Comparing efficiency between conventional and molecular methods for detecting Legionella pneumophilia in dental unit waterline systems

The aim of our study was to detect the prevalence of Legionella pneumophilia (L. pneumophilia) in DUWLS using standard culture technique (SCT) and the real-time polymerase chain reaction (PCR) method in order to assess the risk of L. pneumophilia contamination within a dental setting. A total of 65 water samples were collected from 16 dental units and one cold water supply system from all clinical departments. L. pneumophilia could not be detected in any of the water samples using the standard SCT (0%), whereas L. pneumophilia was detected using real time PCR in three (4.6%) water samples collected from the tap system. Following the detection of L. pneumophilia, the tap systems were disinfected with surface disinfectant and water samples were recollected. The recollected water samples following disinfection were negative for L. pneumophilia once analyzed using culture and real time PCR technique. Although the culture method using BCYE media is the ‘gold standard’ for the detection of L. pneumophilia; Real Time PCR analysis may also be a quick, useful, and sensitive method for the detection of L. pneumophilia in order to control and prevent possible infections that may arise in the dental setting.