Epidemiologic, clinical characteristics, and risk factors for adverse outcome in multiresistant gram-negative primary bacteremia of critically ill patients

• Published in: American journal of infection control 2011-06, Vol.39 (5), p.396-400
• Main Authors: Michalopoulos, Argyris, Falagas, Matthew E, Karatza, Dimitra C, Alexandropoulou, Paraskevi, Papadakis, Emmanuel, Gregorakos, Leonidas, Chalevelakis, George, Pappas, Georgios
• Format: Article
• Language: English
• Subjects: Acinetobacter baumannii - drug effects; Acinetobacter baumannii - pathogenicity; Aged; Anti-Infective Agents - pharmacology; Bacteremia - drug therapy; Bacteremia - epidemiology; Bacteremia - microbiology; Bacteremia - mortality; Case-Control Studies; Cohort Studies; Critical Illness - mortality; Cross Infection - drug therapy; Cross Infection - microbiology; Cross Infection - mortality; Diabetes; Diabetes Mellitus - microbiology; Drug resistance; Drug Resistance, Multiple, Bacterial; Epidemiology; Female; gram-negative bacteremia; Gram-negative bacteria; Greece - epidemiology; Humans; ICU-acquired infection; Infection Control; Infectious Disease; Intensive care; intensive care unit-acquired infection; Intensive Care Units - statistics & numerical data; Klebsiella pneumoniae - drug effects; Klebsiella pneumoniae - pathogenicity; Male; Middle Aged; Mortality; multiple drug resistance; Nosocomial infections; Primary bacteremia; Pseudomonas aeruginosa - drug effects; Pseudomonas aeruginosa - pathogenicity; Retrospective Studies; Risk Factors
• ISSN: 0196-6553; 1527-3296
• DOI: 10.1016/j.ajic.2010.06.017

Background Characteristics and burden of primary bacteremia because of multidrug-resistant (MDR) gram-negative bacteria (GNB) in intensive care unit (ICU) patients remain understudied. Methods A cohort study of patients with primary MDR GNB-related bacteremia from the ICU of a tertiary Greek hospital during a 3-year period was conducted for recognition of clinical characteristics and risk factors for adverse outcome. A case-control study was further performed to evaluate risk factors for development of MDR GNB-related primary bacteremia. Results Fifty monomicrobial episodes of primary bacteremia because of Klebsiella pneumoniae (n = 20), Acinetobacter baumannii (n = 18), and Pseudomonas aeruginosa (n = 12) were recorded. The presence of diabetes mellitus was the only significant risk factor for development of MDR GNB-related primary bacteremia. Most episodes (78%) were ICU acquired in patients with prolonged mechanical ventilation and previous hospitalization in the ward. Mortality was 47.6% vs 19% of controls, P = .01. Mortality was higher in recurrent bacteremia (62.5%). Mortality was statistically associated with age ( P = .002) and degree of multiorgan dysfunction expressed by sequential organ failure assessment score on day of bacteremia documentation ( P = .001). Conclusion Critically ill patients with MDR GNB-related primary bacteremia present significant mortality mainly associated with age and multiorgan failure. A baumanii bacteremia confers significant mortality compared with the benign course of K pneumoniae in such settings. Diabetes mellitus is a risk factor for development of such episodes, which may, in part, be general ward acquired, underlining the need for expanded vigilance.