Development and Diagnostic Evaluation of Loop-Mediated Isothermal Amplification Using a New Gene Target for Rapid Detection of Helicobacter pylori

Jundishapur J Microbiol. 2016 Feb 15;9(5):e28831. doi: 10.5812/jjm.28831. eCollection 2016 May.

Abstract

Background: Helicobacter pylori cause chronic gastritis and subsequent diseases like gastric and duodenal ulcers and gastric adenocarcinoma. Current methods for detecting H. pylori have several disadvantages and it is of utmost importance to develop a simple, quick, accurate, and cost-effective diagnostic test.

Objectives: The aim of this study was to set up and evaluate a diagnostic value of loop- mediated isothermal amplification (LAMP) for detecting H. pylori.

Patients and methods: The analytical sensitivity values (limit of detection) of LAMP and polymerase chain reaction (PCR) were determined using serial dilutions of H. pylori DNA. Analytical specificity of the methods using new designed primers targeted ureC gene was also determined.

Results: The detection limits of the LAMP and PCR assay were similar and were 10 fg of pure DNA of H. pylori, which is equal to 6 copy numbers of H. pylori genome. Analytical specificity of the tests was 100% because the tests were positive only with H. pylori DNA.

Conclusions: The analytical sensitivity of LAMP and PCR methods, using the designed primers, was 8 times more than any other reported methods. The designed methods are specific and sensitive for detection of H. pylori in different clinical and environmental samples.

Keywords: Analytical Specificity; Detection Limit; Helicobacter pylori; Loop-Mediated Isothermal Amplification.