Vitek 2 id gnb and ast n255 cards

Microbiological testing of blood culture specimens was completed at the Groote Schuur Hospital NHLS microbiology laboratory using the BACTEC 9240 automated blood culture system (Becton Dickinson, Sparks, MD, USA) in 2012 and the BacT/ALERT automated blood culture system (bioMérieux Inc., Durham, NC, USA) in 2013-2014. If growth of any pathogen was detected, standard biochemical, disc diffusion, and gradient diffusion antibiotic susceptibility tests were used to evaluate Gram-positive organisms. Gram-negative organisms were identified and tested for antibiotic susceptibility after direct inoculation of the bacterial colonies into the automated Vitek 2 system (bioMérieux, Inc., France) using Vitek 2 ID-GNB and AST-N255 cards (Bamford et al., 2010) . Where necessary, repeat testing was done on bacterial colonies subcultured onto agar plates, using Vitek 2, disc diffusion, or gradient diffusion Etest methods (bioMérieux, Marcy l'Etoile, France). Fungal isolates identified on Gram stain were inoculated onto Sabouraud dextrose agar. Identification and susceptibility testing of fungi were conducted using the Vitek 2 system with YST identification and AST-YS07 cards. Susceptibility results were interpreted according to the Clinical and Laboratory Standards Institute criteria for 2012 -2014 (CLSI, 2012 , 2013 , 2014)) .