Comparison of the serum and salivary antibodies to detect gastric Helicobacter pylori infection in Kashan (Iran)

Frequency and risk factors of H. pylori infection among dental students: an observational cross-sectional study

Despite Helicobacter pylori infection remains asymptomatic in most people, it is associated with an increased risk of gastric cancer. Considering Egypt had the highest prevalence of H. pylori in healthy asymptomatic population in adults and pediatric age in past studies and currently salivary ELISA could be used for diagnosis of Oral H. pylori infection. Moreover, some researchers speculated that dentists and dental students might be at a higher risk for oral H. pylori infection because they are the most frequently exposed ones to saliva and dental plaque. This study aimed to determine risk factors associated with frequency of H. pylori among a sample of dental students for better management of the disease. 83 participants, with age (21-25 years), attending Faculty of Dentistry, Fayoum University were recruited. A structured questionnaire was used to collect information on sociodemographic parameters and risk factors for H. pylori. Direct inquiry about dyspeptic symptoms were done. Saliva samples were collected and tested for H. pylori antibodies. Overall seroprevalence was 22.9%. Participants in internship were more prone to be positive (p = 0.005). 32.6% of urban residents versus 10.8% of rural were H. pylori positive (p = 0.019). 75.0% of previous history of H. pylori infection versus 14.1% of those with no history were H. pylori positive p < 0.001. 70% of positive H. pylori participants reported positive clinical symptoms that were statistically significant. This study suggests that middle income, previous history of H. pylori and clinical symptoms of dyspepsia are risk factors of oral H. pylori with a decline in its prevalence in Egypt.

Diagnostic Testing Accuracy for Helicobacter pylori Infection among Adult Patients with Dyspepsia in Cuba's Primary Care Setting

Evidence of the effectiveness of the tests used to diagnose Helicobacter pylori (H. pylori) in primary healthcare is limited. This cross-sectional study aims to assess the accuracy of tests used for to diagnose H. pylori infection in primary care patients and its relationship with gastroduodenal pathologies. Over 12 months, 173 primary care patients with dyspeptic symptoms were referred for upper gastrointestinal endoscopy to obtain gastric biopsies, and venous blood was extracted from them. H. pylori infection was detected using a rapid urease test (RUT), real-time polymerase chain reaction (RT-PCR), H. pylori-IgG ELISA, and Western blot (WB). The culture and histological findings were used as the reference standard for H. pylori infection. H. pylori prevalence was 50%. There were no significant differences between men and women overall or by age group. The presence of H. pylori was associated with chronic moderate gastritis and its absence with chronic inactive gastritis, as well as the combination of gastritis and gastric lesions (p < 0.05). RUT and ELISA H. pylori -IgG tests showed the highest overall performance (accuracy 98.9% and 84.4%), followed by WB and RT-PCR (accuracy 79.3% and 73.9%). These findings support the notion that combined invasive and noninvasive methods, such as RUT and H. pylori-IgG ELISA, can be a primary diagnostic screening tool for detecting H. pylori among adult dyspeptic patients in Cuba's primary care setting.

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.

First national survey of the diagnosis of Helicobacter pylori infection in Clinical Microbiology Laboratories in Spain

INTRODUCTION

The aim of this study was to know, through a national survey, the methods and techniques used for the diagnosis of Helicobacter pylori (Hp) in the different Clinical Microbiology Services/Laboratories in Spain, as well as antibiotic resistance data.

METHODS

The survey requested information about the diagnostic methods performed for Hp detection in Clinical Microbiology laboratories, including serology, stool antigen, culture from gastric biopsies, and PCR. In addition, the performance of antibiotic susceptibility was collected. Data on the number of samples processed in 2016, positivity of each technique and resistance data were requested. The survey was sent by email (October-December 2017) to the heads of 198 Clinical Microbiology Laboratories in Spain.

RESULTS

Overall, 51 centers from 29 regions answered the survey and 48/51 provided Hp microbiological diagnostic testing. Concerning the microbiological methods used to diagnose Hp infection, the culture of gastric biopsies was the most frequent (37/48), followed by stool antigen detection (35/48), serology (19/48) and biopsy PCR (5/48). Regarding antibiotic resistance, high resistance rates were observed, especially in metronidazole and clarithromycin (over 33%).

CONCLUSION

Culture of gastric biopsies was the most frequent method for detection of Hp, but the immunochromatographic stool antigen test was the one with which the largest number of samples were analyzed. Nowadays, in Spain, it concerns the problem of increased antibiotic resistance to 'first-line' antibiotics.

Diagnosis of Helicobacter pylori infection

The progress this year in Helicobacter pylori diagnosis concerned essentially endoscopy and molecular techniques. New endoscopy techniques such as blue laser imaging and magnifying narrow band imaging allow the visualization of mucosal aspects representing H. pylori infection, intestinal metaplasia, and even ambiguous early gastric cancer. Several real-time PCRs have also been used either to quantify H. pylori or to detect mutations associated with clarithromycin resistance in gastric biopsies or applied on gastric juice, stool specimens, or the oral cavity. The presence of H. pylori in free-living amebae purified from wastewater and drinking water was also determined by PCR and sequencing, as well as culture from a few wastewater samples. Among the noninvasive methods, the urea breath test was used in different conditions, including with a new test meal, which is claimed to avoid the proton-pump inhibitor washout period before testing. Several articles concerning antibody detection and stool antigen test were also published.