OBJECTIVES: We previously showed that real-time PCR was a reliable technique for coupled detection of Helicobacter pylori and clarithromycin resistance mutations directly from biopsies. After one year of use, we compared its performances to those of histology, which remains the most employed method for H. pylori detection from gastric biopsies. MATERIALS AND METHODS: 518 subjects underwent endoscopy during the year 2003 with biopsies taken for H. pylori detection by histology, PCR, and in case of discrepancy between the two techniques, by culture. RESULTS: The prevalence of infection, defined as positive PCR and histology, and in case of discrepancy as a positive culture, was 30% (163/518). The percentage of concordance between the two tests was 87.8% (455/518). The sensitivity, specificity, positive and negative predictive values of PCR were 98.2%, 97.5%, 94.7%, and 99.1%, respectively. The corresponding performances of histology were 87.7%, 91.3%, 82.2%, and 94.2%, respectively (p<0.001). The prevalence of clarithromycin resistance was 30%. CONCLUSIONS: PCR is more accurate in routine than histology and permits easy determination of clarithromycin resistance, which is useful in countries like France where the prevalence of resistance is high.
OBJECTIVES: We previously showed that real-time PCR was a reliable technique for coupled detection of Helicobacter pylori and clarithromycin resistance mutations directly from biopsies. After one year of use, we compared its performances to those of histology, which remains the most employed method for H. pylori detection from gastric biopsies. MATERIALS AND METHODS: 518 subjects underwent endoscopy during the year 2003 with biopsies taken for H. pylori detection by histology, PCR, and in case of discrepancy between the two techniques, by culture. RESULTS: The prevalence of infection, defined as positive PCR and histology, and in case of discrepancy as a positive culture, was 30% (163/518). The percentage of concordance between the two tests was 87.8% (455/518). The sensitivity, specificity, positive and negative predictive values of PCR were 98.2%, 97.5%, 94.7%, and 99.1%, respectively. The corresponding performances of histology were 87.7%, 91.3%, 82.2%, and 94.2%, respectively (p<0.001). The prevalence of clarithromycin resistance was 30%. CONCLUSIONS: PCR is more accurate in routine than histology and permits easy determination of clarithromycin resistance, which is useful in countries like France where the prevalence of resistance is high.