Comparison of polymerase chain reaction and histopathology for the detection of Helicobacter pylori in gastric biopsies

Abstract

Using data from a Venezuelan cohort of 1,948 adults, the gastric detection of Helicobacter pylori ( H. pylori ) by polymerase chain reaction (PCR) of the vacA gene in 1 antral biopsy was compared to the detection of H. pylori by histopathology (hematoxylin–eosin and Giemsa staining) in 5 biopsies (antrum and corpus). Overall, H. pylori was detected in 85% and 95% of the subjects by PCR and histopathology, respectively. When results were analyzed by severity of precancerous lesions, PCR on 1 biopsy detected the bacteria less often than histopathology on 5 biopsies in subjects with normal gastric mucosa and non‐atrophic gastritis. However, in subjects with the most severe lesions (intestinal metaplasia type III and dysplasia), PCR on 1 biopsy detected H. pylori as often as histopathology on 5 biopsies, and significantly more often than histopathology on a single biopsy. In conclusion, these findings confirm that histopathology on 5 biopsies is an accurate tool for H. pylori detection in most subjects, compared to the PCR method on 1 biopsy. Nevertheless, the elevated sensitivity of PCR for detecting the bacteria in advanced precancerous lesions, and the possibility to use PCR to distinguish between cagA‐positive and cagA‐negative strains, makes the PCR technique especially useful in studies of stomach cancer.