Pediatr Gastroenterol Hepatol Nutr.  2013 Mar;16(1):34-40. 10.5223/pghn.2013.16.1.34.

Influencing Factors to Results of the Urease Test: Age, Sampling Site, Histopathologic Findings, and Density of Helicobacter pylori

• Seo JH
• Youn HS
• Park JJ
• Yeom JS
• Park JS
• Jun JS
• Lim JY
• Park CH
• Woo HO
• Ko GH
• Baik SC
• Lee WK
• Cho MJ
• Rhee KH

• KMID: 1428805
• DOI: http://doi.org/10.5223/pghn.2013.16.1.34

Abstract

PURPOSE
We investigated the positivity rate and the time period to the positive color change of the urease test in children and adults and assessed the correlation of the urease test to histopathologic findings.
METHODS
From 1995 to 2000, endoscopic biopsies of the antrum and body were collected from 811 children and 224 adults and subjected to urease tests and histopathology.
RESULTS
The positivity rate of the urease test was 49.4% for 0-4 years, 48.4% for 5-9 years, 47.3% for 10-15 years, and 62.5% for 20-29 years in the antrum. The positivity rate was 85.1% in 0-4 years, 82.3% in 5-9 years, 74.7% in 10-15 years, and 74.1% in 20-29 years for the body. In the antrum, the highest positivity rate was <1 hour for the group aged 10-29 years and 6-24 hours in the group <10 years old (p<0.0001). In the body, the highest positivity rate was <1 hour in adults and 6-24 hours in children (p<0.0001). The proportions of the positive reactions within 1 hour were similar for the antrum and the body. In the cases of more severe chronic gastritis, active gastritis, and Helicobacter pylori infiltration, a positive urease test reaction occurred more quickly (p<0.0001).
CONCLUSION
There were significant differences in urease tests according to age and sampling site. The discrepancy between the antrum and the body was greater in younger children. These results might be related to the low density and patchy distribution of bacteria in children and in the body.

Keyword

Urease test; Helicobacter pylori infection; Age; Pathology

MeSH Terms

Adult
Aged
Bacteria
Biopsy
Child
Gastritis
Helicobacter
Helicobacter pylori
Humans
Urease
Urease

Figure

• 

  Fig. 1 The positivity rate and positive timing of the urease test both in the antrum and body according to age. The positivity rate of the urease test in the antrum was higher in 20-29 years group comparing with that in other three age groups, and the positivity rate of the urease test in the body decreased with increasing age (p<0.0001). The highest positivity timing was within 1 hour in the 20-29 years group, and within 6-24 hours in children (p<0.0001). The proportions of positive reactions within 1 hour were similar for the antrum and body in all groups.

Reference

1. Malaty HM, El-Kasabany A, Graham DY, Miller CC, Reddy SG, Srinivasan SR, et al. Age at acquisition of Helicobacter pylori infection: a follow-up study from infancy to adulthood. Lancet. 2002. 359:931–935.

2. Ko GH, Park CK, Choi CS, Park HB, Lee JH, Lee HJ, et al. Helicobacter pylori infection and histopathological features of gastric mucosa. Korean J Pathol. 1996. 30:199–209.

3. Ohkusa T, Miwa H, Endo S, Okayasu I, Sato N. Helicobacter pylori is a fragile bacteria when stored at low and ultra-low temperatures. J Gastroenterol Hepatol. 2004. 19:200–204.

4. Dixon MF, Genta RM, Yardley JH, Correa P. Classification and grading of gastritis. The updated Sydney System. International Workshop on the Histopathology of Gastritis, Houston 1994. Am J Surg Pathol. 1996. 20:1161–1181.

5. Midolo P, Marshall BJ. Accurate diagnosis of Helicobacter pylori. Urease tests. Gastroenterol Clin North Am. 2000. 29:871–878.

6. Graham DY. Helicobacter pylori and the endoscopist: whether to diagnose. Gastrointest Endosc. 1991. 37:577–579.

7. Madani S, Rabah R, Tolia V. Diagnosis of Helicobacter pylori infection from antral biopsies in pediatric patients is urease test that reliable? Dig Dis Sci. 2000. 45:1233–1237.

8. Dondi E, Rapa A, Boldorini R, Fonio P, Zanetta S, Oderda G. High accuracy of noninvasive tests to diagnose Helicobacter pylori infection in very young children. J Pediatr. 2006. 149:817–821.

9. Elitsur Y, Hill I, Lichtman SN, Rosenberg AJ. Prospective comparison of rapid urease tests (PyloriTek, CLO test) for the diagnosis of Helicobacter pylori infection in symptomatic children: a pediatric multicenter study. Am J Gastroenterol. 1998. 93:217–219.

10. Drumm B. Helicobacter pylori in the pediatric patient. Gastroenterol Clin North Am. 1993. 22:169–182.

11. Carelli AP, Patrício FR, Kawakami E. Carditis is related to Helicobacter pylori infection in dyspeptic children and adolescents. Dig Liver Dis. 2007. 39:117–121.

12. Siddique I, Al-Mekhaizeem K, Alateeqi N, Memon A, Hasan F. Diagnosis of Helicobacter pylori: improving the sensitivity of CLOtest by increasing the number of gastric antral biopsies. J Clin Gastroenterol. 2008. 42:356–360.

13. Woo JS, el-Zimaity HM, Genta RM, Yousfi MM, Graham DY. The best gastric site for obtaining a positive rapid ureas test. Helicobacter. 1996. 1:256–259.

14. Tang JH, Liu NJ, Cheng HT, Lee CS, Chu YY, Sung KF, et al. Endoscopic diagnosis of Helicobacter pylori infection by rapid urease test in bleeding peptic ulcers: a prospective case-control study. J Clin Gastroenterol. 2009. 43:133–139.

15. Park JS. Comparison of positive rate of urease tests with different number of biopsy specimens and different biopsy sites according to the age [Unpublished doctoral dissertation]. 2005. Jinju: Gyeongsang National University.

16. Gisbert JP, Abraira V. Accuracy of Helicobacter pylori diagnostic tests in patients with bleeding peptic ulcer: a systematic review and meta-analysis. Am J Gastroenterol. 2006. 101:848–863.

17. Roma-Giannikou E, Roubani A, Sgouras DN, Panayiotou J, van-Vliet C, Polyzos A, et al. Endoscopic tests for the diagnosis of Helicobacter pylori infection in children: Validation of rapid urease test. Helicobacter. 2010. 15:227–232.

18. Bravo LE, Realpe JL, Campo C, Mera R, Correa P. Effects of acid suppression and bismuth medications on the performance of diagnostic tests for Helicobacter pylori infection. Am J Gastroenterol. 1999. 94:2380–2383.

19. El-Omar EM, Oien K, El-Nujumi A, Gillen D, Wirz A, Dahill S, et al. Helicobacter pylori infection and chronic gastric acid hyposecretion. Gastroenterology. 1997. 113:15–24.

20. Oderda G, Dell'Olio D, Morra I, Ansaldi N. Rapid urease test (CLO-Test) for early detection of Campylobacter pylori infection in children. Am J Gastroenterol. 1988. 83:792.

21. Engstrand L, Rosberg K, Hübinette R, Berglindh T, Rolfsen W, Gustavsson S. Topographic mapping of Helicobacter pylori colonization in long-term-infected pigs. Infect Immun. 1992. 60:653–656.