Ann Lab Med.  2013 May;33(3):193-195. 10.3343/alm.2013.33.3.193.

Modified CHROMagar Acinetobacter Medium for Direct Detection of Multidrug-Resistant Acinetobacter Strains in Nasal and Rectal Swab Samples

• Song W
• Lee J
• Kim TK
• Park MJ
• Kim HS
• Kim JS

• KMID: 1781325
• DOI: http://doi.org/10.3343/alm.2013.33.3.193

Abstract

This study aimed to investigate whether CHROMagar Acinetobacter medium (CHROMagar, France) in combination with an antimicrobial supplement (modified CHROMagar Acinetobacter; CHROMagar, France) can be used for detecting and isolating multidrug-resistant Acinetobacter species (MRA) in nasal and rectal surveillance cultures. Nasal and rectal swab samples were collected from patients in an intensive care unit at a teaching hospital. The samples were used to inoculate modified CHROMagar Acinetobacter plates, which were examined after 24 and 48 hr of incubation at 37degrees C. Their susceptibility against the antimicrobial agents meropenem, imipenem, ciprofloxacin, and amikacin was analyzed using the Etest (bioMerieux, France). A total of 406 paired samples (406 nasal swabs and 406 rectal swabs) were obtained from 226 patients, and 120 samples (28 nasal and 28 rectal cultures, 47 nasal cultures only, and 17 rectal cultures only) yielded MRA. Seventy-five MRA isolates (18.5%) were recovered from the 406 nasal samples, and 45 MRA isolates (11.1%) were recovered from the 406 rectal samples. Of the 120 MRA isolates, 3 (2.5%) were detected only after 48 hr of incubation. The use of modified CHROMagar Acinetobacter together with nasal and rectal swabs and 1-day incubation is an effective surveillance tool for detecting MRA colonization.

Keyword

Modified CHROMagar Acinetobacter; Multidrug-resistant Acinetobacter spp.; Nasal swab; Rectal swab

MeSH Terms

Acinetobacter/drug effects/*isolation & purification
Acinetobacter Infections/diagnosis/microbiology
Anti-Bacterial Agents/pharmacology
*Drug Resistance, Multiple, Bacterial/drug effects
Humans
Intensive Care Units
Microbial Sensitivity Tests
Nose/*microbiology
Reagent Kits, Diagnostic
Rectum/*microbiology
Anti-Bacterial Agents
Reagent Kits, Diagnostic

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