Simplified scheme for species identification and antibiotic susceptibilities of coagulase negative staphylococci isolated from clinical specimens

Coagulase negative staphylococci (CONS) species identification is difficult for most clinical laboratories. The schemes proposed by Kloos and Schleifer is the reference method used for the identification of staphylococcal species and subspecies. It requires the utilization of a large number of biochemical tests. Antibiotic susceptibility testing was done by Kirby-Bauer disk diffusion method. Out of the total 51 CONS isolates subjected for species identification the most common species identified was S. epidedermidis (58.82%). S. cohinii and S. haemolyticus being the second and third most frequently encountered species. Common source of most species was pus followed by blood and urine. S. epidermidis and S. cohnii showed resistant to multiple antibiotics. The most effective antibiotic for all the species of CONS were linezolid, teicoplanin and vancomycin. So CONS isolated from clinical samples should always be considered as potentially significant pathogen. The species identification with antibiogram will be of benefit for both epidemiological and patient care purpose.