Microbiological characteristics of catheter-related bacteremia in a Tunisian intensive care unit

Prevalence of catheter-related bacteremia in intensive care units is increasing as central venous catheters (CVC) are used more frequently. In the most of the published literature, Gram positive cocci are the leading cause of catheter-related bacteremia and the systemic empiric treatment recommended include the administration of glycopeptides.

To search for the microbiological characteristics of catheter-related bacteremia in a Tunisian ICU.

Prospective observational cohort survey conducted in the ICU of the Habib Bourguiba university hospital, Tunisia (a 22 bed medical-surgical intensive care unit). We had included all patients admitted to the unit over the study period (from August 1st, 2001 to March 31st, 2002), and who submitted to a central venous catheter for more than 24 hours. Catheter-tip specimens were cultured using a semiquantitative method.

During the study period 218 central venous catheters (CVC) were assessed. The mean length of time the catheter was kept in place was 8±6.7 days (range; 2 and 46 days). The CVC insertion site was the subclavian vein in 156 cases (71.6%), the jugular vein in 35 cases (16%), and the femoral vein in 27 cases (12.4%). Seventy four catheters (33.9%) were removed because of suspicion of catheter-related sepsis. The catheter-related bacteremia rate was 6.1 infections/1000 days-CVC. Unlike Gram-positive cocci which caused only one case of catheter-related bacteremia, Gram-negative rods, namely Klebsiella pneumoniae and Serratia marcescens were responsible for 91.7% of cases of catheter-related bacteremia.

Our findings translate a specific microbiological flora in our Tunisian intensive care unit and highlight the importance of a treatment strategy based on local epidemiology in patients with catheter related bacteremia.