Evaluation of a real-time PCR hybridization assay for rapid detection of Legionella pneumophila in hospital and environmental water samples.
A real-time LightCycler assay for Legionella pneumophila was evaluated with 120 water samples potentially contaminated with PCR inhibitors. Results were obtained within five hours, with a detection limit equivalent to 800 cells/L. However, 11 of 22 culture-positive samples containing < 100 CFU/L were also positive by LightCycler assay, indicating the presence of significant numbers of non-viable cells. Following extraction, amplification inhibitors remained in four culture-positive samples, but only one contained > 800 CFU/L. The assay seemed suitable for rapidly screening large sample numbers for heavy contamination with L. pneumophila, but conventional culture should continue to be used to detect low contamination levels.
Levi
K
K
Molecular Diagnostics & Typing Unit, Public Health Laboratory, University Hospital, Queen's Medical Centre, Nottingham NG7 2UH, UK.
Smedley
J
J
Towner
K J
KJ
D016952:Legionella pneumophila / Q000235:genetics / Q000302:isolation & purification*; D007877:Legionnaires' Disease / Q000175:diagnosis*; D016133:Polymerase Chain Reaction; D014871:Water Microbiology; D014881:Water Supply / Q000032:analysis*