SK Tiwari, AA Khan, KS Ahmed, I Ahmed, F Kauser, MA Hussain, SM Ali, A Alvi, A Habeeb, Z Abid, N Ahmed, CM Habibullah
Correspondence: Prof C M Habibullah, cmhabib@rediffmail.com
ABSTRACT
Introduction Current guidelines that recommend Helicobacter pylori eradication treatment without endoscopy in selected patients underscore the importance of non-invasive testing. The accuracy of saliva as a non-invasive specimen was compared with that of invasive tests in pretreatment diagnosis of H. pylori infection.
Methods One hundred patients undergoing gastroscopy were grouped into 80 symptomatic and 20 asymptomatic subjects and were investigated for the presence of H. pylori in saliva and stomach. Samples tested comprised saliva and gastric biopsies collected from each patient. Exclusion criteria were history of peptic ulcer, bleeding ulcer, cancer or recent use of antibiotics, proton pump inhibitors and non-steroidal anti-inflammatory drugs. Two sets of primers homologous to 534 bp fragment of H. pylori DNA, which have been shown previously to be highly specific and sensitive, were used for the polymerase chain reaction (PCR) amplification.
Results 72 (90 percent) of the symptomatic group and 10 asymptomatic subjects were infected with H. pylori in the stomach as determined by histology and direct PCR amplification of biopsy DNA obtained from each subject. H. pylori DNA was identified in the saliva of 70 (87.5 percent) symptomatic subjects and 12 (60 percent) asymptomatic control subjects.
Conclusion High rates of detection using saliva as a specimen indicate that saliva of the infected person could serve as a reliable non-invasive alternative to detect the presence of H. pylori infection in comparison to the currently available standard diagnostic tests.
Keywords: duodenal ulcer, gastritis, Helicobacter pylori, polymerase chain reaction saliva, 16S ribosomal RNA genes
Singapore Med J 2005; 46(5): 224-228
