INTRODUCTIONThe use of an additional biopsy from the gastric body may help improve the detection of Helicobacter pylori during endoscopy. This study aimed to determine whether such an additional biopsy is necessary in routine rapid urease test (RUT), and whether acid suppression and antibiotic therapy affect RUT results.

METHODSPatients recruited had two gastric mucosal biopsies taken - one from the gastric antrum and the other from the gastric body. Each biopsy was placed into separate RUT kits. Information on previous or current use of proton-pump inhibitors, H2 receptor antagonist, bismuth and antibiotics was obtained. Patients on any of those drugs one week prior to endoscopy were considered to have a positive drug history (PDH).

RESULTSOf the 400 patients recruited, 311 had negative RUTs and 89 had at least one positive RUT. Between the PDH and negative drug history (NDH) groups, there was a significant difference in the distribution of the location of the biopsies that yielded positive RUTs (p = 0.023). The NDH group had a higher proportion of patients who had positive RUTs for both locations, whereas the PDH group had a higher proportion of patients who had positive RUTs for only one location.

CONCLUSIONAs RUT results are significantly affected by the use of acid suppression and antibiotic therapies, biopsies for RUT should be taken from both the gastric antrum and body to minimise false negative results.

Adult ; Aged ; Antacids ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Endoscopy ; Endoscopy, Gastrointestinal ; Female ; Gastric Mucosa ; microbiology ; pathology ; Gastrointestinal Diseases ; diagnosis ; epidemiology ; microbiology ; Helicobacter Infections ; diagnosis ; Helicobacter pylori ; drug effects ; isolation & purification ; History, Ancient ; Humans ; Middle Aged ; Singapore ; epidemiology ; Urease ; analysis