Alterations in bacterial spectrum and increasing resistance rates in isolated microorganisms from device-associated infections in an intensive care unit of a teaching hospital in Istanbul (2004-2010)

Abstract

The aim of the present study was to determine the rate of device-associated infection (DAI) and the change in profiles and antimicrobial resistance patterns of the causative microorganisms in a medical-surgical intensive care unit (ICU), as well as to evaluate the effect of a new nationwide hospital infection control program (NHICP), which has been implemented in Turkey. In this study, 5,772 patients that were hospitalized for a total of 43,658 days acquired 1,321 DAIs, with an overall rate of 30.2% per 1,000 ICU days. Between 2004 (before the NHICP) and 2010, the incidence densities of catheter-associated urinary tract infection (CAUTI) decreased from 10.2 to 5.7 per 1,000 device-days (P < 0.0001), and central venous catheter-associated bloodstream infection (CVC-BSI) decreased from 5.3 to 2.1 per 1,000 device-days (P < 0.0001). However, ventilator-associated pneumonia increased from 27.0 to 31.5 per 1,000 device-days. Multidrug-resistant species rates increased from 5.8% to 76.6% (P < 0.0001) for Acinetobacter spp. and from 6.8% to 53.1% (P < 0.0001) for Pseudomonas aeruginosa. The extended-spectrum β-lactamase-producing Enterobacteriaceae rate increased from 23.1% to 54.2% (P = 0.01); the vancomycin-resistance rate among Enterococcus spp. increased from 0% in 2004 to 12.5% in 2010 (P = 0.0003). In conclusion, while a significant decrease was achieved in the incidences of CAUTI and CVC-BSI, the NHICP was not completely effective in our ICU. The high incidence of DAI and the increasing prevalence of multidrug-resistant microorganisms indicate that further interventions are urgently needed.