BACKGROUND: Detection of Helicobacter pylori is usually performed by culture, polymerase chain reaction (PCR), histology, or urease test on gastric biopsy samples. Although methods based on feces are non-invasive, their sensitivity has been relatively low. In this study, to improve its sensitivity, immunomagnetic separation (IMS) was used as a pre-PCR step for direct detection of H. pylori in feces. METHODS: Fresh fecal samples were taken from 72 patients attending for endoscopy. Of these, 57 patients had a positive H. pylori status according to the results of culture, histology, and PCR on gastric biopsy samples. Anti-H. pylori antibody-sensitized immunomagnetic beads were used to concentrate the bacteria. PCR was then performed to detect the H. pylori urease A-encoding gene. RESULTS: Of the 57 H. pylori-positive patients, 35 (61.4%) had positive fecal samples by IMS-based PCR method. None of the 15 H. pylori-negative patients had positive fecal samples. The sensitivity of this method was 61.4%, and the specificity 100.0%. CONCLUSIONS: This study confirms that non-invasive diagnosis of H. pylori infection could be made from feces by using IMS-based PCR.
BACKGROUND: Detection of Helicobacter pylori is usually performed by culture, polymerase chain reaction (PCR), histology, or urease test on gastric biopsy samples. Although methods based on feces are non-invasive, their sensitivity has been relatively low. In this study, to improve its sensitivity, immunomagnetic separation (IMS) was used as a pre-PCR step for direct detection of H. pylori in feces. METHODS: Fresh fecal samples were taken from 72 patients attending for endoscopy. Of these, 57 patients had a positive H. pylori status according to the results of culture, histology, and PCR on gastric biopsy samples. Anti-H. pylori antibody-sensitized immunomagnetic beads were used to concentrate the bacteria. PCR was then performed to detect the H. pylori urease A-encoding gene. RESULTS: Of the 57 H. pylori-positive patients, 35 (61.4%) had positive fecal samples by IMS-based PCR method. None of the 15 H. pylori-negative patients had positive fecal samples. The sensitivity of this method was 61.4%, and the specificity 100.0%. CONCLUSIONS: This study confirms that non-invasive diagnosis of H. pyloriinfection could be made from feces by using IMS-based PCR.
Authors: C Goosen; J Theron; M Ntsala; F F Maree; A Olckers; S J Botha; A J Lastovica; S W van der Merwe Journal: J Clin Microbiol Date: 2002-01 Impact factor: 5.948