title: Risk factors for carbapenem-resistant Gram-negative bacteremia in intensive care unit patients.
abstract: OBJECTIVE
  Carbapenem-resistant (CR) Gram-negative pathogens have increased substantially. This study was performed to identify the risk factors for development of CR Gram-negative bacteremia (GNB) in intensive care unit (ICU) patients.
  
  
  METHODS
  Prospective study; risk factors for development of CR-GNB were investigated using two groups of case patients: the first group consisted of patients who acquired carbapenem susceptible (CS) GNB and the second group included patients with CR-GNB. Both case groups were compared to a shared control group defined as patients without bacteremia, hospitalized in the ICU during the same period.
  
  
  RESULTS
  Eighty-five patients with CR- and 84 patients with CS-GNB were compared to 630 control patients, without bacteremia. Presence of VAP (OR 7.59, 95 % CI 4.54-12.69, p < 0.001) and additional intravascular devices (OR 3.69, 95 % CI 2.20-6.20, p < 0.001) were independently associated with CR-GNB. Presence of VAP (OR 2.93, 95 % CI 1.74-4.93, p < 0.001), presence of additional intravascular devices (OR 2.10, 95 % CI 1.23-3.60, p = 0.007) and SOFA score on ICU admission (OR 1.11, 95 % CI 1.03-1.20, p = 0.006) were independently associated with CS-GNB. The duration of exposure to carbapenems (OR 1.079, 95 % CI 1.022-1.139, p = 0.006) and colistin (OR 1.113, 95 % CI 1.046-1.184, p = 0.001) were independent risk factors for acquisition of CR-GNB. When the source of bacteremia was other than VAP, previous administration of carbapenems was the only factor related with the development of CR-GNB (OR 1.086, 95 % CI 1.003-1.177, p = 0.042).
  
  
  CONCLUSIONS
  Among ICU patients, VAP development and the presence of additional intravascular devices were the major risk factors for CR-GNB. In the absence of VAP, prior use of carbapenems was the only factor independently related to carbapenem resistance.
authors.affiliation: First Department of Critical Care, Medical School, University of Athens, Evangelismos Hospital, 45-47 Ipsilantou Str., 106 76, Athens, Greece. chroutsi@hotmail.com
authors.forename: Christina
authors.initials: C
authors.lastname: Routsi
authors.forename: Maria
authors.initials: M
authors.lastname: Pratikaki
authors.forename: Evangelia
authors.initials: E
authors.lastname: Platsouka
authors.forename: Christina
authors.initials: C
authors.lastname: Sotiropoulou
authors.forename: Vasileios
authors.initials: V
authors.lastname: Papas
authors.forename: Theodoros
authors.initials: T
authors.lastname: Pitsiolis
authors.forename: Athanassios
authors.initials: A
authors.lastname: Tsakris
authors.forename: Serafeim
authors.initials: S
authors.lastname: Nanas
authors.forename: Charis
authors.initials: C
authors.lastname: Roussos
mesh_terms: D016470:Bacteremia / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D015780:Carbapenems / Q000494:pharmacology*; D016022:Case-Control Studies; D003428:Cross Infection / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D006115:Greece / Q000453:epidemiology; D006801:Humans; D007362:Intensive Care Units; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012307:Risk Factors; D018440:beta-Lactam Resistance
chemical_list: D015780:Carbapenems