Polymerase chain reaction in the detection of Helicobacter pylori infection

To determine the presence of Helicobacter pylori (H. pylori) infection, in patients suffering from gastritis and peptic ulcer disease by polymerase chain reaction (PCR) and correlate the results with the histological diagnosis.

Analytical, comparative study.

Section of Gastroenterology, Department of Medicine and Pathology, Aga Khan University Hospital and School of Life Sciences and Chemical Technology, Ngee Ann Polytechnic, Singapore from November, 2001 to December, 2002.

Gastric antral biopsies were obtained from 64 patients attending the Gastroenterology Section of Aga Khan University Hospital. Patients on nonsteroidal-anti-inflammatory drugs (NSAIDS) were excluded. Gastric biopsies were sent for histopathology and used for DNA extraction and PCR amplification of H. pylori 16S ribosomal RNA (rRNA) gene. Results were compared and statistically analyzed.

H. pylori were not visible by histology in 57.6 % (34/59) and could be seen in 42.4 % (25/59). PCR test was negative for H. pylori DNA in 44.1 % (26/59) and positive in 55.9 % (33/59) with p<0.001.

PCR H. pylori DNA is a sensitive method for the diagnosis of H. pylori infection and its use as a diagnostic tool along with histology increases the detection rate of H. pylori infection. Two different staining methods for the organism should be used to avoid missing diagnosis of H. pylori infection.