Distribution and drug resistance of 2356 strains of gram-positive cocci

OBJECTIVE To investigate the distribution and drug resistance of Gram-positive cocci isolated in the past 3 years,and to provide an optimal antimicrobial therapy.METHODS A retrospective analysis was made to investigate drug resistance of Gram-positive cocci isolated during the period of Jan 2007 to Dec 2009.RESULTS A total of 2356 Gram-positive cocci were isolated from clinical samples,the predominant pathogen was coagulase-negative Staphylococcus.The Gram-positive cocci were mainly isolated from the specimens of sputum,blood and secretion.472 strains of meticillin-resistant Staphylococcus aureus(MRSA) were detected,none of which was resistant to linezolid and vancomycin.The resistance rates to chloramphenicol and quinupristin/dalfopristin were 12.1% and 0.6%,respectively,and to rifampin was increasing greatly from 11.5% to 73.6% in the strains of MRSA.The resistance rates of Enterococcus faecalis to penicillin G and ampicillin were 17.7% and 5.2%,respectively,which were significantly lower than those of E.faecium.None of linezolid-resistant Enterococcus and vancomycin-resistant Enterococcus isolates was detected.CONCLUSION The drug resistance of Gram-positive cocci is serious.It is very important to enhance the drug resistance monitoring and rational application of antibiotics.