caa a22 4500 397592582 CHVBK 20180308164943.0 cr unu---uuuuu 161202e199603 xx s 000 0 eng 10.1093/jac/37.3.445 doi (NATIONALLICENCE)oxford-10.1093/jac/37.3.445 Identification of mecA-related oxacillin resistance in staphylococci by the E test and the broth microdilution method [Elektronische Daten] [A. C. Petersson, H. Miörner, C. Kamme] A set of 165 strains of different staphylococcal species, 67 Staphylococcus aureus 71 novobiocin-sensitive coagulase-negative staphylococci (CNS) and 27 novobiocin-re-sistant CNS was used. The oxacillin and methicillin MICs were recorded after 24 and 42 h of incubation at 35°C and at 30°C. Significantly higher MICs were recorded at 30°C compared with 35°C. While a poor discrimination between mecA-positive and mecA-negative strains was obtained with methicillin, the oxacillin MICs enabled identification of resistant strains under certain conditions. The distribution of MICs differed between the three groups of species. Separation of uninduced mecA-positive (≥4.0 mg oxacillin/L) and mecA-negative (≤2.0 mg oxacillin/L) strains of S. aureus was only achieved with the E test and after 42 h of incubation. Oxacillin-induction yielded higher MICs for mecA-positive strains of S. aureus, and a separation from mecA-negative strains was achieved with the E test after 24 h and with the broth microdilution method after 42 h. Separation of mecA-positive and mecA-negative strains of novobiocin-sensitive CNS required agar supplemented with 5/ blood, incubation of MIC trays and E test for 42 h, and species-specific oxacillin MIC breakpoints (S≤0.5mg/L and R≥1.0mg/L). The mecA-positive and mecA-negative strains of novobiocin-resistant CNS were clearly separated after 24 h of incubation by either method. © 1996 The British Society for Antimicrobial Chemotherapy Original articles nationallicence Petersson A. C. Clinical Microbiology Laboratory, University Hospital of Lund, Sölvegatan 23, S-223 62 Lund, Sweden aut Miörner H. Clinical Microbiology Laboratory, University Hospital of Lund, Sölvegatan 23, S-223 62 Lund, Sweden aut Kamme C. Clinical Microbiology Laboratory, University Hospital of Lund, Sölvegatan 23, S-223 62 Lund, Sweden aut Journal of Antimicrobial Chemotherapy Oxford University Press 37/3(1996-03), 445-456 0305-7453 37:3<445 1996 37 jac https://doi.org/10.1093/jac/37.3.445 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/jac/37.3.445 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Petersson A. C. Clinical Microbiology Laboratory, University Hospital of Lund, Sölvegatan 23, S-223 62 Lund, Sweden aut NATIONALLICENCE 700 1- Miörner H. Clinical Microbiology Laboratory, University Hospital of Lund, Sölvegatan 23, S-223 62 Lund, Sweden aut NATIONALLICENCE 700 1- Kamme C. Clinical Microbiology Laboratory, University Hospital of Lund, Sölvegatan 23, S-223 62 Lund, Sweden aut NATIONALLICENCE 773 0- Journal of Antimicrobial Chemotherapy Oxford University Press 37/3(1996-03), 445-456 0305-7453 37:3<445 1996 37 jac Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford