title: Epidemiology and clonality of carbapenem-resistant Acinetobacter baumannii from an intensive care unit in Palermo, Italy.
abstract: BACKGROUND
  Multidrug-resistant Acinetobacter baumannii, initially considered as having a poor clinical relevance, is frequently isolated from infection cases in intensive care units. We describe the epidemiology of carbapenem resistant A. baumannii (CRAB) in a general ICU in Palermo, Italy, from October 2010 to March 2011.
  
  
  RESULTS
  58 of 61 isolates exhibited MICs for meropenem or imipenem ≥16 mg/L. Forty-nine carried blaOXA-23 and two blaOXA-58 genes.Five subtype clusters were detected by rep-PCR. Clusters D and E included 10 isolates that tested negative for the carbapenem resistance genes. MLST attributed all isolates, but two, with sequence type (ST)2, whereas the two remaining isolates with ST78.The respiratory tract was the most common site of infection (26 out of 36 cases. 72.2%). A high infection related mortality rate was observed (18 out of 35 patients, 51.4%). Nineteen patients tested positive for other multidrug resistant organisms in addition to CRAB. In eight cases isolates belonging to distinct subtype clusters and/or with distinct carbapenemase profiles were identified.
  
  
  CONCLUSIONS
  Carbapenem resistance was prominently driven by the dissemination of CRAB isolates belonging to ST2, carrying the carbapenemase gene blaOXA-23. The colonization/infection of some patients by multiple strains is suggestive of an endemic circulation of CRAB.
authors: Department of Sciences for Health Promotion G, D'Alessandro, Section of Hygiene, University of Palermo, Palermo, Italy. caterina.mammina@unipa.it
authors: Caterina
authors: C
authors: Mammina
authors: Daniela Maria
authors: DM
authors: Palma
authors: Celestino
authors: C
authors: Bonura
authors: Aurora
authors: A
authors: Aleo
authors: Teresa
authors: T
authors: Fasciana
authors: Concetta
authors: C
authors: Sodano
authors: Maria Antonietta
authors: MA
authors: Saporito
authors: Maria Stella
authors: MS
authors: Verde
authors: Cinzia
authors: C
authors: Calà
authors: Andrea Neville
authors: AN
authors: Cracchiolo
authors: Romano
authors: R
authors: Tetamo
mesh_terms: D000151:Acinetobacter Infections / Q000453:epidemiology* / Q000382:microbiology*; D040981:Acinetobacter baumannii / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015780:Carbapenems / Q000494:pharmacology*; D002999:Clone Cells; D003710:Demography; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects*; D005260:Female; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D007558:Italy / Q000453:epidemiology; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D013997:Time Factors; D055815:Young Adult
chemical_list: D015780:Carbapenems