Application of flow cytometry for the identification of Staphylococcus epidermidis by peptide nucleic acid fluorescence in situ hybridization (PNA FISH) in blood samples
- 606 Downloads
Staphylococcus epidermidis is considered to be one of the most common causes of nosocomial bloodstream infections, particularly in immune-compromised individuals. Here, we report the development and application of a novel peptide nucleic acid probe for the specific detection of S. epidermidis by fluorescence in situ hybridization. The theoretical estimates of probe matching specificity and sensitivity were 89 and 87%, respectively. More importantly, the probe was shown not to hybridize with closely related species such as Staphylococcus aureus. The method was subsequently successfully adapted for the detection of S. epidermidis in mixed-species blood cultures both by microscopy and flow cytometry.
KeywordsStaphylococcus epidermidis Bloodstream infection Flow cytometry FISH Nanodiagnostics Permeabilization
This work was supported by the Portuguese Institute Fundação para a Ciência e Tecnologia (PhD Fellowship SFRH/BD/29297/2006 and Post-Doc Fellowship SFRH/BPD/42208/2007).
- Almeida C, Azevedo NF, Iversen C, Fanning S, Keevil CW, Vieira MJ (2009) Development and application of a novel peptide nucleic acid probe for the specific detection of Cronobacter (Enterobacter sakazakii) in powdered infant formula. Appl Environ Microbiol 75(9):2925–2930PubMedCrossRefGoogle Scholar
- Haimi-Cohen Y, Vellozzi EM, Rubin LG (2002) Initial concentration of Staphylococcus epidermidis in simulated pediatric blood cultures correlates with time to positive results with the automated, continuously monitored BACTEC blood culture system. J Clin Microbiol 40:898–901PubMedCrossRefGoogle Scholar
- Jukes L, Mikhail J, Bome-Mannathoko N, Hadfield SJ, Harris LG, El-Bouri K, Davies AP, Mack D (2010) Rapid differentiation of Staphylococcus aureus, Staphylococcus epidermidis and other coagulase-negative staphylococci and methicillin susceptibility testing directly from growth-positive blood cultures by multiplex real-time PCR. J Med Microbiol 59:1456–1461PubMedCrossRefGoogle Scholar
- Stender H, Lund K, Petersen KH, Rasmussen OF, Hongmanee P, Miorner H, Godtfredsen SE (1999) Fluorescence in situ hybridization assay using peptide nucleic acid probes for differentiation between tuberculous and nontuberculous mycobacterium species in smears of Mycobacterium cultures. J Clin Microbiol 37:2760–2765PubMedGoogle Scholar