[Correlation factor analysis of pan-drug resistant Acinetobacter baumannii strains in acquired infections].
OBJECTIVE
To explore the clinical factors, drug resistance and molecular epidemiology homologous characteristics of pan-drug resistant Acinetobacter baumannii (PDRAB) in acquired infections and analyze the correlation factor between epidemic characteristics and acquired infections.


METHODS
A total of 60 PDRAB strains from nine acquired infections and related clinic data were collected from January 2009 to January 2011. The drug-resistant phenotype was tested by disk diffusion methods. The isolate identification and homology were studied by automation repetitive-element sequence-based (REP)-PCR typing platform from genes and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-TOF MS) from proteins.


RESULTS
All strains were resistant to 12 antibiotics except 2 strains to imipenem and meropenem. The strains in this study were divided into 12 types (A-L) by REP-PCR. And 60 strains were also clustered to a-e types by MALDI-TOF-TOF MS. Compared with MALDI-TOF-TOF MS, REP-PCR tended to be more accurate. Breathing machine carriage and cross transmission were the main reasons for a major epidemic outbreak at department of pulmonary medicine from July 2009 to October 2009. Hand transmission of medical care personnel was a key factor for SICU 2010 January to February. The contamination and transmission to environment of PDRAB in nasal pharynx or respiratory tract by superspreader were the main reasons for the other 7 epidemic outbreaks. Department of emergency medicine was the source of acquired infections.


CONCLUSIONS
The key control measures of acquired infections are early identification and isolation of spreader, environment and instrument disinfection, hand washing and rational uses of antibiotics. MALDI-TOF-TOF MS will become a preferred tool of identification and classification of microorganisms because of its simple operation, affordable price and handling rapidity.
Department of Clinical Laboratory Medicine, Affiliated Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
Yan-Fei
YF
Huang
Jun-Rui
JR
Wang
Hai-Tong
HT
Gu
Xin-Rong
XR
Shang
Jing-Jing
JJ
Cao
Mei
M
Wang
Yan-Yan
YY
Fan
Wen-Jun
WJ
Sui
Xin-Xin
XX
Lu
D000151:Acinetobacter Infections / Q000453:epidemiology; D040981:Acinetobacter baumannii / Q000302:isolation & purification; D000900:Anti-Bacterial Agents; D003428:Cross Infection / Q000453:epidemiology; D005163:Factor Analysis, Statistical; D006801:Humans; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D000900:Anti-Bacterial Agents