The Experts below are selected from a list of 3270 Experts worldwide ranked by ideXlab platform
David Y. Graham - One of the best experts on this subject based on the ideXlab platform.
-
urea breath Test and Rapid Urease Test
2016Co-Authors: Akiko Shiotani, Maria Pina Dore, David Y. GrahamAbstract:The urea breath Test (UBT) and the Rapid Urease Test (RUT) are the most commonly used diagnostic methods for H. pylori infection and rely on detecting the presence of Urease produced by H. pylori. The sensitivity of the UBT is excellent (often exceeding 95 %). The majority of false-positive results after eradication occur when the results are near the cutoff value and are most frequent in areas where atrophic gastritis is common and citric acid is not used as an adjuvant. The sensitivity of RUT is slightly less (approximately 80–95 %). Increasing the number and size of biopsy fragments, collecting them from the antrum and corpus, or sampling gastric mucus more widely instead of biopsy samples achieves better results with the RUT. Negative results of the either Test should not be taken as evidence of the absence of the infection especially in PPI users as well as in patients with bleeding or a history of partial gastrectomy.
-
diagnosis of helicobacter pylori using the Rapid Urease Test
2015Co-Authors: Takahiro Uotani, David Y. GrahamAbstract:Helicobacter pylori (H. pylori) is a major human pathogen which causes progressive gastroduodenal damage. Guidelines recommend that, unless there are compelling reasons to delay, treatment is indicated for all patients in whom the infection is diagnosed. The Rapid Urease Test (RUT) is a popular diagnostic Test in that it is a Rapid, cheap and simple Test that detects the presence of Urease in or on the gastric mucosa. The sensitivity and specificity are generally high and many versions have been approved for use in humans. Best results are obtained if biopsies are obtained from both the antrum and corpus. The tissue sample embedded in the RUT gel can also be utilized for other Tests such as for molecular based Tests of microbial susceptibility or for host factors. False-positive results are rare if the RUT contains an antibacterial agent to prevent growth of Urease-containing contaminants and the Tests are discarded at 24 hours. The use of antimicrobial drugs and proton pump inhibitors as well as the presence of inTestinal metaplasia may result in false-negative results. A negative Test should not be used as the criteria for cure or in cases where accuracy is important for patient management such as in upper gastroinTestinal bleeding. Interpretation of the Test should take into account the preTest probability and the prevalence of H. pylori in the population. The Test can also be used to provide an informal assessment of the accuracy of the histopathology result and discrepancies should prompt a review of the histopathology and discussions with the pathologist.
-
the best gastric site for obtaining a positive Rapid Urease Test
1996Co-Authors: Jae Soon Woo, David Y. Graham, M M Yousfi, Hala M T Elzimaity, Robert M GentaAbstract:BackgroundRapid Urease Tests (RUTs) provide a simple, sensitive method of detecting Helicobacter pylori infection. Objectives.Our aim, therefore, was to determine whether the yield of detecting H. pylori infection by RUT varied depending on the site of gastric biopsy. Materials and Methods.Gastric biopsies were obtained from 50 patients for RUT by use of hpfast (GI Supply, Camp Hill, PA). Biopsies were taken from the prepyloric greater curve antrum, from the gastric angle, and from the greater curve in mid-corpus. One biopsy specimen was placed in the RUT gel, and the biopsy from the adjacent mucosa was placed in formalin for subsequent histological evaluation by using the Genta stain. RUTs were examined and scored at intervals of 5, 10, 15, 30, and 45 minutes and after 1, 2, 4, and 24 hours. Results.Fifty patients were entered in the Test (150 RUTs), 32 having H. pylori infection. There were no false-positive RUTs (specificity, 100%). The gastric angle site was positive in 100%. The prepyloric site was positive in 87%, and the corpus site was positive in 84.4% (p < .052 for angle or prepyloric antrum versus corpus). The most common pattern was for all to be positive (74%). The median time to positivity was similar with angle and prepyloric sites (37.5 and 60 minutes, respectively, p= not significant) and shorter than the corpus biopsy (180 minutes); (p < .05 for angle or prepyloric antrum versus corpus). Conclusion.The maximum probability for detecting H. pylori infection using a RUT is to obtain a biopsy from the gastric angle. To prevent missing a positive result when inTestinal metaplasia is present, we recommend that (at a minimum) biopsies be taken from both the angle and the corpus.
-
evaluation of a new reagent strip Rapid Urease Test for detection of helicobacter pylori infection
1996Co-Authors: M M Yousfi, Hala M T Elzimaity, Robert M Genta, David Y. GrahamAbstract:Abstract Background: Rapid Urease Tests are commonly used as a convenient method to detect Helicobacter pylori infection. Our previous experiments demonstrated enhanced efficacy of agar gel Rapid Urease Test compared with reagent strip Rapid Urease Tests. We evaluated the efficacy of PyloriTek, a new reagent strip Rapid Test for detecting H. pylori infection. Methods: Gastric antral mucosal biopsy specimens were obtained for comparison between agar gel Rapid Urease Tests and PyloriTek (200 specimens). The Rapid Urease Test to be used first was selected randomly. H. pylori status was determined using the Genta stain. Culture was performed to confirm H. pylori status when false Rapid Urease Tests were suspected. Results: One hundred patients were studied; 68 had H. pylori infection. There were two false-negative and one false-positive PyloriTek when scored at 1 hour, compared with only one false-positive and no false-negative Tests at 2 hours. With the agar gel Rapid Urease Tests, there were no false-positive Tests and 5 false-negative Tests when scored at 1 hour, 2 false-negative Tests at 12 hours and 1 at 24 hours; there were no false-positive Tests. At 1 hour, 3% (95% CI=1% to 9%) of PyloriTek Tests had an erroneous categorization of H. pylori status compared with 5% for the agar gel Rapid Urease Tests (95% CI=1.6% to 11%) ( p > 0.7). Conclusion: The new reagent strip Rapid Urease Test, PyloriTek, is Rapid and comparable in accuracy to agar gel Rapid Urease Tests for detecting H. pylori infection. (GastroinTest Endosc 1996;44:519-22.)
-
confirmation of successful therapy of helicobacter pylori infection number and site of biopsies or a Rapid Urease Test
1995Co-Authors: Hala M T Elzimaity, Robert M Genta, M T Alassi, David Y. GrahamAbstract:Background : Although a number of Tests have been described to detect the presence of Helicobacter pylori in biopsy specimens, studies of positive and negative value have largely been performed on untreated patients ; Testing the reliability of posttherapy has not been done. Methods : We examined the value of the number and site of biopsies performed and the method used for specimen evaluation posttherapy. For postantimicrobial therapy of 141 patients with previously confirmed H. pylori infection, three biopsies were taken, two from the antrum and one from the corpus. Individual slides were coded, randomized, and interpreted blindly by two pathologists. Furthermore, in 143 patients, a biopsy specimen was taken from the antrum and was immediately inserted into the gel of the Rapid Urease Test, and the results were compared with those obtained from histopathology obtained at the same time. Results : In 71 patients, H. pylori therapy was unsuccessful ; in 61 (86%), all three sites were positive. The highest yield with a single large cup biopsy specimen was 94% ; the lowest was 91%. Two antral biopsies were negative in 4% [95% confidence interval (CI) = 1-12%]. The combination of a biopsy from the angulus incisura and one from the greater curvature of the corpus correctly identified all treatment failures (95% CI = 95-100 %). The Rapid Urease Test was false-negative in 5% (95% CI = 1-13%) ; there were no false-positives. Conclusion : Use of either the Rapid Urease Test or two antral biopsies for evaluation of success of antimicrobial therapy for H. pylori infection will result in a false declaration of cure in at least 5% of cases. Three large cup gastric mucosal biopsies for histology are recommended for evaluation of the success of anti-H. pylori therapy.
Jin Il Kim - One of the best experts on this subject based on the ideXlab platform.
-
dual priming oligonucleotide based multiplex pcr using tissue samples from the Rapid Urease Test kit for the detection of helicobacter pylori in bleeding peptic ulcers
2016Co-Authors: Woo Chul Chung, Tae Ho Kim, Dae Young Cheung, Byungwook Kim, Sung Soo Kim, Eun Jung Jeon, Jae Myung Park, Jin Il KimAbstract:Abstract Background In patients with peptic ulcer bleeding (PUB), diagnostic Tests for Helicobacter pylori (H. pylori) infection have low sensitivity. The aim of our study was to investigate the diagnostic yield of dual-priming oligonucleotide-based multiplex (DPO)-PCR using tissue samples from the Rapid Urease Test (RUT, CLO®Test) kit in patients with PUB. Methods We prospectively enrolled patients with PUB. During second-look endoscopy, gastric biopsy specimens for histology and RUT were obtained from a total of 170 patients. DPO-PCR Tests were performed on tissue samples obtained from the CLO®Test kit. If Testing for H. pylori was negative, endoscopy with re-biopsy was performed 8 weeks after the bleeding episode. Results H. pylori-associated bleeding was confirmed in 64.1% (109/170) of the patients. At the bleeding episode, the diagnostic sensitivities of RUT, histology, and DPO-PCR Test were 47.7% (52/109), 71.6% (78/109) and 97.2% (106/109), respectively (p Conclusions In patients with PUB, the DPO-PCR Test could be a useful diagnostic tool for H. pylori infection. Particularly given a negative RUT result, subsequent DPO-PCR Testing of tissue samples from the CLO®Test kit could be of considerable benefit.
-
dual priming oligonucleotide based multiplex pcr using tissue samples in Rapid Urease Test in the detection of helicobacter pylori infection
2014Co-Authors: Woo Chul Chung, Sung Hoon Jung, Tae Ho Kim, Dae Young Cheung, Byungwook Kim, Sung Soo Kim, Jin Il Kim, Eun Young SinAbstract:AIM: To investigate whether tissue samples processed by the Rapid Urease Test (RUT) kit are suitable for dual-priming oligonucleotide-based multiplex polymerase chain reaction (DPO-PCR) to detect Helicobacter pylori (H. pylori). METHODS: A total of 54 patients with specific gastroinTestinal symptom were enrolled in this study. During endoscopy, gastric biopsy specimens were taken for histology, RUT, and DPO-PCR. DPO-PCR was performed on gastric biopsy samples and tissue samples that were analyzed by RUT at 2 separate institutes. In detecting H. pylori, the concordance rate of the DPO-PCR Tests between the tissue samples that had been submitted to RUT and the gastric biopsy samples was investigated. RESULTS: H. pylori co-occurred with 76.0% (19/25) of gastric ulcers, 64.3% (9/14) of duodenal ulcers, and 33.3% (4/12) of gastritis cases. H. pylori infection was found in 100% (3/3) of the patients with both gastric and duodenal ulcers. Overall, H. pylori was detected in 35 of 54 (64.8%) patients. The diagnostic sensitivities of histology, RUT, and DPO-PCR were 85.7% (30/35), 74.3% (26/35), and 97.1% (34/35), respectively (P = 0.02). The positive predictive value (PPV) of DPO-PCR was 94.4%, whereas the negative predictive value (NPV) was 94.7%. In the Rapid Urease Test (CLOTest)-negative cases, the frequency of positive DPO-PCR and histologic results was 20.0% (7/35). The concordance rate of the DPO-PCR Tests between the tissue samples from the RUT kit and the gastric biopsy samples was 94.4% (51/54). The rate of DPO-PCR and silver stain positivity in the RUT-negative cases was 20.0% (7/35). CONCLUSION: In diagnosing H. pylori infection, DPO-PCR can be performed on tissue samples that have been processed by the RUT kit. Particularly, in patients with RUT-negative results, DPO-PCR on these tissue samples could be helpful in detecting of H. pylori infection.
John Wong - One of the best experts on this subject based on the ideXlab platform.
-
a prospective comparison of locally made Rapid Urease Test and histology for the diagnosis of helicobacter pylori infection
1997Co-Authors: Kentman Chu, Ronnie T P Poon, Henry H Tuen, Simon Law, F J Branicki, John WongAbstract:Abstract Background : A number of noncommercial preparations of Urease Test have been described. The present prospective study evaluated the accuracy of one such preparation for the diagnosis of Helicobacter pylori infection. Methods : From February 1996 to November 1996, all patients undergoing elective upper endoscopy in a single endoscopy facility were included. Three antral biopsy specimens were taken. Two specimens were subjected to histologic examination, and one specimen was placed into a “locally made Rapid Urease Test” (LRUT). Results of histologic examinations were taken as standards for comparison. The final result of LRUT was obtained on scrutiny of color changes at 4 hours after the start of the Test. Results : Two thousand three hundred sixteen patients (male/female = 1.5:1) with a mean age of 56.7 ± 0.4 years were included. Five hundred sixty-two patients (24.3%) had a history of eradication treatment for H. pylori . Nine hundred fifty-three patients (41.1%) were found to be positive for H. pylori on histologic examination. In patients in whom a history of eradication therapy was absent, the sensitivity, specificity, and positive and negative predictive values of the LRUT were 92.8%, 97.6%, 97.5%, and 93.0%, respectively. In patients with a history of eradication treatment, the corresponding figures were 76.1%, 99.6%, 96.2%, and 96.9%. Conclusions : The locally made Rapid Urease Test provides a simple, safe, Rapid, inexpensive, and accurate Test for the diagnosis of H. pylori infection. (GastroinTest Endosc 1997;46:503-6.)
Woo Chul Chung - One of the best experts on this subject based on the ideXlab platform.
-
dual priming oligonucleotide based multiplex pcr using tissue samples from the Rapid Urease Test kit for the detection of helicobacter pylori in bleeding peptic ulcers
2016Co-Authors: Woo Chul Chung, Tae Ho Kim, Dae Young Cheung, Byungwook Kim, Sung Soo Kim, Eun Jung Jeon, Jae Myung Park, Jin Il KimAbstract:Abstract Background In patients with peptic ulcer bleeding (PUB), diagnostic Tests for Helicobacter pylori (H. pylori) infection have low sensitivity. The aim of our study was to investigate the diagnostic yield of dual-priming oligonucleotide-based multiplex (DPO)-PCR using tissue samples from the Rapid Urease Test (RUT, CLO®Test) kit in patients with PUB. Methods We prospectively enrolled patients with PUB. During second-look endoscopy, gastric biopsy specimens for histology and RUT were obtained from a total of 170 patients. DPO-PCR Tests were performed on tissue samples obtained from the CLO®Test kit. If Testing for H. pylori was negative, endoscopy with re-biopsy was performed 8 weeks after the bleeding episode. Results H. pylori-associated bleeding was confirmed in 64.1% (109/170) of the patients. At the bleeding episode, the diagnostic sensitivities of RUT, histology, and DPO-PCR Test were 47.7% (52/109), 71.6% (78/109) and 97.2% (106/109), respectively (p Conclusions In patients with PUB, the DPO-PCR Test could be a useful diagnostic tool for H. pylori infection. Particularly given a negative RUT result, subsequent DPO-PCR Testing of tissue samples from the CLO®Test kit could be of considerable benefit.
-
dual priming oligonucleotide based multiplex pcr using tissue samples in Rapid Urease Test in the detection of helicobacter pylori infection
2014Co-Authors: Woo Chul Chung, Sung Hoon Jung, Tae Ho Kim, Dae Young Cheung, Byungwook Kim, Sung Soo Kim, Jin Il Kim, Eun Young SinAbstract:AIM: To investigate whether tissue samples processed by the Rapid Urease Test (RUT) kit are suitable for dual-priming oligonucleotide-based multiplex polymerase chain reaction (DPO-PCR) to detect Helicobacter pylori (H. pylori). METHODS: A total of 54 patients with specific gastroinTestinal symptom were enrolled in this study. During endoscopy, gastric biopsy specimens were taken for histology, RUT, and DPO-PCR. DPO-PCR was performed on gastric biopsy samples and tissue samples that were analyzed by RUT at 2 separate institutes. In detecting H. pylori, the concordance rate of the DPO-PCR Tests between the tissue samples that had been submitted to RUT and the gastric biopsy samples was investigated. RESULTS: H. pylori co-occurred with 76.0% (19/25) of gastric ulcers, 64.3% (9/14) of duodenal ulcers, and 33.3% (4/12) of gastritis cases. H. pylori infection was found in 100% (3/3) of the patients with both gastric and duodenal ulcers. Overall, H. pylori was detected in 35 of 54 (64.8%) patients. The diagnostic sensitivities of histology, RUT, and DPO-PCR were 85.7% (30/35), 74.3% (26/35), and 97.1% (34/35), respectively (P = 0.02). The positive predictive value (PPV) of DPO-PCR was 94.4%, whereas the negative predictive value (NPV) was 94.7%. In the Rapid Urease Test (CLOTest)-negative cases, the frequency of positive DPO-PCR and histologic results was 20.0% (7/35). The concordance rate of the DPO-PCR Tests between the tissue samples from the RUT kit and the gastric biopsy samples was 94.4% (51/54). The rate of DPO-PCR and silver stain positivity in the RUT-negative cases was 20.0% (7/35). CONCLUSION: In diagnosing H. pylori infection, DPO-PCR can be performed on tissue samples that have been processed by the RUT kit. Particularly, in patients with RUT-negative results, DPO-PCR on these tissue samples could be helpful in detecting of H. pylori infection.
Jeong Yoon Yim - One of the best experts on this subject based on the ideXlab platform.
-
prospective evaluation of a new stool antigen Test for the detection of helicobacter pylori in comparison with histology Rapid Urease Test 13c urea breath Test and serology
2011Co-Authors: Jeongmin Choi, Chung Hyeon Kim, Donghee Kim, Su Jin Chung, Ji Hyun Song, Jung Mook Kang, Jong In Yang, Min Jung Park, Young Sun Kim, Jeong Yoon YimAbstract:Background and Aims: This study aimed to evaluate the efficacy of a new polyclonal enzyme immunoassay for the detection of Helicobacter pylori (H. pylori) antigen in stool by determination of the optimal cut-off value in the screening population. Methods: A consecutive 515 patients undergoing a routine health check-up were prospectively enrolled. H. pylori infection was defined if at least two of four Tests (histology, Rapid Urease Test, 13C-urea breath Test, and serology) were positive. A stool antigen Test (EZ-STEP H. pylori) was performed for the detection of H. pylori. The optimal cut-off value was determined by the receiver–operator characteristic curve. The diagnostic performance of each Test was evaluated with regard to the histological diagnosis of atrophic gastritis (AG)/inTestinal metaplasia (IM), degree of AG/IM, and old age. Results: Sensitivity, specificity, positive and negative predictive values, and accuracy of the stool antigen Test were 93.1%, 94.6%, 95.1%, 92.3%, and 93.8%, respectively. The sensitivity of histology, Rapid Urease Test, and the 13C-urea breath Test ranged from 89.1% to 97.6%, and their specificity was > 98%, while serology had high sensitivity, but low specificity. The accuracy of the stool antigen Test was comparable to that of other methods (93.6–95.9%), whereas it was higher than that of serology. The stool antigen Test still showed good diagnostic performance in the setting of progression of AG/IM and in patients over 40 years. Conclusions: The performance of a new stool antigen Test was comparable to that of other methods in the diagnosis of H. pylori infection for the screening population, even with the presence of AG/IM.