Loop-mediated isothermal amplification of Neisseria gonorrhoeae porA pseudogene: a rapid and reliable method to detect gonorrhea

AMB Express. 2017 Dec;7(1):48. doi: 10.1186/s13568-017-0349-6. Epub 2017 Feb 23.

Abstract

Background and objective: Gonorrhea is a sexually transmitted disease caused by the bacterium Neisseria gonorrhoeae. Rapid detection is crucial for effective prevention and treatment. This study developed and tested a low-cost effective method for detecting N. gonorrhoeae, especially in developing countries.

Methods: DNA from a N. gonorrhoeae standard strain, as well as from 26 genital secretion samples of gonorrhea patients, were isolated and used for loop-mediated isothermal amplification (LAMP) assay, which was conducted using either an automatic real-time PCR analyzer or a water bath. The amplified porA pseudogene sequence was compared with the NCBI database and the LAMP results were compared with that of the traditional culture method for its sensitivity and specificity.

Results: LAMP was able to detect Neisseria DNA at a concentration as low as 1 pg/µL (1 × 103 CFU/mL cells). The LAMP assay results obtained using an automatic real-time PCR analyzer was similar to that of the water bath. Relative to traditional culture, the sensitivity and specificity of the LAMP assay were 94.7 and 85.7%, respectively.

Conclusion: LAMP was sensitive and reliable for detecting the porA gene of N. gonorrhoeae. It could be used as a rapid, low cost, and effective method for detecting N. gonorrhoeae.

Keywords: Gonorrhea; LAMP; Neisseria gonorrhoeae detection; porA gene.