Evaluation of the Cobas-Bact system for direct and rapid identification and antimicrobial susceptibility testing of gram-negative rods from positive blood culture broths. 1989

W Kamm, and A Wenger, and J Bille
Institut de Microbiologie, Université de Lausanne, Centre Hospitalier Universitaire, Vaudois, Switzerland.

A direct antimicrobial susceptibility test and a direct identification of positive blood culture broths for gram-negative rods confirmed with Gram stain by using a new instrument, Cobas-Bact, were compared with the conventional Kirby-Bauer agar diffusion disk method and with the in-house set of identification or API 20E, respectively. The bacterial pellet of centrifuged positive blood culture broth was used to inoculate a Cobas-Bact susceptibility and identification rotor. Bacteria from 206 cases of monomicrobial septicemia due to members of the family Enterobacteriaceae were tested. In 198 episodes (96%), direct identification and antimicrobial susceptibility testing results were obtained for the same bacterial pathogen within 5 h of detection. Of 204 direct identifications obtained, 177 (86.6%) were "high-confidence" correct identifications (percentage of likelihood [P] greater than or equal to 80%) and 25 (12.5%) "low-confidence" correct identifications (P less than 80%), whereas only 2 misidentifications occurred (1 Escherichia coli and 1 Proteus mirabilis). Direct susceptibility testing was performed in 199 episodes (96%), providing 1,885 antibiotic-microorganism combinations. Full agreement reached 86.3%, and essential agreement reached 92.8%. Minor discrepancies were found in 120 (6.5%) of the tests, major discrepancies were found in 127 (6.8%) tests, and very major discrepancies were found in only 7 (0.4%) tests. Subsequent MIC determinations in cases of major or very major discrepancies reduced the number of major discrepancies involving cephalosporins from 60 to 16, whereas all those involving aminoglycosides remained. Overall, this direct and rapid Cobas-Bact identification and susceptibility testing procedure offered accurate information with 5 to 6 h after the laboratory detection of bacteremia and septicemia due to members of the Enterobacteriacease.

UI MeSH Term Description Entries
D008826 Microbial Sensitivity Tests Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses). Bacterial Sensitivity Tests,Drug Sensitivity Assay, Microbial,Minimum Inhibitory Concentration,Antibacterial Susceptibility Breakpoint Determination,Antibiogram,Antimicrobial Susceptibility Breakpoint Determination,Bacterial Sensitivity Test,Breakpoint Determination, Antibacterial Susceptibility,Breakpoint Determination, Antimicrobial Susceptibility,Fungal Drug Sensitivity Tests,Fungus Drug Sensitivity Tests,Sensitivity Test, Bacterial,Sensitivity Tests, Bacterial,Test, Bacterial Sensitivity,Tests, Bacterial Sensitivity,Viral Drug Sensitivity Tests,Virus Drug Sensitivity Tests,Antibiograms,Concentration, Minimum Inhibitory,Concentrations, Minimum Inhibitory,Inhibitory Concentration, Minimum,Inhibitory Concentrations, Minimum,Microbial Sensitivity Test,Minimum Inhibitory Concentrations,Sensitivity Test, Microbial,Sensitivity Tests, Microbial,Test, Microbial Sensitivity,Tests, Microbial Sensitivity
D004755 Enterobacteriaceae A family of gram-negative, facultatively anaerobic, rod-shaped bacteria that do not form endospores. Its organisms are distributed worldwide with some being saprophytes and others being plant and animal parasites. Many species are of considerable economic importance due to their pathogenic effects on agriculture and livestock. Coliform Bacilli,Enterobacteria,Ewingella,Leclercia,Paracolobactrum,Sodalis
D004756 Enterobacteriaceae Infections Infections with bacteria of the family ENTEROBACTERIACEAE. Enterobacterial Infections,Cronobacter Infections,Infections, Enterobacteriaceae,Infections, Enterobacterial,Cronobacter Infection,Enterobacteriaceae Infection,Enterobacterial Infection,Infection, Cronobacter,Infection, Enterobacteriaceae,Infection, Enterobacterial,Infections, Cronobacter
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001431 Bacteriological Techniques Techniques used in studying bacteria. Bacteriologic Technic,Bacteriologic Technics,Bacteriologic Techniques,Bacteriological Technique,Technic, Bacteriological,Technics, Bacteriological,Technique, Bacteriological,Techniques, Bacteriological,Bacteriologic Technique,Bacteriological Technic,Bacteriological Technics,Technic, Bacteriologic,Technics, Bacteriologic,Technique, Bacteriologic,Techniques, Bacteriologic
D018805 Sepsis Systemic inflammatory response syndrome with a proven or suspected infectious etiology. When sepsis is associated with organ dysfunction distant from the site of infection, it is called severe sepsis. When sepsis is accompanied by HYPOTENSION despite adequate fluid infusion, it is called SEPTIC SHOCK. Bloodstream Infection,Pyaemia,Pyemia,Pyohemia,Blood Poisoning,Poisoning, Blood,Septicemia,Severe Sepsis,Blood Poisonings,Bloodstream Infections,Infection, Bloodstream,Poisonings, Blood,Pyaemias,Pyemias,Pyohemias,Sepsis, Severe,Septicemias

Related Publications

W Kamm, and A Wenger, and J Bille
September 2002, European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology,
W Kamm, and A Wenger, and J Bille
December 1985, European journal of clinical microbiology,
W Kamm, and A Wenger, and J Bille
May 2012, European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology,
Copied contents to your clipboard!