Intraprocedural gastric juice analysis as compared to rapid urease test for real-time detection of Helicobacter pylori

BACKGROUND Endofaster is an innovative technology that can be combined with upper gastrointestinal endoscopy(UGE)to perform gastric juice analysis and real-time detection of Helicobacter pylori(H.pylori).AIM To assess the diagnostic performance of this technology and its impact on the management of H.pylori in the real-life clinical setting.METHODS Patients undergoing routine UGE were prospectively recruited.Biopsies were taken to assess gastric histology according to the updated Sydney system and for rapid urease test(RUT).Gastric juice sampling and analysis was performed using the Endofaster,and the diagnosis of H.pylori was based on real-time ammonium measurements.Histological detection of H.pylori served as the diagnostic gold standard for comparing Endofaster-based H.pylori diagnosis with RUT-based H.pylori detection.RESULTS A total of 198 patients were prospectively enrolled in an H.pylori diagnostic study by Endofasterbased gastric juice analysis(EGJA)during the UGE.Biopsies for RUT and histological assessment were performed on 161 patients(82 men and 79 women,mean age 54.8±19.2 years).H.pylori infection was detected by histology in 47(29.2%)patients.Overall,the sensitivity,specificity,accuracy,positive predictive value,and negative predictive value(NPV)for H.pylori diagnosis by EGJA were 91.5%,93.0%,92.6%,84.3%,and 96.4%,respectively.In patients on treatment with proton pump inhibitors,diagnostic sensitivity was reduced by 27.3%,while specificity and NPV were unaffected.EGJA and RUT were comparable in diagnostic performance and highly concordant in H.pylori detection(κ-value=0.85).CONCLUSION Endofaster allows for rapid and highly accurate detection of H.pylori during gastroscopy.This may guide taking additional biopsies for antibiotic susceptibility testing during the same procedure and then selecting an individually tailored eradication regimen.

Dual specimens increase the diagnostic accuracy and reduce the reaction duration of rapid urease test

AIM:To evaluate the influence of multiple samplings during esophagogastr oduodenoscopy(EGD) on the accuracy of the rapid urease test,and the validity of newly developed rapid urease tests,HelicotecUT plus test and HelicotecUT test,CLO test and ProntoDry test.METHODS:A total of 355 patients undergoing EGD for dyspepsia were included.Their Helicobacter pylori(H.pylori) treatment status was either nave or eradicated.Six biopsy specimens from antrum and gastric body,respectively,were obtained during EGD.Single antral specimens and dual(antrum+body) specimens were compared.Infection status of H.pylori was evaluated by three different tests:culture,histology,and four different commercially available rapid urease tests(RUTs)-including the newly developed HelicotecUT plus test and HelicotecUT test,and established CLO test and ProntoDry test.H.pylori status was defined as positive when the culture was positive or if there were concordant positive results among histology,CLO test and ProntoDry test.RESULTS:When dual specimens were applied,sensitivity was enhanced and RUT reaction time was signif icantly reduced,regardless of their treatment status.Thirty minutes were enough to achieve an agreeable positive rate in all the RUTs.Both newly developed RUTs showed comparable sensitivity,specif icity and accuracy to the established RUTs,regardless of patient treatment status,RUT reaction duration,and EGD biopsy sites.CONCLUSION:Combination of antrum and body biopsy specimens greatly enhances the sensitivity of rapid urease test and reduces the reaction duration to 30 min.

Evaluation of the use of rapid urease test:Pronto Dry to detect H pylori in patients with dyspepsia in several cities in Indonesia

AIM： To evaluate Pronto Dry examination in patients with dyspepsia. METHODS： The study was conducted in patients with dyspepsia who underwent endoscopic examination in several endoscopic centers of several cities in Indonesia from January 2003 until April 2004. Biopsies for histopathologic examination were fixed with formalin and sent to Histopathologic Department to be analyzed and confirm the presence of Hpylori infection. If Hpylori was found positive, the density was calculated semi quantitatively. Histopathologic examination from gastric biopsy samples was interpreted based on the updated Sydney system classification. RESULTS： Of 550 patients, 309 （56%） were male and 241 （44%） were female with ages ranging from 15 to 82 years. Mean age was 44.98 ± 14.46 years. Mean age of male patients was 44.35 ± 13.85 years and mean age of female patients was 45.78± 15.19 years. Evaluation of endoscopic results showed gastric ulcer in 36 cases （6.5%） and duodenal ulcer in 20 cases （3.6%）. Normal endoscopic finding was found in 45 cases （8.2%） and minimal disorder of gastritis and duodenitis were found in 246 cases （44.7%）. One case of gastric cancer was identified. Of 56 cases which were positive based on the criteria used, 39 patients were positive with Pronto Dry and 17 patients were negative with Pronto Dry. Overall sensitivity and specificity of Pronto Dry were 69.7% and 95.7% respectively. Positive predictive value was 66.1% and negative predictive value was 96.4% and overall accurate rate was 92.9%. CONCLUSION： Pronto Dry seems promising as a diagnostic tool to detect Hpy/ori more rapidly and accurately.

Rapid Urease Test and Faecal Antigen Detection for Rapid Diagnosis of Helicobacter pylori Infection in Dyspepsia

Background: Helicobacter pylori (H. pylori) is considered as one of the most prevalent gastric infections which cause chronic gastritis and predispose to cancer stomach. So, diagnosis and eradication should be rapid to decrease the risk of gastric cancer. Aim of the study: To evaluate the role of rapid urease test (RUT) and faecal antigen test (FAT) added to serological test for rapid diagnosis of active H. pylori infection. Patients and methods: 270 patients with dyspepsia and positive serology for H. pylori infection were included. Two antral and two corporal gastric biopsies were taken for RUT and Histopathological examination. Fresh stool samples were obtained from all patients for FAT. Results: The mean age of the studied patients was 45 ± 25. H. pylori infection was found in 256 (94.8%) of the included patients: 236 (92.18%) with positive all tests, 5 (1.95%) with positive both RUT and FAT, 8 (3.12%) with positive both histology and RUT and 7 (2.73%) with positive histology and FAT. The sensitivity, specificity and positive predictive values for RUT were as follows: 97.27%, 85.71% and 99.20% respectively and 96.88%, 85.71% and 99.20% respectively for FAT. Conclusions: RUT or FAT in patients with positive serological test could be used for rapid diagnosis of active H. pylori infection with good sensitivity and specificity without waiting for the results of histology or culture.

Retrospective analysis of discordant results between histology and other clinical diagnostic tests on helicobacter pylori infection

BACKGROUND A reliable test is essential for diagnosing Helicobacter pylori(H.pylori)infection,and crucial for managing H.pylori-related diseases.Serving as an excellent method for detecting H.pylori infection,histologic examination is a test that clinicians heavily rely on,especially when complemented with immunohistochemistry(IHC).Additionally,other diagnostic tests for H.pylori,such as the rapid urease test(CLO test)and stool antigen test(SA),are also highly sensitive and specific.Typically,the results of histology and other tests align with each other.However,on rare occasions,discrepancy between histopathology and other H.pylori diagnostic tests occurs.AIM To investigate the discordance between histology and other H.pylori tests,the underlying causes,and the impact on clinical management.METHODS Pathology reports of gastric biopsies were retrieved spanning August 2013 and July 2018.Reports were included in the study only if there were other H.pylori tests within seven days of the biopsy.These additional tests include CLO test,SA,and H.pylori culture.Concordance between histopathology and other tests was determined based on the consistency of results.In instances where histology results were negative while other tests were positive,the slides were retrieved for re-assessment,and the clinical chart was reviewed.RESULTS Of 1396 pathology reports were identified,each accompanied by one additional H.pylori test.The concordance rates in detecting H.pylori infection between biopsy and other tests did not exhibit significant differences based on the number of biopsy fragments.117 discrepant cases were identified.Only 20 cases(9 with CLO test and 11 with SA)had negative biopsy but positive results in other tests.Four cases initially stained with Warthin-Starry turned out to be positive for H.pylori with subsequent IHC staining.Among the remaining 16 true discrepant cases,10 patients were on proton pump inhibitors before the biopsy and/or other tests.Most patients underwent treatment,except for two who were untreated,and two patients who were lost to follow-up.CONCLUSION There are rare discrepant cases with negative biopsy but positive in SA or CLO test.Various factors may contribute to this inconsistency.Most patients in such cases had undergone treatment.

Value of a new stick-type rapid urine test for the diagnosis of Helicobacter pylori infection in the Vietnamese population

AIM: To assess the value of a new test for the diagnosis of Helicobacter pylori (H. pylori) infection, Rapirun®H. pylori Antibody Stick (Rapirun® Stick), in a Vietnamese population.

Helicobacter pylori in gastric cancer: Features of infection and their correlations with long-term results of treatment

BACKGROUND Helicobacter pylori(H.pylori)is a spiral-shaped bacterium responsible for the development of chronic gastritis,gastric ulcer,gastric cancer(GC),and MALTlymphoma of the stomach.H.pylori can be present in the gastric mucosa(GM)in both spiral and coccoid forms.However,it is not known whether the severity of GM contamination by various vegetative forms of H.pylori is associated with clinical and morphological characteristics and long-term results of GC treatment.AIM To establish the features of H.pylori infection in patients with GC and their correlations with clinical and morphological characteristics of diseases and long-term results of treatment.METHODS Of 109 patients with GC were included in a prospective cohort study.H.pylori in the GM and tumor was determined by rapid urease test and by immunohistochemically using the antibody to H.pylori.The results obtained were compared with the clinical and morphological characteristics and prognosis of GC.Statistical analysis was performed using the Statistica 10.0 software.RESULTS H.pylori was detected in the adjacent to the tumor GM in 84.5%of cases,of which a high degree of contamination was noted in 50.4%of the samples.Coccoid forms of H.pylori were detected in 93.4%of infected patients,and only coccoid-in 68.9%.It was found that a high degree of GM contamination by the coccoid forms of H.pylori was observed significantly more often in diffuse type of GC(P=0.024),in poorly differentiated GC(P=0.011),in stage T3-4(P=0.04)and in N1(P=0.011).In cases of moderate and marked concentrations of H.pylori in GM,a decrease in 10-year relapse free and overall survival from 55.6%to 26.3%was observed(P=0.02 and P=0.07,respectively).The relationship between the severity of the GM contamination by the spiral-shaped forms of H.pylori and the clinical and morphological characteristics and prognosis of GC was not revealed.CONCLUSION The data obtained indicates that H.pylori may be associated not only with induction but also with the progression of GC.

Establishment of a nested-ASP-PCR method to determine the clarithromycin resistance of Helicobacter pylori

AIM: To investigate clarithromycin resistance positions 2142, 2143 and 2144 of the 23 Sr RNA gene in Helicobacter pylori(H. pylori) by nested-allele specific primer-polymerase chain reaction(nested-ASP-PCR).METHODS: The gastric tissue and saliva samples from 99 patients with positive results of the rapid urease test(RUT) were collected. The nested-ASP-PCR method was carried out with the external primers and inner allele-specific primers corresponding to the reference strain and clinical strains. Thirty gastric tissue and saliva samples were tested to determine the sensitivity of nested-ASP-PCR and ASP-PCR methods. Then, clarithromycin resistance was detected for 99 clinical samples by using different methods, including nestedASP-PCR, bacterial culture and disk diffusion. RESULTS: The nested-ASP-PCR method was successfully established to test the resistance mutation points 2142, 2143 and 2144 of the 23 SrR NA gene of H. pylori. Among 30 samples of gastric tissue and saliva, the H. pylori detection rate of nested-ASP-PCR was 90% and 83.33%, while the detection rate of ASP-PCR was just 63% and 56.67%. Especially in the saliva samples, nested-ASP-PCR showed much higher sensitivity in H. pylori detection and resistance mutation rates thanASP-PCR. In the 99 RUT-positive gastric tissue and saliva samples, the H. pylori-positive detection rate by nested-ASP-PCR was 87(87.88%) and 67(67.68%), in which there were 30 wild-type and 57 mutated strains in gastric tissue and 22 wild-type and 45 mutated strains in saliva. Genotype analysis showed that three-points mixed mutations were quite common, but different resistant strains were present in gastric mucosa and saliva. Compared to the high sensitivity shown by nested-ASP-PCR, the positive detection of bacterial culture with gastric tissue samples was 50 cases, in which only 26 drug-resistant strains were found through analyzing minimum inhibitory zone of clarithromycin. CONCLUSION: The nested-ASP-PCR assay showed higher detection sensitivity than ASP-PCR and drug sensitivity testing, which could be performed to evaluate clarithromycin resistance of H. pylori.