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The accutest h. Pylori urease test is a qualitative detection method for helicobacter pylori in gastric mucosal biopsy specimens from symptomatic adult patients. The intended use, biological principle, and procedure for using the test to diagnose h. Pylori infections. The test is based on the bacterium's production of urease, which allows it to tolerate low ph and utilize urea as a nitrogen source.
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Facilities performing testing must have a CLIA Certificate of Waiver. 42 USA 263a(c)(2). Any laboratory eligible for a Certificate of Waiver must follow the test system instructions, including use with only the waived specimen type, instructions for limitations/intended use, and performance of QC testing as a failure-alert mechanism. (42 CFR 493.15(e).) Any modification to the test or the manufacturer’s instructions will result in the test being classified as highly complex.
Treat all biopsy specimens as if capable of transmitting disease. Caution should be used in handling and disposing of these specimens at bio-safety level 2 as recommended in the Centers for Disease Control/National Institute of Health Manual, Bio-safety in Microbiological and Biomedical Laboratories, 1984. Your laboratory safety procedures should also be followed as well as any other local or state health recommendations. INTENDED USE: Accutest H. pylori Urease Test is intended for the qualitative detection of the urease enzyme in gastric mucosal biopsy specimens for the presumptive determination of Helicobacter pylori in symptomatic adult patients. SUMMARY / BIOLOGICAL PRINCIPLE: Helicobacter pylori has been shown to cause active chronic gastritis and has been implicated as a primary etiologic factor in duodenal ulcer disease, gastric ulcer and non ulcer dyspepsia^1. By causing chronic inflammation Helicobacter pylori may weaken the mucosal defenses and allow acid and pepsin to disrupt the epithelium. H.pylori produces large amounts of urease enzyme^2. Although urease primarily allows H. pylori to utilize urea as a nitrogen source, the breakdown of urea also produces high local concentrations of ammonia, which enable the organism to tolerate low pH (see reaction below).
urease (NH 2 )CO + 2H 2 0 + H +^ ------> 2NH 4 +^ + HCO 3 - urea ammonium bicarbonate ion ion
Although H.pylori can be detected with histology or culture of gastric tissue, simple tests for the presence of urease enable more rapid and convenient diagnosis. Tests for gastric urease are specific for H.pylori because mammalian cells do not produce urease and very few micro-organisms survive in the stomach, except for H. pylori. WARNING: POTENTIAL BIOHAZARDOUS MATERIAL Note: for in vitro diagnostic use only. Treat all biopsy specimens as if capable of transmitting disease. Caution should be used in handling and disposing of these specimens at bio-safety level 2 as recommended in the Centers for Disease Control/National Institute of Health Manual, Bio-safety in Microbiological and Biomedical Laboratories, 1984. Your laboratory safety procedures should also be followed as well as any other local or state health recommendations. STORAGE : Accutest H. pylori Urease Test should be stored at room temperature away from direct light. Accutest H. pylori Urease Test has a shelf life of 24 months. Before use, each Accutest H. pylori Urease Test slide should be inspected to make sure the test surface is yellow. If the test surface is red or magenta the slide should not be used. SPECIMEN COLLECTION AND HANDLING Preparation of the patient: Patients should not have taken antibiotics or bismuth salts for at least three weeks prior to endoscopy. Suppression of H. pylori by these agents makes the organism difficult to detect by any means, and re-growth of H. pylori may be patchy, leading to false negative results in the first few weeks after treatment. Taking and Inserting the Biopsy:
RESULTS: Reading the Accutest H. pylori Urease Test:
MATERIALS PROVIDED: Accutest H. pylori Urease Test is packaged in boxes of 50 test slides with an instruction sheet.
MATERIALS REQUIRED BUT NOT INCLUDED WITH THE TEST: Not supplied with the Accutest H. pylori Urease tests are the biopsy forceps for collecting the specimens or the blunt instrument for transferring the specimen to the test.
QUALITY CONTROL: We recommend a positive external control must be preformed when opening a new test kit. The test kit size must not exceed 50. Accutest H. pylori Urease Test controls come in two forms: Dry Paper Dot Control and Liquid Control. Either may be used. If the Accutest H. pylori Urease Test is negative after 1 hour and there is a question if the test has functioned properly, perform the following positive control test:
LIMITATIONS: False negative Accutest H. pylori Urease Test results may occur when very low numbers of H. pylori are present or the bacterium has a patchy distribution. For example, in 1-5% of patients the bacterium is present in the body of the stomach but not in the antrum, or vice versa. In patients with widespread intestinal metaplasia, an area of intestinal epithelium may be biopsied. As H. pylori does not colonize intestinal mucosa, a false negative Accutest H. pylori Urease Test can result. To reduce the occurrence of false negatives, two Accutest H. pylori Urease tests should be performed, one with a sample from the antrum and one from the body of the stomach. All tests for H.pylori, including Accutest H. pylori Urease Test, will be less sensitive if the patient has recently taken antibiotics or bismuth. Re-growth of H.pylori may be patchy after suppression with antibiotic. Again, an extra biopsy may be taken for Accutest H. pylori Urease Test to avoid a false negative reading. False positive Accutest H. pylori Urease Test results are rare. Theoretically, false positive Accutest H. pylori Urease Test results could occur in patients who have achlorhydria (for example patients with pernicious anemia, previous gastric surgery, or who have recently taken antacid or large doses of H2 receptor antagonists). When acid is absent, commensal organisms such as Proteus spp. may grow in the stomach and produce urease. False
Product Insert
positive reactions due to bacteria other than H. pylori will not usually react before 3 hours because these bacteria produce much less urease than H. pylori. If there are factors which might adversely affect the performance of Accutest H. pylori Urease Test, the physician is advised to consider other diagnostic measures, such as culture with Gram stain and/or histology, in order to confirm or disprove a diagnosis of H. pylori infection.
USERS WITH COLOR BLINDNESS Users with color blindness should seek assistance in interpreting the results of this test. PERFORMANCE CHARACTERISTICS During a clinical study conducted in 2006 comparing samples of Accutest H. pylori Urease Test with histology, Accutest H. pylori Urease Test was shown to be 100% specific and sensitive for H. pylori in relation to histology.
Histology
Accutest H. pylori Urease Test + 20 0
- 0 80
Sensitivity=100% (95% Confidence lnterval* = .9705 -.1000) Specificity=100% (95% Confidence lnterval* = .9705 -.1000)
During 2008 and 2009 a study was conducted to demonstrate an insignificant risk of an erroneous result and support the issuance of a CLIA waiver by the FDA for the product Accutest H. pylori Urease Test. In order to effectively evaluate this test a total of 300 actual patient biopsies and 140 contrived biopsies were tested at 3 separate sites with no less than 3 users per site. The users were blinded as to the results and asked to perform the test using only the provided quick reference instructions. For clinical biopsy specimens, the results showed a positive agreement of 91.2% and a negative agreement of 98.7% compared to histology. For contrived specimens, the results showed positive agreement of 97.2% and a negative agreement of 95.5% compared to expected results.
FLEX STUDIES Samples of Accutest H. pylori Urease Test have been stored for a minimum of 2 years in a various conditions and temperatures ranging from 40 degrees Fahrenheit to 85 degrees Fahrenheit. One of the testing sites was a non- air conditioned, non-humidity controlled warehouse, which allowed for continuously varying temperatures as well as varying humidity levels up to above 80% relative humidity. These samples were tested on a monthly basis and compared to duplicate samples stored in a humidity controlled and temperature controlled environment. Samples were given a pass rating if the results corresponded with the duplicate samples as well as prepared controls. The prepared controls were a solution of urease from Jack bean in distilled H20. In all cases the tests performed as intended.
PERFORMANCE NOT MEETING SPECIFICATIONS: If the Accutest H. pylori Urease Test test does not perform as outlined in these instructions, please contact Jant Pharmacal Corporation Customer Service at 800-676-5565. BIBLIOGRAPHY
Bulletin number CDI 86/25, Communicable Diseases Branch, Department of Health, ACT, 15 Dec, 1986, 4-7. Dooley C P, and Cohen H. The clinical significance of Campylobacter pylori. Ann Intern Med 19881- 108(l)-.70-79. Jones D M et al. Antibody to the gastric Campylobacter-like organism (C.pyloridis). Clinical correlations and distribution normal population. J Med Microbiol 1986 1- 22:57-62. Kaldor J et al. Immunoblot confirmation of immune response to C.pylori in patients with duodenal ulcers. Med J Aust 1986; 145-. 133-135. Marshall B J, Warren J R. Unidentified curved bacilli in the stomach of patients with gastritis and peptic ulceration. Lancet 1984; 1-.1311-1315. Marshall B J. Campylobacter pyloridis and Gastritis. J Infect Dis 1986-1 153(4)-.650-657. Abstracts of papers Gastroenterology 1988; 94(5): Part 2, supporting the association of C.pylori with upper gastrointestinal disorders: Attar B et al. The incidence of Campylobacter pylori infection among patients of GI-endoscopy unit in a metropolitan hospital. A Barthel J S et al. The distribution of Campylobacter pylori (Cp) and gastric mucosal histopathology in symptomatic volunteers. A25. de Korwin J D et al. Campylobacter pylori (Cp) is associated with intense chronic gastritis in the antrum as in the fundum. A93. Malfertheiner P et al. Bismuth subsalicylate (B.S.) treatment in C.pylori related chronic erosive gastritis. A279. , Martin D F et al. Rule out peptic ulcer disease with a question and a blood test. A285. Raedsch R et al. Elevated concenfrations of not amidated and secondary bile acids and of lysolecithin in gastric juice at presence of Campylobacter pylori. A364. Tolia V. Role of Campylobacter pylori (Cp) in children with recurrent abdominal pain (RAP). A463. GENERAL REFERENCES: See Abstracts on Campylobacter pylori from a Multi-disciplinary workshop. Keystone Resort, Colorado, July 28-31, 1988, Director Peterson, W L. University of Texas Health Sciences Centre, Dallas. See Abstracts of Papers relating to Campylobacter pylori. Gastroenterology 1988; 94(5): Part 2. Articles on Ulcer Disease for the General Practitioner by various authors. Australia Patient Management 1987- 11(4)-.23-77. Ainsley C C et al. Outpatient endoscopic survey of smoking and peptic ulcer. Gut 1986; (6)-.648-51. Blaser M J. Type B gastritis, aging and Campylobacter pylori. Arch Intern Med 1988-1 148:1021-1022. Bonnevie 0. Changing demographics of peptic ulcer disease. Digestive Diseases and Sciences 1985-1 30(11) Suppl-.85-145. Garau G et al. Epidemiological findings on gastric and duodenal ulcer in the pre- and post-cimetidine era. A study of 2,119 cases. Minerva Dietol Gastroenterol 1987: 33(3):209-216. Hugh T. 70,000 with peptic ulcers. Aust Dr 1985, 23 Sept:13. Jones R. Upper gastrointestinal endoscopy - a view from general practice. Journal of the Royal College of General Practitioners 1986-1 Jan:7-8. Langman M J S. The changing face of peptic ulceration. Scand J Gastroenterol 1987; Suppl 136:37-40. Langman M J S. The Epidemiology of Chronic Digestive Disease. Edward Arnold, London, 1979. Price A B et al. Campylobacter pyloridis in peptic ulcer disease Gut 1985; 26-.1183-1188. The Bulletin. The dollar scope. June 21, 1988, 56.
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JANT Pharmacal Corporation 16530 Ventura Blvd., Suite 512 Encino, CA 91436 Phone: (800) 676-