HUITAI rapid urease test: a new ultra-rapid biopsy urease test for the diagnosis of Helicobacter pylori infection.
ABSTRACT The gastric biopsy urease test is an accurate and robust diagnostic test for Helicobacter pylori infection. Large endoscopy units use their own homemade unbuffered ultra-rapid urease test for diagnosis of H. pylori infection but several commercial rapid urease tests are available.
To compare the accuracy and reaction time of a new biopsy urease test, HUITAI rapid urease test, in the diagnosis of H. pylori infection.
Consecutive patients presenting with dyspepsia to the endoscopy unit, University of Malaya Medical Center were recruited for the study. Patients who were previously treated for H. pylori infection or who had received antibiotics, proton pump inhibitors or bismuth compounds in the preceding 4 weeks were excluded. The H. pylori diagnosis was made based on the homemade rapid urease test, histology and culture of gastric biopsies. Biopsies from the antrum and corpus of the stomach were taken for this purpose. In addition, two antral and corpus biopsies were taken for the HUITAI rapid urease test. A positive diagnosis of H. pylori infection was made when the culture was positive or if both histology and the rapid urease test were positive. A negative diagnosis was made when all tests were negative. The positive reaction time of the HUITAI rapid urease test was carefully timed up to 60 min.
Two hundred and six patients were recruited in the study. One hundred and twelve were diagnosed as having an H. pylori infection while the other 94 patients were regarded as negative. There were no spoiled tests and no indeterminate results. The sensitivity of the HUITAI rapid urease test was 98.2% (95% confidence interval (CI): 93.7%, 99.8%), specificity, 99.0% (95% CI: 94.2%, 100%), positive predictive value, 99.0% (95% CI: 95.1%, 100%), negative predictive value, 97.9% (95% CI: 92.6%, 99.7%). The overall diagnostic accuracy for the HUITAI rapid urease test was 98.5% (95% CI: 96.6, 99.9). The median positive reaction time was 1.0 min (25-75% inter-quartile range [IQR]: 1.0-3.0 min).
The HUITAI rapid urease test is highly accurate for the diagnosis of an H. pylori infection and showed a very rapid positive reaction time.
- The Lancet 04/1988; 1(8587):704. · 39.06 Impact Factor
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ABSTRACT: Rapid urease testing is the initial endoscopic test of choice for the diagnosis of Helicobacter pylori. Determination of the relative diagnostic yields and times to a positive test for the different rapid urease tests is important for endoscopists. We compared three commercially available tests using histologic examination and culture as a gold standard. Patients undergoing upper endoscopy had six biopsy specimens taken from the antrum and six from the body with a large-channel biopsy forceps. Each set of six specimens was divided as follows: one each for CLOtest, Hpfast, and Pyloritek rapid urease tests; one for culture; and two for histologic examination (H&E, Genta). All tests were read every 15 minutes for 1 hour; the final reading for Pyloritek was at 1 hour. CLOtest and Hpfast were also read at 4 hours and 24 hours. One hundred seventy-three sets of biopsy specimens from 87 patients were evaluated; 98 (57%) of the 173 sets were positive for H. pylori by histologic examination and/or culture. The mean and median times to a positive test were significantly less for Pyloritek (0.5 +/- 0.02 hour and 0.5 hour) than for CLOtest (2.0 +/- 0.6 hour and 0.75 hour) or Hpfast (2.2 +/- 0.6 hour and 0.5 hour). The sensitivities at the final readings were similar among the three tests (CLOtest: 93%; Hpfast: 88%; Pyloritek: 89%), but sensitivities at 1 hour were significantly better for Pyloritek (89%) than for CLOtest (71%) or Hpfast (66%). At 4 hours, sensitivities for CLOtest and Hpfast improved significantly and were not significantly different from those of Pyloritek. Specificities were 99% to 100% at all times for all three tests. The three rapid urease tests, CLOtest, Hpfast, and Pyloritek, provide comparable results, with sensitivities around 90% and specificities around 100%. The Pyloritek becomes positive more rapidly than the CLOtest or Hpfast. If a reading is desired within 1 hour, the Pyloritek provides a greater sensitivity than the CLOtest or Hpfast without any sacrifice in specificity.Gastrointestinal Endoscopy 11/1996; 44(5):523-6. · 5.21 Impact Factor
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ABSTRACT: Campylobacter pyloridis colonization of the stomach may be an etiological factor in gastritis and peptic ulceration. Campylobacter pyloridis produces large amounts of urease, and the presence of this enzyme in gastric mucosa usually indicates infection with the organism. In this paper we describe the use of a rapid urease test (CLOtest) to detect C. pyloridis infection in gastric mucosal biopsies. In 141 consecutive endoscopy cases, antral biopsies were taken for culture and histology, and an extra biopsy was inserted into the CLOtest gel. There were 79 patients infected with C. pyloridis, 78 of whom were detected by CLOtest: 75% were positive at 20 min, 92% at 3 h, and 98% at 24 h. There were no false positive results. Eighteen infected patients were rebiopsied after a course of amoxycillin and bismuth subcitrate. Active chronic gastritis resolved in eight of nine who were cleared of the organism, but histological gastritis was unchanged in nine patients who were still infected. CLOtest is a simple, sensitive, and highly specific test that enables the endoscopist to diagnose C. pyloridis infection in the endoscopy room. A negative test after antibiotic therapy correlates with clearance of the bacteria and healing of active gastritis.The American Journal of Gastroenterology 04/1987; 82(3):200-10. · 7.55 Impact Factor