Identification of Staphylococcus epidermidis in the Clinical Microbiology Laboratory by Molecular Methods

Biochemical assays for the phenotypic identification of coagulase-negative staphylococci in the clinical microbiology laboratory have been well described in previous publications (Becker and Von Eiff Manual of Clinical Microbiology, ASM Press, Washington, pp. 308–330, 2011; Kloos and Wolfshohl J Clin Microbiol 16:509–516, 1982). This discussion focuses on identification of Staphylococcus epidermidis through molecular and proteomic methods. Molecular assays have been shown to be more discriminatory between the coagulase-negative staphylococcal species than are phenotypic assays (Zadoks and Watts Vet Microbiol 134:20–28, 2009; Sheraba et al. BMC Res Notes 3:278, 2010; Patteet et al. Eur J Clin Microbiol Infect Dis 31:747–751, 2012). The molecular and proteomic methods that have shown the greatest utilization potential within the clinical laboratory are as follows: PCR amplification and sequencing of discriminatory genes, real-time polymerase chain reaction with species-specific probes in conjunction with a melt-curve analysis, fluorescence in situ hybridization, and matrix-assisted laser desorption-ionization time-of-flight mass spectrometry.