Ann Lab Med.  2013 Jul;33(4):279-282. 10.3343/alm.2013.33.4.279.

Nosocomial Infection by Sequence Type 357 Multidrug-Resistant Acinetobacter baumannii Isolates in a Neonatal Intensive Care Unit in Daejeon, Korea

• Sung JY
• Koo SH
• Cho HH
• Kwon KC

• KMID: 1707236
• DOI: http://doi.org/10.3343/alm.2013.33.4.279

Abstract

Acinetobacter baumannii is an important microorganism responsible for a number of nosocomial outbreaks, in particular, in intensive care units (ICUs). We investigated a nosocomial infection caused by multidrug-resistant (MDR) A. baumannii in a neonatal intensive care unit (NICU) in Korea. A. baumannii isolates were characterized using Etest (AB Biodisk, Sweden), two multiplex PCR assays, and multilocus sequence typing (MLST) scheme. PCR and PCR mapping experiments were performed for detecting and characterizing the determinants of antimicrobial resistance. Eight strains isolated from an NICU belonged to European (EU) clone II and revealed only one sequence type (ST), namely, ST357. All the isolates were susceptible to imipenem but were resistant to amikacin, gentamicin, ceftazidime, cefepime, and ciprofloxacin. To the best of our knowledge, this is the first report of a nosocomial infection in an NICU in Korea caused by ST357 MDR/carbapenem-susceptible A. baumannii strains. This result demonstrates that nosocomial outbreaks of MDR/carbapenem-susceptible strains as well as MDR/carbapenem-resistant isolates may occur in NICUs.

Keyword

Acinetobacter baumannii; Neonatal intensive care unit; Nosocomial infection; Carbapenem

MeSH Terms

Acinetobacter Infections/diagnosis/*microbiology
Acinetobacter baumannii/drug effects/genetics/*isolation & purification/metabolism
Anti-Bacterial Agents/pharmacology
Bacterial Proteins/genetics
Cross Infection/*microbiology
DNA, Bacterial/analysis
*Drug Resistance, Multiple, Bacterial
Humans
Imipenem/pharmacology
Infant, Newborn
*Intensive Care Units, Neonatal
Microbial Sensitivity Tests
Multilocus Sequence Typing
Multiplex Polymerase Chain Reaction
Republic of Korea
Anti-Bacterial Agents
Bacterial Proteins
DNA, Bacterial
Imipenem

Figure

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  Fig. 1 Repetitive element sequence-based (REP)-PCR patterns of multidrug-resistant A. baumannii strains. Lane M, 1-kb DNA size marker; Lanes 1, 2, 3, 4, 5, 6, 7, and 8, isolates C10, C51, C64, C81, C84, C85, C132, and C147, respectively.

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