 2016)

BACKGROUND

Because of the changing epidemiology of Helicobacter pylori infection and low efficacy of currently recommended therapies, an update of the European Society for Paediatric Gastroenterology Hepatology and Nutrition/North American Society for Pediatric Gastroenterology, Hepatology and Nutrition recommendations for the diagnosis and management of H pylori infection in children and adolescents is required.

METHODS

A systematic review of the literature (time period: 2009-2014) was performed. Representatives of both societies evaluated the quality of evidence using GRADE (Grading of Recommendation Assessment, Development, and Evaluation) to formulate recommendations, which were voted upon and finalized using a Delphi process and face-to-face meeting.

RESULTS

The consensus group recommended that invasive diagnostic testing for H pylori be performed only when treatment will be offered if tests are positive. To reach the aim of a 90% eradication rate with initial therapy, antibiotics should be tailored according to susceptibility testing. Therapy should be administered for 14 days, emphasizing strict adherence. Clarithromycin-containing regimens should be restricted to children infected with susceptible strains. When antibiotic susceptibility profiles are not known, high-dose triple therapy with proton pump inhibitor, amoxicillin, and metronidazole for 14 days or bismuth-based quadruple therapy is recommended. Success of therapy should be monitored after 4 to 8 weeks by reliable noninvasive tests.

CONCLUSIONS

The primary goal of clinical investigation is to identify the cause of upper gastrointestinal symptoms rather than H pylori infection. Therefore, we recommend against a test and treat strategy. Decreasing eradication rates with previously recommended treatments call for changes to first-line therapies and broader availability of culture or molecular-based testing to tailor treatment to the individual child.

Epidemiology, Diagnosis, and Risk Factors of Helicobacter pylori Infection in Children

H. pylori infection is a global public health problem associated with some gastrointestinal diseases in children, especially in developing countries, since prevalence of H. pylori is low in the developed world. Both noninvasive (stool antigen test, urea breath test, and blood test) and invasive (histology, rapid urease test, and microbiological culture) tests have been utilized to detect H. pylori infection. However, a single test is not reliable enough and does not provide accurate enough data to determine H. pylori infection among children. Risk factors of H. pylori infection in children were related to ethnicities, household properties, geographic location, living conditions, water sources, type of housing, presence/absence of sewage systems, and garbage collection within the living environment. These risk factors were usually associated with the socioeconomic status of the family. This review article aims to determine the gaps in the knowledge of the epidemiology, risk factors, and diagnostic tests of H. pylori infection among children.

How to cite this article: Ozbey G, Hanafiah A. Epidemiology, Diagnosis, and Risk Factors of Helicobacter pylori Infection in Children. Euroasian J Hepato-Gastroenterol 2017;7(1):34-39.

Helicobacter pylori serology testing is a useful diagnostic screening tool for symptomatic inner city children

AIM

This study assessed the Helicobacter pylori (H. pylori) serum antibody test as a diagnostic screening tool in symptomatic inner city children.

METHODS

This was a retrospective study of patients aged one to 18 years who were referred to our paediatric gastroenterology department from 2009 to 2013. We included all patients who had H. pylori serum antibodies and/or faecal antigens who underwent esophagogastroduodenoscopy (EGD) for histology, with or without a gastric tissue rapid urease test.

RESULTS

A total of 395 patients had EGDs carried out to evaluate epigastric pain, heartburn and nausea or vomiting, and their overall socio-economic Z-score was -2.62. The histology was positive for H. pylori infection in 52 of 395 patients (13%), and epigastric pain was documented in 45 of these 52 patients (87%). Compared to histology, the serum H. pylori antibody test had a sensitivity of 88.4% and a specificity of 93.4%. The tissue rapid urease test and faecal antigen test had sensitivities of 89.3% and 55.6% and specificities of 89.9% and 98.9%, respectively.

CONCLUSION

The serum H. pylori antibody test had high sensitivity and specificity, and it was a good diagnostic screening tool in our study. Epigastric pain was strongly associated with a current H. pylori infection in our population.

Investigation of Helicobacter pylori infection among symptomatic children in Hangzhou from 2007 to 2014: a retrospective study with 12,796 cases

Background and Aim

The infection of Helicobacter pylori (H. pylori) is acquired in childhood and the prevalence vary greatly in different countries and regions. The study aimed to investigate the characteristics of H. pylori infection among children with gastrointestinal symptoms in Hangzhou, a representative city of eastern China.

Methods

A systematic surveillance of H. pylori infection according to the ¹³C-urea breath test was conducted from January 2007 to December 2014 in the Children’s hospital, Zhejiang University School of Medicine. The demographic information and main symptoms of every subject were recorded.

Results

A total of 12,796 subjects were recruited and 18.6% children evaluated as H. pylori positive. The annual positive rates decreased from 2007 to 2014 (χ² = 20.461, p < 0.01). The positive rates were 14.8%, 20.2% and 25.8% in 3–6, 7–11 and 12–17 years age group respectively, which increased with age (χ² = 116.002, p < 0.01). And it was significantly higher in boys than girls (χ² = 15.090, p < 0.01). Multivariate logistic regression identified possible risk factors for H. pylori infection. Age, gender, gastrointestinal symptoms and history of H. pylori infected family member were all significantly associated with H. pylori infection (all p < 0.05).

Conclusions

H. pylori infection rates in children with gastrointestinal symptoms were lower than most of those reported in mainland China. Further studies are required to determine the prevalence in the general population. Comprehensively understanding of the characteristics and the possible risk factors of H. pylori infection will be helpful to its management strategies in children in China.

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.

Updates on the Diagnosis of Helicobacter pylori Infection in Children: What Are the Differences between Adults and Children?

Helicobacter pylori infection is acquired mainly during childhood and causes various diseases such as gastritis, peptic ulcer disease, mucosa-associated lymphoid tissue (MALT) lymphoma, and iron deficiency anemia. Although H. pylori infection in children differs from adults in many ways, this is often overlooked in clinical practice. Unlike adults, nodular gastritis may be a pathognomonic endoscopic finding of childhood H. pylori infection. Histopathological findings of gastric tissues are also different in children due to predominance of lymphocytes and plasma cells and the formation of gastric MALT. Although endoscopy is recommended for the initial diagnosis of H. pylori infection, several non-invasive diagnostic tests such as the urea breath test (UBT) and the H. pylori stool antigen test (HpSA) are available and well validated even in children. According to recent data, both the (13)C-UBT and HpSA using enzyme-linked immunosorbent assay are reliable non-invasive tests to determine H. pylori status after eradication therapy, although children younger than 6 years are known to have high false positives. When invasive or noninvasive tests are applied to children to detect H. pylori infection, it should be noted that there are differences between children and adults in diagnosing H. pylori infection.

Limitations of urease test in diagnosis of pediatric Helicobacter pylori infection

The diagnosis of Helicobacter pylori (H. pylori) infection is usually based on the results of urease test and histology. The urease test known as a simple and cheap method does not need special skills to perform or to read the result. The time needed for the test to turn positive depends on the concentration of bacteria, and the accuracy is up to the density of H. pylori density in the biopsy sample, which is generally lower in children than adolescents and adults. Therefore, there are debates about the sensitivity of the urease test in children. The reason for lower sensitivity of the urease test in children was not identified, but might be related to the low density and patchy distribution of bacteria. In this review, we discuss the limitations of the urease test in children according to age, histology, number of biopsy samples, and biopsy site. In children under 5 years old, the differences in positivity rate when the urease test used one or three biopsy samples, and samples from the antrum or the gastric body, were larger than those in children aged 5-15 years. Thus, three or more biopsy samples from both the antrum and body would improve the sensitivity of H. pylori infection diagnosis in children under 5 years old.

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.

Loop-Mediated Isothermal Amplification as a Fast Noninvasive Method of Helicobacter pylori Diagnosis

BACKGROUND

Helicobacter pylori infection is etiologically associated with some important health problems such as gastric cancer. Because of the high clinical importance of H. pylori infection, development of a noninvasive test for the detection of H. pylori is desirable.

METHODS

In this study, a loop-mediated isothermal amplification (LAMP) targeted ureC of H. pylori was evaluated on 100 stool specimens and compared with a stool antigen test. Culture and rapid urease test were considered as gold standards.

RESULTS

The overall detection rate of the fecal antigen test and LAMP was 58% and 82%, respectively. The analytical sensitivity of the fecal antigen test and LAMP was 500 and 10 H. pylori cells/g and 10 fg DNA/reaction, which is equal to six H. pylori genome.

CONCLUSION

LAMP technique has been characterized by high sensitivity and low detection limit for the detection of H. pylori in stool specimen. Clinical diagnostic performance of LAMP was better than the stool antigen test.

Usefulness of Gastric Biopsy-Based Real-Time Polymerase Chain Reaction for the Diagnosis of Helicobacter pylori Infection in Children

OBJECTIVES

The aim of the study was to assess the usefulness of gastric biopsy-based quantitative real-time polymerase chain reaction (qPCR) for the detection of Helicobacter pylori infection and the identification of clarithromycin-resistant strains in children.

METHODS

A gastric biopsy-based qPCR for the detection of H pylori infection and the identification of clarithromycin-resistant strains in children was evaluated in 62 children with infection and 341 children without infection. H pylori infection was considered by the "reference method" when culture was positive for both histology and rapid urease test (RUT). Results were compared with those obtained using the qPCR.

RESULTS

The reference method versus H pylori qPCR positivity showed 95% confidence interval sensitivity 100% versus 100%, specificity 93.2% (86.9-99.4) versus 100%, positive predictive value 59.7% (47.4-71.9) versus 100%, negative predictive value 100% versus 100%, and, finally, test accuracy of 59.6% (47.3-71.8) versus 100%. Sixty-two children were found to be H pylori positive, based on the qPCR results. Among those, 31 children had both positive qPCR and culture with concordant antimicrobial susceptibility testing results, whereas 31 children had negative culture and positive qPCR. The qPCR showed a bacterial load ≥10 copies per milliliter when culture, histology, and RUT were all positive (29/31 children) versus <10 copies per milliliter when culture, histology, and RUT were all negative (25/31 children). Grades 2 and 3 histological gastritis were associated with a bacterial load ≥10 copies per milliliter for 28/35 of children versus 27/27 of grade 0 to 1 <10 copies per milliliter.

CONCLUSIONS

H pylori qPCR positivity is a more precise test than the routine culture, histology, RUT alone and allows detecting low bacterial loads.

Comparison of Serum IgG Antibody Test with Gastric Biopsy for the Detection of Helicobacter Pylori Infection among Egyptian Children

BACKGROUND:

In developing countries, Helicobacter pylori (H. pylori) infection is mainly acquired during childhood and may be a predisposing factor for peptic ulcer or gastric cancer later in life. Noninvasive diagnostic tools are particularly useful in children for screening tests and epidemiological studies. Data on serologic testing of children are lacking. Accurate noninvasive tests for diagnosing Helicobacter pylori infection in children are strongly required.

AIM:

The aim of this study was to evaluate the performance of a serological test (serum IgG antibody for H. pylori) in Egyptian children with recurrent abdominal pain necessitating endoscopy.

SUBJECTS AND METHODS:

One hundred children, referred to the endoscopy unit at Mansoura University. Upper endoscopy was done for each with rapid urease test (RUT) and histological examination as the gold standard test for detection of H. pylori infection. Serum samples were collected for detecting IgG for H. pylori infection.

RESULTS:

The mean age of the subjects included in the study was 7.23 ± 1.94 year. Serological test (IgG to H. pylori) was positive in 60% of all cases. A highly significant association between the standard test and the serological test at a cutoff > 10 U/ml at p = 0.001 were detected for the diagnosis of H. pylori infection. The sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio for the IgG antibody a cutoff > 10 U/ml, were 96.5%, 93%, 13.83, 0.038 respectively.

CONCLUSION:

Serum IgG antibody to H. pylori infection has a high diagnostic value and can be considered as a suitable and reliable noninvasive test for detection of H. pylori infection.

Isolation and diagnosis of Helicobacter pylori by a new method: Microcapillary culture

AIM: To investigate the performance of the microcapillary culture method (MCM) in Helicobacter pylori (H. pylori) isolation and diagnosis.

METHODS: Microcapillary culture (MC), classical culture (CC), rapid urease (CLO) test, and histopathologic examination (HE) were performed with biopsy samples. Homogenized biopsy samples were loaded into capillary tubes and incubated for 48 h at 37 °C without providing a microaerophilic environment. Additionally, three or four loops of the homogenized sample were inoculated in a ready-to-use selective medium (Becton Dickinson, Helicobacter Agar, Modified) specific for the isolation of H. pylori and incubated at 37 °C in a microaerophilic atmosphere provided by CampyGen (Becton Dickinson, GasPack). Bacteria reproducing in microcapillary tubes were evaluated in an inverted microscope and also were evaluated after performing a CC with the content. Results obtained by CC, CLO test, and HE were compared with those of MC. The diagnostic performances of the methods used in this study were evaluated for specificity, sensitivity, positive predictive value (PPV), negative predictive value (NPV), and CI.

RESULTS: H. pylori was found positive by CLO test + HE and/or CC culture in 26 patient antrum and corpus biopsy samples. In 25 (25/26) patient biopsy samples, H. pylori was isolated by MCM, whereas in only 14 (14/26) patient biopsy samples, H. pylori was isolated by CC. CLO test and HE were found positive in 17 (17/26) patient biopsy samples. Comparing the results of the isolation of H. pylori by MCM, CC, CLO test, and HE, the sensitivity of the MCM was found as 96%, the specificity as 80%, the PPV as 83%, the NPV as 95%, and the 95%CI as 0.76 (χ² = 31.51, P < 0.01) whereas the sensitivity of the CC was found as 54% (χ² = 19.15, P < 0.01), and the sensitivity of the CLO test and HE were found as 65% (χ² = 25.26, P < 0.01).

CONCLUSION: This new microcapillary cultivation method for H. pylori has high diagnostic sensitivity compared with CC, HE, and CLO tests.

A 15-year-old boy with abdominal pain, growth retardation, and anemia secondary to Helicobacter pylori-associated peptic ulcer

A 15-year-old boy with abdominal pain, growth retardation, and symptomatic anemia requiring blood transfusion was seen by a gastroenterologist and found to have a large ulcerated, fungating, and actively bleeding mass in his stomach. Initially, the patient was screened for Helicobacter pylori and found to be negative, so there was concern for malignancy after multiple endoscopic procedures. The patient did not respond to initial ulcer treatment and immediately prior to scheduled partial gastrectomy, additional tissue sections from the initial biopsy were stained for H. pylori and rare positive staining organisms were found. The test was positive, and the patient was started empirically on treatment to which he responded and ultimately recovered fully. Gastrectomy was not performed, and following treatment, the ulcer, anemia, and poor growth resolved.

Prevalence and risk factors of Helicobacter pylori infection in Saudi children: a three-year prospective controlled study

BACKGROUND

Helicobacter pylori (H. pylori) infection is the most common chronic infections. The risk factors for H. pylori infection in both developing and developed countries are closely related to poor living conditions in childhood. This study aimed to establish the prevalence of H. pylori infection and its associated risk factors among children in the western and central regions of Saudi Arabia.

METHODS

A prospective cross-sectional study was performed among symptomatic children in National Guard hospitals who underwent esophagogastroduodenoscopy from 2010 to 2013. The gold standard diagnosis of H. pylori infection was histologic presence of the bacteria in the gastric biopsy. The variables analyzed as possible risk factors included demographic and living characteristics, socioeconomic status, potential mode of transmission, and clinical indications of H. pylori infection.

RESULTS

A total of 303 children were included in the study. The overall prevalence of H. pylori infection was 49.8%. Among the studied variables, the following were positively associated with the presence of H. pylori in multivariable analyses: age above 10 years(OR = 11.84, 95% CI = 3.90-35.94, p < .0001), an income of <5000 SR (OR = 2.06, 95% CI = 1.07-3.95), more than eight persons in the household (OR = 3.46, 95% CI = 1.67-7.20), bed sharing (OR = 2.26, 95% CI = 1.32-3.86), and two affected parents (OR = 11.19, 95% CI = 1.29-97.27). Abdominal pain and anorexia were significant predictors of H. pylori infection (p = .005 and .009, respectively).

CONCLUSION

Helicobacter pylori infection had a high prevalence among Saudi children in the cities of Jeddah and Riyadh. It was a relatively common cause of abdominal pain and anorexia. In this cohort of children, H. pylori infection was associated with variables indicative of a crowded environment and poor living conditions, further supporting the conclusion that improving socioeconomic conditions and designing a preventive health strategy in Saudi Arabia will likely protect children against this infection.

Helicobacter pylori infection in Omani children

BACKGROUND

Helicobacter pylori (H. pylori) infection is the most common chronic bacterial infection in humans. Its prevalence in Omani adults and children is not known.

OBJECTIVE

To report histology-based H. pylori infection prevalence in Omani children.

METHODS

A retrospective study of biopsy proven H. pylori infection in children over a 3 year period in a single center. Age, gender, indication for endoscopy, history of recurrent abdominal pain, and anemia were compared between H. pylori-positive and negative children.

RESULTS

Of 143 patients who underwent endoscopy, gastric biopsies were available on 112. The overall prevalence of biopsy proven H. pylori infection was 25%. The prevalence in children with recurrent abdominal pain was 30% compared to 22% in children who underwent endoscopy for other indications (p = .382). The prevalence increased from 7% in children aged <5 years, to 33% in those aged between 5 and 10 years (p = .010). There was no significant difference in the prevalence between the 5-10 years age group (33%) and older age group (29%) (p = .814). There was no significant difference in gender or anemia between the two groups.

CONCLUSIONS

This study represents the first reported study on the prevalence of biopsy proven H. pylori infection in Omani children. H. pylori infection prevalence is 25%, is lower than regional and many Arab countries. The prevalence appears to increase till age of 5 years. There was no significant association between H. pylori and recurrent abdominal pain, gender, or anemia.

Helicobacter pylori infection - recent developments in diagnosis

Considering the recommended indications for Helicobacter pylori (H. pylori) eradication therapy and the broad spectrum of available diagnostic methods, a reliable diagnosis is mandatory both before and after eradication therapy. Only highly accurate tests should be used in clinical practice, and the sensitivity and specificity of an adequate test should exceed 90%. The choice of tests should take into account clinical circumstances, the likelihood ratio of positive and negative tests, the cost-effectiveness of the testing strategy and the availability of the tests. This review concerns some of the most recent developments in diagnostic methods of H. pylori infection, namely the contribution of novel endoscopic evaluation methodologies for the diagnosis of H. pylori infection, such as magnifying endoscopy techniques and chromoendoscopy. In addition, the diagnostic contribution of histology and the urea breath test was explored recently in specific clinical settings and patient groups. Recent studies recommend enhancing the number of biopsy fragments for the rapid urease test. Bacterial culture from the gastric biopsy is the gold standard technique, and is recommended for antibiotic susceptibility test. Serology is used for initial screening and the stool antigen test is particularly used when the urea breath test is not available, while molecular methods have gained attention mostly for detecting antibiotic resistance.

Diagnosis of Helicobacter pylori infection by invasive and noninvasive tests

Although several invasive and noninvasive tests have been developed for the diagnosis of Helicobacter pylori infection, all of the tests have their limitations. We conducted a study to investigate and compare the suitability of rapid urease test (RUT), serology, histopathology and stool antigen tests with polymerase chain reaction (PCR) for detection of H. pylori, and correlate the diagnostic methods with PCR. Eighty nine patients (61 adults, 28 children) referred to the Firoozgar Hospital and Children Medical Center Hospital for diagnostic upper gastrointestinal endoscopy entered to the study and noninvasive tests such as immunoassay for serological antibodies against H. pylori and detection of its antigen in feces were measured. The biopsies were utilized for histological examination, RUT and PCR. The H. pylori statuses were evaluated by the positivity of ureC PCR in biopsy specimens and 53 subjects had H. pylori positive result. Histopathology showed high overall performance in adults and children with sensitivity and specificity 100% and 90%, respectively. Sensitivity, specificity, and accuracy for stool antigen test were 87.8%, 75% and 82%, respectively. Correlation of RUT, serology (IgG), histopathology and stool antigen tests with PCR were 0.82, 0.32, 0.91 and 0.63, respectively. In conclusion, the RUT and histopathology are as accurate as the PCR of biopsy and stool antigen test can consider as appropriate noninvasive test for detection of H. pylori infection.