CLO vs histology: optimal numbers and site of gastric biopsies to diagnose Helicobacter pylori

Eur J Gastroenterol Hepatol. 2001 Apr;13(4):387-90. doi: 10.1097/00042737-200104000-00014.


Objective: To determine the optimal numbers and sites of biopsies required for diagnosis of Helicobacter pylori by using the CLOtest and comparing the results with those of a routine histological assessment in a district general hospital (DGH) setting.

Methods: A prospective study comparing the sensitivity of the CLOtest containing one antral (CLO 1), two antral (CLO 2) and two antral and one body biopsy (CLO 3), and with histological examination for H. pylori. Consecutive patients undergoing upper gastrointestinal endoscopy (UGIE) at Stepping Hill Hospital, Stockport, UK, who had evidence of gastritis, gastric ulcer, duodenitis or duodenal ulcer were included in the study.

Results: Ninety-six patients were biopsied. Forty were positive on at least one of the CLOtests; of these, nine were negative on histological assessment. Of these nine, two were positive on all CLOtests and seven were positive only on CLO 3. One was positive on histology but negative on all CLOtests. This study showed that CLO 3 was more sensitive than CLO 1 (P = 0.004), CLO 2 (P = 0.016) and histology (P = 0.022). There was no significant difference between CLO 1 and CLO 2 (P = 0.500), CLO 1 and histology (P = 1.000), CLO 2 and histology (P = 1.00).

Conclusion: We feel that in a busy clinical setting, taking two antral and one body biopsy in a single CLOtest is superior to routine histological assessment for the detection of H. pylori, with resulting cost saving.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Biopsy / methods
  • Female
  • Helicobacter Infections / diagnosis*
  • Helicobacter pylori / isolation & purification*
  • Humans
  • Male
  • Middle Aged
  • Prospective Studies
  • Pyloric Antrum / microbiology*
  • Pyloric Antrum / pathology*
  • Urease / analysis


  • Urease