387. Gram-Negative Multidrug Resistant Organism Colonization at Admission to U.S. Military Hospitals
Session: Poster Abstract Session: Gram Negative Infection - Epidemiology and Prevention
Friday, October 21, 2011
Room: Poster Hall B1
Background: Infections with gram-negative multidrug resistant organisms (GN MDROs) have increased in US military hospitals since the start of operations in Iraq and Afghanistan. Standardized infection control policy employs active surveillance for colonization (ASC) focusing on GN MDROs (admission groin swab cultures). We evaluated the prevalence of and risk factors for GN MDRO colonization among trauma patients injured during deployment.

Methods: Clinical data on injury circumstances, management and microbiology was collected from a de-identified trauma registry augmented by an infectious diseases module. Patient population includes injured patients transferred via Landstuhl Regional Medical Center (LRMC) in Germany to 1 of 3 US military hospitals. Chi square tests were utilized to evaluate risk factor associations.

Results: From June – November 2009, 704 patients were admitted to LRMC; 360 (51%) of these were subsequently admitted to 1 of the 3 US hospitals. ASC prevalence rates at LRMC were 7.8% [95% confidence interval (CI) 5.1, 10.5] compared to 16.9% (13.0, 20.8) at US hospitals with no difference between US sites. Isolated GN MDROs included: E. coli (64%), A. baumannii (23%), K. pneumoniae (11%), and E. gergoviae (1%). Of the 61 patients colonized at US hospitals, only 19 (31%) were also colonized at LRMC. None of the variables evaluated were significantly associated with GN MDRO colonization; however, the following showed borderline association: any antibiotic use prior to admission (p = 0.09), prior fluoroquinolone use (p = 0.08), and massive blood transfusion (p = 0.09).

Conclusion: Prevalence of GN MDRO colonization is significantly higher at the US hospitals than LRMC. Potential reasons include: different culturing techniques, different antibiotic or antiseptic use, or nosocomial acquisition from LRMC to the US. Potential risk factors for colonization identified need to be confirmed in additional patients.

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

Amy Weintrob, MD1, Ping Li, MS2, Lakisha Gaskins, MHS3, Anuradha Ganesan, MD4, Katrin Mende, PhD1, William P. Bradley, MS1, Bradley Lloyd, MD5, Susan Fraser, MD6, Tyler Warkentien, MD7, Francoise Seillier-Moiseiwitsch, PhD2, Eugene Millar, PhD1, Duane Hospenthal, MD, PhD8, Clinton K. Murray, MD9 and David Tribble, MD, DrPH2, (1)Infectious Disease Clinical Research Program, Uniformed Services University of the Health Sciences, Bethesda, MD, (2)IDCRP/Uniformed Services Univ. of the Hlth. Sci., Bethesda, MD, (3)IDCRP/Uniformed Services Univ Health Sci, Bethesda, MD, (4)Infectious Disease Clinical Research Program, Uniformed Services University, Bethesda, MD, (5)Landstuhl Regional Medical Center, Landstuhl, Germany, (6)Walter Reed Army Medical Center, Washington , DC, (7)Infectious Disease, National Naval Medical Center, Bethesda, MD, (8)Brooke Army Medical Center, Fort Sam Houston, TX, (9)Brooke Army Medical Center, Ft. Sam Houston, TX


A. Weintrob, None

P. Li, None

L. Gaskins, None

A. Ganesan, None

K. Mende, None

W. P. Bradley, None

B. Lloyd, None

S. Fraser, None

T. Warkentien, None

F. Seillier-Moiseiwitsch, None

E. Millar, None

D. Hospenthal, None

C. K. Murray, None

D. Tribble, 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.