385. Carbapenem-resistant Acinetobacter (CRA): Epidemiology and risk factors in tertiary care center
Session: Poster Abstract Session: Gram Negative Infection - Epidemiology and Prevention
Friday, October 21, 2011
Room: Poster Hall B1
  • Presentation1.pdf (125.3 kB)
  • Background:  Studies worldwide have suggested multiple risk factors, clinical characteristics and outcomes of infection with CRA. The purpose of this study was to describe our experience with these organisms in a tertiary care center.

    Methods: We performed a retrospective analysis of clinical characteristics and outcomes of patients with CRA infections from January 2009 to January 2011.  Additionally, we performed an age/sex-matched case-control study, comparing patients with carbapenem-resistant and sensitive Acinetobacter infections.

    Results: We identified 66 cases of CRA and 76 controls. Demographics, comorbidities, line days and ventilator days were similar between the two groups. Mean±SD Hospital length of stay in days was 37±27 for CRA vs. 28±28 for controls (p=0.03).   CRA cases were most frequently considered hospital-acquired (59%) and occurred in the ICU (73%). The majority of CRA species were A. baumannii (65%) and organisms were most frequently isolated from respiratory sources (52%) or blood (17%). Other significant clinical characteristics and outcomes are shown in the table. CRA cases were treated with amikacin (9%), colistin (61%), minocycline (12%), and tigecycline (24%). While there was a higher risk of relapse, there were no significant differences in microbiological persistence or all cause mortality.

    Conclusion: CRA appears to be associated with recent exposure to both acute and long term healthcare facilities, as well as a longer hospital length of stay. CRA patients were more likely to have a history of previous antibiotic use. CRA had a higher risk of relapse, but in this study it was not associated with increased all cause mortality.


    Cases (n=66)

    Controls (n=76)

    OR (95%CI)

    Any hospital admission within 3 months (%)



    5.7 (2.8-11.8)

    Any long term care facility within 3 months (%)



    3.4 (1.1-10.4)

    Antibiotic exposure within 14 days (%)



    2.9 (1.3-6.3)

    Antibiotic exposure within 30 days (%)



    3.4 (1.6-7.3)

    Antibiotic exposure within 90 days (%)



    3.2 (1.3-7.6)

    Relapse within 30 days (%)



    11.8 (1.8-73.85)

    All cause mortality (%)





    Subject Category: N. Hospital-acquired and surgical infections, infection control, and health outcomes including general public health and health services research

    Madiha Ashraf, MD1, Audrey Wanger, PhD2, Enuo Chen1 and Luis Ostrosky-Zeichner, MD, FIDSA1, (1)Division of Infectious Diseases, University of Texas Medical School at Houston, Houston, TX, (2)Department of Pathology, University of Texas Medical School at Houston, Houston, TX


    M. Ashraf, None

    A. Wanger, None

    E. Chen, None

    L. Ostrosky-Zeichner, None

    Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.