697. Characterization of ESBL-producing Escherichia coli Associated with Combat Casualties from Iraq and Afghanistan
Session: Poster Abstract Session: Skin, Soft Tissue and Joint Infections
Friday, October 21, 2011
Room: Poster Hall B1
Background: Epidemiological shift of bacteria complicating the care of our wounded warriors from Iraq and Afghanistan has transitioned to more extended-spectrum beta-lactamase (ESBL)-producing bacteria including Escherichia coli over the last few years. The majority of the data to date implicating the role of nosocomial transmission of multidrug-resistant bacteria pertains to Acinetobacter. We describe ESBL-producing E. coli isolates collected from Iraq and the US for genotypic similarities by pulsed-field gel electrophoresis (PFGE).

Methods: We characterized ESBL-producing E. coli isolates recovered from patients at a combat support hospital (CSH) in Iraq, patients at a US military treatment facility (MTF) who had been evacuated from Iraq or Afghanistan, and isolates recovered from the same US MTF from patients not deployed between 2007 and 2010. PFGE was implemented using the Xba I restriction enzyme using commercial software (BioNumerics, Applied Maths Inc) to evaluate relatedness defined by 85% similarity.

Results:  There were a wide variety of pulsed-field types (PFTs) among the various patient populations. Only 12 of the 125 PFTs were associated with more than 1 patient population. None of the 6 isolates with the same PFTs from Iraq and the US MTF populations were recovered within 30 days of each other. Two PFTs (of 7) described from the single US MTF two populations were recovered within a 30 day period (same day and 6 days).

 

Patients

Isolates

Isolate Source

PFTs

 

 

 

Survey

Wound

Blood

Urine

Other

 

CSH Iraq*

37

55

0

14

1

11

11

45

US MTF, deployed

31

64

45

7

4

3

5

35

US MTF, non-deployed

62

104

6

16

1

70

11

45

*sources for only 37 isolates available

From the same populations, non-ESBL-producing E. coli included 91 isolates (74 PFTs) from the CSH, 96 isolates (82 patients, 66 PFTs) from the US MTF, non-deployed, and 70 isolates (58 patients, 49 PFTs) from the US MTF, deployed. 16 ESBL- and non-ESBL-producing E. coli clones overlapped between the various populations of which 4 had isolates recovered within 30 days of each other (2 between Iraq and US MTF patient populations).

Conclusion: There does not appear to be strain clonality associated with isolates infecting our wounded warriors and limited data implicating nosocomial transmission of pathogens.


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

Clinton K. Murray, MD1, Wade Aldous, PhD1, Edward Keen, PhD1, Bradley Lloyd, MD2, Stephanie Schmitz, PhD2, Charles Guymon, MA3, Miriam Beckius, MPH1, Wendy Zera, BS4, Xin Yu1, Kristelle Cheatle, BA1, Katrin Mende, PhD5, David Tribble, MD, DrPH6 and Duane Hospenthal, MD, PhD7, (1)San Antonio Military Medical Center, Fort Sam Houston, TX, (2)Landstuhl Regional Medical Center, Landstuhl, Germany, (3)US Army Institute of Surgical Research, Fort Sam Houston, TX, (4)Infectious Disease Clinical Research Program, Fort Sam Houston, TX, (5)Infectious Disease Clinical Research Program, Uniformed Services University, Bethesda, MD, (6)IDCRP/Uniformed Services Univ. of the Hlth. Sci., Bethesda, MD, (7)San Antonio Military Medical Center, MCHE MDI 7 East, TX

Disclosures:

C. K. Murray, None

W. Aldous, None

E. Keen, None

B. Lloyd, None

S. Schmitz, None

C. Guymon, None

M. Beckius, None

W. Zera, None

X. Yu, None

K. Cheatle, None

K. Mende, None

D. Tribble, None

D. Hospenthal, None

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