Evaluation of Diagnostic Performance of Culture, Rapid Urease Test and Histopathology in the Diagnosis of Helicobacter pylori Infection, and In Vitro Activity of Various Antimicrobials Against Helicobacter pylori

Abstract

Objective: The aim of this study, is to investigate the presence of Helicobacter pylori (H. pylori) infection by culture, histology and rapid urease test (RUT) in gastric antrum biopsy samples taken from patients presenting with dyspeptic complaints and to determine the resistance of the isolates to amoxicillin, clarithromycin, levofloxacin and metronida-zole by antibiotic gradient method (E-test).Methods: Microbiological and histopathological examinations of 278 biopsy specimens taken from antrum and corpus regions were performed. The presence of H. pylori in biopsy samples was investigated by culture, histology and RUT. Antimicrobial resistance of the isolates against amoxicillin, clarithromycin, levofloxacin and metronidazole was de-termined by antibiotic gradient method. Sensitivity and specificity of histology and RUT were calculated by accepting culture as the gold standard. Sensitivity and specificity for culture was also calculated by taking the co-positivity of both histology and RUT as the gold standard.Results: H. pylori positivity was detected in 140 of 278 patients with culture, 174 with histology, and 191 with RUT. Sensitivity and specificity of the culture, histology and RUT methods of the patients were 76.5% and 88.3%, 87.8% and 63%, 94.2% and 57.2%, respectively. Antibiotic resistance was investigated by antibiotic gradient method in 140 H. pylori strains isolated from culture. The resistance rates of H. pylori strains to the amoxillin, clarithromycin, levoflox-acin and metronidazole were detected as 9 (%6.4), 22 (%15.7), 17 (%12.1), 57 (%40.7), respectively.Conclusions: In the study, RUT was found to be the most sensitive test among culture, histology and RUT methods. Although the specificity of the culture method was high, its sensitivity was found to be quite low compared to other methods. The low sensitivity of H. pylori culture may be caused by factors that affect the chances of direct isolation such as dealing with a fastidious microorganism, clinical sample retrieval and transport conditions.