Joyanes, PConejo, M del CarmenMartínez-Martínez, LPerea, E J2017-06-022017-06-022001-09Joyanes P, Conejo MC, Martínez-Martínez L, Perea EJ. Evaluation of the VITEK 2 system for the identification and susceptibility testing of three species of nonfermenting gram-negative rods frequently isolated from clinical samples. J Clin Microbiol. 2001;39(9):3247-53.0095-1137http://hdl.handle.net/10668/2695VITEK 2 is a new automatic system for the identification and susceptibility testing of the most clinically important bacteria. In the present study 198 clinical isolates, including Pseudomonas aeruginosa (n = 146), Acinetobacter baumannii (n = 25), and Stenotrophomonas maltophilia (n = 27) were evaluated. Reference susceptibility testing of cefepime, cefotaxime, ceftazidime, ciprofloxacin, gentamicin, imipenem, meropenem, piperacillin, tobramycin, levofloxacin (only for P. aeruginosa), co-trimoxazole (only for S. maltophilia), and ampicillin-sulbactam and tetracycline (only for A. baumannii) was performed by microdilution (NCCLS guidelines). The VITEK 2 system correctly identified 91.6, 100, and 76% of P. aeruginosa, S. maltophilia, and A. baumannii isolates, respectively, within 3 h. The respective percentages of essential agreement (to within 1 twofold dilution) for P. aeruginosa and A. baumannii were 89.0 and 88.0% (cefepime), 91.1 and 100% (cefotaxime), 95.2 and 96.0% (ceftazidime), 98.6 and 100% (ciprofloxacin), 88.4 and 100% (gentamicin), 87.0 and 92.0% (imipenem), 85.0 and 88.0% (meropenem), 84.2 and 96.0% (piperacillin), and 97.3 and 80% (tobramycin). The essential agreement for levofloxacin against P. aeruginosa was 86.3%. The percentages of essential agreement for ampicillin-sulbactam and tetracycline against A. baumannii were 88.0 and 100%, respectively. Very major errors for P. aeruginosa (resistant by the reference method, susceptible with the VITEK 2 system [resistant to susceptible]) were noted for cefepime (0.7%), cefotaxime (0.7%), gentamicin (0.7%), imipenem (1.4%), levofloxacin (2.7%), and piperacillin (2.7%) and, for one strain of A. baumannii, for imipenem. Major errors (susceptible to resistant) were noted only for P. aeruginosa and cefepime (2.0%), ceftazidime (0.7%), and piperacillin (3.4%). Minor errors ranged from 0.0% for piperacillin to 22.6% for cefotaxime against P. aeruginosa and from 0.0% for piperacillin and ciprofloxacin to 20.0% for cefepime against A. baumannii. The VITEK 2 system provided co-trimoxazole MICs only for S. maltophilia; no very major or major errors were obtained for co-trimoxazole against this species. It is concluded that the VITEK 2 system allows the rapid identification of S. maltophilia and most P. aeruginosa and A. baumannii isolates. The VITEK 2 system can perform reliable susceptibility testing of many of the antimicrobial agents used against P. aeruginosa and A. baumannii. It would be desirable if new versions of the VITEK 2 software were able to determine MICs and the corresponding clinical categories of agents active against S. maltophilia.enAcinetobacterAntibacterianosTécnicas de tipificación bacterianaInfecciones por bacterias gramnegativasPruebas de sensibilidad microbianaMedical Subject Headings::Organisms::Bacteria::Gram-Negative Bacteria::Gram-Negative Aerobic Bacteria::Gram-Negative Aerobic Rods and Cocci::Moraxellaceae::AcinetobacterMedical Subject Headings::Chemicals and Drugs::Chemical Actions and Uses::Pharmacologic Actions::Therapeutic Uses::Anti-Infective Agents::Anti-Bacterial AgentsMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Diagnostic Techniques and Procedures::Clinical Laboratory Techniques::Microbiological Techniques::Bacteriological Techniques::Bacterial Typing TechniquesMedical Subject Headings::Organisms::Bacteria::Gram-Negative Bacteria::Gram-Negative Aerobic Bacteria::Gram-Negative Aerobic Rods and CocciMedical Subject Headings::Diseases::Bacterial Infections and Mycoses::Bacterial Infections::Gram-Negative Bacterial InfectionsMedical Subject Headings::Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Primates::Haplorhini::Catarrhini::Hominidae::HumansMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Diagnostic Techniques and Procedures::Clinical Laboratory Techniques::Microbiological Techniques::Microbial Sensitivity TestsMedical Subject Headings::Organisms::Bacteria::Gram-Negative Bacteria::Gram-Negative Aerobic Bacteria::Gram-Negative Aerobic Rods and Cocci::Pseudomonadaceae::Pseudomonas::Pseudomonas aeruginosaMedical Subject Headings::Chemicals and Drugs::Chemical Actions and Uses::Pharmacologic Actions::Diagnostic Uses of Chemicals::Reagent Kits, DiagnosticMedical Subject Headings::Organisms::Bacteria::Gram-Negative Bacteria::Gram-Negative Aerobic Bacteria::Gram-Negative Aerobic Rods and Cocci::Xanthomonadaceae::Stenotrophomonas::Stenotrophomonas maltophiliaMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Diagnostic Techniques and Procedures::Clinical Laboratory Techniques::Microbiological Techniques::Bacteriological Techniquesresearch article11526158open access10.1128/JCM.39.9.3247–3253.20011098-660XPMC88326