Evaluation of Immunological Rapid Urease Testing for Detection of Helicobacter pylori

Satô, Tadashi; Fujino, Masayuki; Kojima, Yuichiro; Kitahara, Fumiaki; Morozumi, Atsuro; Nagata, Kumiko; Nakamura, Michihiro; Hosaka, Hiroko

doi:10.1007/s100960000282

Cited by 15 publications

(21 citation statements)

References 6 publications

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“…Important features favoring survival of the organism in an acidic environment are its shape and motility, reduced oxygen requirement, strong adhesion to gastric cells, and urease production. Urease converts urea into ammonium and bicarbonate, neutralizing gastric acid and providing protection against the aggressive environment of the stomach lumen until the organism can reach the submucosal layer with its neutral pH value [20,21]. Non-invasive methods that could monitor infection would help in rapid identification of this dangerous bacterium.…”

Section: Introductionmentioning

confidence: 99%

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Rapid identification of Escherichia coli and Helicobacter pylori in biological samples by capillary zone electrophoresis

Kłodzińska

Dahm

Różycki

et al. 2006

J of Separation Science

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The differences in surface charge of different bacteria can be exploited for their separation by capillary electrophoresis. However, this method of separation of microorganisms is beset with various drawbacks such as adhesion of bacteria to the fused silica surface or cluster formation. To overcome these phenomena we investigated the addition of poly(ethylene oxide) as a focusing agent to the running buffer and used calcium and myoinositol hexakisphosphate as specific ions that interact with the bacterial surface, changing its electrical properties and electrophoretic mobilities. In the present work, we applied CZE to identification of E. coli in infected urine (direct injection) from patients with urinary tract infections and to identification of Helicobacter pylori, which is a gram-negative bacillus responsible for one of the most common infections found in humans worldwide. Helicobacter pylori colonize the stomach and are responsible for severe diseases of the gastric tract, ranging from chronic gastric ulcer to gastric cancer.

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Section: Introductionmentioning

confidence: 99%

“…The main problem is that our digestive tract can be colonized by five different strains of H. pylori. Rapid separation of these different strains would be very useful in real-life diagnosis of disease and an important step on the way to eradication of this bacterium [20,21].…”

Section: Introductionmentioning

confidence: 99%

Rapid identification of Escherichia coli and Helicobacter pylori in biological samples by capillary zone electrophoresis

Kłodzińska

Dahm

Różycki

et al. 2006

J of Separation Science

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“…After pharyngeal anaesthesia with 1 % lidocaine hydrochloride, a disinfected endoscope was inserted into the stomach and gastric juice was collected through the aspiration channel of the endoscope. The status of H. pylori infection was determined from the results of culture and an immunological rapid urease test described previously (Sato et al, 2000). A patient was considered to be H. pylori-positive if the culture was positive.…”

Section: Methodsmentioning

confidence: 99%

l-Serine, d- and l-proline and alanine as respiratory substrates of Helicobacter pylori: correlation between in vitro and in vivo amino acid levels

Nagata

Satô

et al. 2003

Microbiology

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Helicobacter pylori whole cells showed high rates of oxygen uptake with L-serine and L-proline as respiratory substrates, and somewhat lower rates with D-alanine and D-proline. These respiratory activities were inhibited by rotenone and antimycin A at low concentrations. Since pyruvate was produced from L-serine and D-and L-alanine in whole cells, the respiratory activities with these amino acids as substrates occurred via pyruvate. Whole cells showed 2,6-dichlorophenolindophenol (DCIP)-reducing activities with D-and L-proline and D-alanine as substrates, suggesting that hydrogen removed from these amino acids also participated in oxygen uptake by the whole cells. High amounts of L-proline, D-and L-alanine, and L-serine were present in H. pylori cells, and these amino acids also predominated in samples of human gastric juice. H. pylori seems to utilize D-and L-proline, D-alanine and L-serine as important energy sources in its habitat of the mucous layer of the stomach. INTRODUCTIONHelicobacter pylori is a Gram-negative bacterium associated with gastric inflammation and peptic ulcer disease and is a risk factor for gastric cancer (Blaser, 1990;Parsonnet et al., 1991Parsonnet et al., , 1994Rabeneck & Ransohoff, 1991). The natural habitat of H. pylori is the mucous layer of the human gastric epithelium, where populations are considered to persist for the lifetime of the host. H. pylori is a microaerophilic bacterium exhibiting a strict respiratory form of metabolism and oxidizing organic acids as an energy source. The carbohydrate utilized by H. pylori as the energy source has been reported to be only glucose . More recently the whole-genome analysis of H. pylori has supported these findings (Tomb et al., 1997). However, the incorporation of glucose from the culture medium was not influenced by inhibitors known to affect other bacterial glucose-related enzymes, such as glucose permease, and the K m value of its glucose transport was reported to be rather high, 4?8 mM (Burns & Mendz, 2001). In addition, glucose added to the culture medium composed of a mixture of amino acids was not utilized until the amino acids were significantly depleted Mendz & Hazell, 1995). These results suggested that glucose is not a preferred energy substrate of H. pylori. Candidates for the substrates of energy metabolism in this organism are thought to be organic acids such as pyruvate, D-lactate and succinate. Chang et al. (1995) reported that lower concentrations (25 mM) of pyruvate, D-lactate and succinate were rapidly oxidized, and the respiration rates were relatively high, suggesting that H. pylori cells may have adapted to utilizing these substrates in vivo. However, the oxygen uptake during lactate and pyruvate oxidation was insufficient for their complete oxidation to CO 2 and H 2 O via the citric acid cycle (Chang et al., 1995;Kelly et al., 2001). Thus, instead of organic acids, amino acids are considered to be other potential respiratory substrates and energy sources in H. pylori cells.Little study has been done on amino acids...

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“…More recently, Sato et al have developed the immunological RUT (IRUT) for detection of H. pylori infection, providing satisfactory diagnostic efficacy [19]. In this system, each gastric mucus sample, which is collected by broad gastric brushing under endoscopic guidance, is incubated with a solid-phase tip coated with anti-H. pylori urease antibody.…”

Section: Introductionmentioning

confidence: 99%

“…In this system, each gastric mucus sample, which is collected by broad gastric brushing under endoscopic guidance, is incubated with a solid-phase tip coated with anti-H. pylori urease antibody. The tip is reacted with a urea substrate solution and the resultant pH change inside is measured [19]. Collectively, it is rational to apply the IRUT without the need for biopsies for assessment of H. pylori infection in cases presenting a risk for bleeding complications.…”

Section: Introductionmentioning

confidence: 99%

Usefulness of the Immunological Rapid Urease Test for Detection of Helicobacter pylori in Patients Who are Reluctant to Undergo Endoscopic Biopsies

et al. 2006

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Cardiovascular diseases and liver cirrhosis are in the list of Helicobacter pylori-related extragastric diseases. Patients with cirrhosis and cardiovascular diseases under the control of aspirin have increased risk of gastrointestinal bleeding. The immunological rapid urease test (IRUT) provides a rapid and safe diagnostic test for H. pylori using gastric mucus collected at endoscopy. We investigated its usefulness in 93 patients with these extragastric diseases including 46 with H. pylori infection assessed by urea breath test and serology. Twenty H. pylori-infected patients received eradication therapy and the IRUT was assessed to evaluate the efficacy of bacterial eradication. The sensitivity, specificity, and positive and negative predictive values for IRUT were 96%, 90%, 90%, and 96%, respectively. The results of IRUT completely agreed with those of urea breath test following anti-H. pylori therapy. The IRUT has acceptable diagnostic performance in such cohorts reluctant to undergo endoscopic biopsies due to the risk of bleeding.

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Evaluation of Immunological Rapid Urease Testing for Detection of Helicobacter pylori

Cited by 15 publications

References 6 publications

Rapid identification of Escherichia coli and Helicobacter pylori in biological samples by capillary zone electrophoresis

Rapid identification of Escherichia coli and Helicobacter pylori in biological samples by capillary zone electrophoresis

l-Serine, d- and l-proline and alanine as respiratory substrates of Helicobacter pylori: correlation between in vitro and in vivo amino acid levels

Usefulness of the Immunological Rapid Urease Test for Detection of Helicobacter pylori in Patients Who are Reluctant to Undergo Endoscopic Biopsies

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