Express fluorescence in situ hybridization methods for the detection of Staphylococcus aureus.
BACKGROUND
As a proof-of-concept, the feasibility of detecting Staphylococcus aureus faster than previous whole-cell fluorescent in situ hybridization (FISH) methods was tested.


METHODS
Isolates of Staphylococcus were treated with three rapid slide-based FISH protocols and DNA probes. Protocols were shortened by optimizing, combining or omitting steps.


RESULTS
All FISH protocols detected S. aureus and not the phenotypically similar Staphylococcus epidermidis. The express FISH assay was completed in 24 minutes. The one-step FISH assay with NaCl and the one-step with phosphate buffered saline (PBS) assay took 19 minutes, but yielded a weaker signal.


CONCLUSIONS
The exploratory study identified S. aureus two to three times faster than previous methods. Additional testing in a clinical laboratory scenario (for example with positive blood-culture bottles) is warranted.
Faculty of Science, Macquarie University, Sydney, Australia. tomxlawson@gmail.com
Thomas S
TS
Lawson
Russell E
RE
Connally
Subramanyam
S
Vemulpad
James A
JA
Piper
D004269:DNA, Bacterial / Q000032:analysis; D057166:High-Throughput Screening Assays; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D013203:Staphylococcal Infections / Q000175:diagnosis* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000166:cytology / Q000235:genetics / Q000302:isolation & purification*; D013212:Staphylococcus epidermidis / Q000235:genetics / Q000302:isolation & purification; D013997:Time Factors
D004269:DNA, Bacterial