Development and evaluation of a loop-mediated isothermal amplification method for the rapid detection of Chlamydophila pneumoniae.

We developed a loop-mediated isothermal amplification (LAMP) method to detect Chlamydophila pneumoniae infection. This assay exclusively amplified C. pneumoniae sequences and no cross-reactivity was observed for other Chlamydia species. The detection limit for this assay was found to be ten elementary bodies in 25 min, as observed in a real-time turbidimeter and electrophoretic analysis. The specificity of the LAMP reaction was confirmed by restriction endonuclease analysis, as well as direct sequencing of the amplified product. Among nasopharyngeal swab specimens from 120 patients with acute respiratory tract infections and 40 healthy individuals, the LAMP results showed 100% agreement with the results of real-time polymerase chain reaction (PCR) assays.