title: Comparison of culture media for detection of Acinetobacter baumannii in surveillance cultures of critically-ill patients.
abstract: The objective of this study was to evaluate the performance of CHROMagar Acinetobacter when compared to sheep blood agar, MacConkey agar and MacConkey agar with 6 μg/ml of imipenem for the detection of A. baumannii in surveillance cultures of hospitalized patients. We utilized peri-anal swabs and sputum samples from patients admitted to the University of Maryland Medical Center ICUs from December 7 through December 21, 2009. Samples were plated onto four media in the following order: (1) 5% sheep blood agar (SBA), (2) MacConkey agar, (3) MacConkey agar with 6 μg/ml of imipenem, and (4) CHROMagar Acinetobacter (CHROMagar). SBA was the gold standard to which all media was compared. There were 165 samples collected during the study period. SBA and CHROMagar detected 18 of 18 (100%) Acinetobacter and 11 of 11 (100%) MDR-A. baumannii. MacConkey agar detected 16 of 18 (89%) Acinetobacter and 10 of 11 (91%) MDR- A. baumannii while MacConkey agar with 6 μg/ml imipenem detected 9 of 11 (82%) MDR-A. baumannii. CHROMagar did not differentiate MDR- A. baumannii from non-MDR-A. baumannii. CHROMagar may be useful for rapid detection of patients with MDR-A. baumannii if improved upon to better select for MDR-A. baumannii.
authors.affiliation: Department of Epidemiology and Public Health, University of Maryland School of Medicine, 685 W. Baltimore St, Baltimore, MD 21201, USA. aajao@epi.umaryland.edu
authors.forename: A O
authors.initials: AO
authors.lastname: Ajao
authors.forename: G
authors.initials: G
authors.lastname: Robinson
authors.forename: M S
authors.initials: MS
authors.lastname: Lee
authors.forename: T D
authors.initials: TD
authors.lastname: Ranke
authors.forename: R A
authors.initials: RA
authors.lastname: Venezia
authors.forename: J P
authors.initials: JP
authors.lastname: Furuno
authors.forename: A D
authors.initials: AD
authors.lastname: Harris
authors.forename: J K
authors.initials: JK
authors.lastname: Johnson
mesh_terms: D000151:Acinetobacter Infections / Q000175:diagnosis / Q000382:microbiology*; D040981:Acinetobacter baumannii / Q000187:drug effects / Q000302:isolation & purification*; D001003:Anal Canal / Q000382:microbiology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001431:Bacteriological Techniques / Q000379:methods*; D015331:Cohort Studies; D016638:Critical Illness; D003470:Culture Media / Q000737:chemistry*; D024901:Drug Resistance, Multiple, Bacterial; D006801:Humans; D015378:Imipenem / Q000494:pharmacology; D017053:Infection Control; D007362:Intensive Care Units; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D003470:Culture Media; D015378:Imipenem