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Colonization Status and Appropriate Antibiotic Therapy for Nosocomial Bacteremia Caused by Antibiotic-Resistant Gram-Negative Bacteria in an Intensive Care Unit

  • Stijn Blot (a1), Pieter Depuydt (a1), Dirk Vogelaers (a2), Johan Decruyenaere (a1), Jan De Waele (a1), Eric Hoste (a1), Renaat Peleman (a2), Geert Claeys (a3), Gerda Verschraegen (a3), Francis Colardyn (a1) and Koenraad Vandewoude (a1)...

Timely initiation of antibiotic therapy is crucial for severe infection. Appropriate antibiotic therapy is often delayed for nosocomial infections caused by antibiotic-resistant bacteria. The relationship between knowledge of colonization caused by antibiotic-resistant gram-negative bacteria (ABR-GNB) and rate of appropriate initial antibiotic therapy for subsequent bacteremia was evaluated.


Retrospective cohort study.


Fifty-four-bed intensive care unit (ICU) of a university hospital. In this unit, colonization surveillance is performed through routine site-specific surveillance cultures (urine, mouth, trachea, and anus). Additional cultures are performed when presumed clinically relevant.


ICU patients with nosocomial bacteremia caused by ABR-GNB.


Infectious and microbiological characteristics and rates of appropriate antibiotic therapy were compared between patients with and without colonization prior to bacteremia. Prior colonization was defined as the presence (detected ≥ 2 days before the onset of bacteremia) of the same ABR-GNB in colonization and subsequent blood cultures. During the study period, 157 episodes of bacteremia caused by ABR-GNB were suitable for evaluation. One hundred seventeen episodes of bacteremia (74.5%) were preceded by colonization. Appropriate empiric antibiotic therapy (started within 24 hours) was administered for 74.4% of these episodes versus 55.0% of the episodes that occurred without prior colonization. Appropriate therapy was administered within 48 hours for all episodes preceded by colonization versus 90.0% of episodes without prior colonization.


Knowledge of colonization status prior to infection is associated with higher rates of appropriate therapy for patients with bacteremia caused by ABR-GNB (Infect Control Hosp Epidemiol 2005;26:575-579).

Corresponding author
Ghent University Hospital, Intensive Care Dept., De Pintelaan 185, B-9000 Gent,
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Infection Control & Hospital Epidemiology
  • ISSN: 0899-823X
  • EISSN: 1559-6834
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