Assessment of real-time PCR for diagnosis of Mycoplasma pneumoniae pneumonia in pediatric patients

We developed a real-time PCR to detect Mycoplasma pneumoniae with a primer set designed for the 16S rRNA gene. Clinical samples (n = 937) were collected from children with community-acquired pneumonia between April 2002 and March 2004 at 12 Japanese medical institutions. Sensitivity of real-time PCR was calculated as 10 colony-forming units per reaction tube using a pMP01 plasmid carrying a 225-bp target DNA fragment of the 16S rRNA gene in M. pneumoniae M129, a standard strain. Results, obtained within 2 h, were compared with those of conventional culture and serologic methods. Of all cases tested, 151 (16.4%) and 129 (13.8%) were positive for M. pneumoniae by real-time PCR and by culture, respectively. Among the 151 cases, almost all of those tested serologically by passive agglutination showed a rise in M. pneumoniae antibody titre between acute and convalescent sera. We conclude that this real-time PCR can identify M. pneumoniae rapidly and fulfills the need for rapid identification, high sensitivity, and high specificity.