519. Risk Factors for Extended Spectrum ?-Lactamase Escherichia coli Versus Susceptible E. coli in Surgical-site Infections among Cancer Patients in Mexico
Session: Poster Abstract Session: Surgical Site Infections
Thursday, October 3, 2013
Room: The Moscone Center: Poster Hall C
  • 519_IDWPoster.pdf (810.4 kB)
  • Background: Extended-spectrum β-lactamase (ESBL) Escherichia coli are of increasing concern as a cause of healthcare-associated infections. The purpose of this study was to identify the incidence and risk factors for surgical site infections (SSI) caused by ESBL E. coli among patients in Instituto Nacional de Cancerología in Mexico City.

    Methods: Between 2008 and 2012, 269 ESBL E. coli infections/episodes of 16,519 surgeries (1.6%) were identified. Using a matched case-control design, demographics, antibiotic use and relevant surgical data were obtained for 173 cases (ESBL E. coli SSI) and 173 controls (antibiotic-susceptible E. coli SSI).  Conditional logistic regression modeling was used to calculate odds ratios.

    Results: Mean age of patients was 53.6 years, 214 (62%) were female. Demographics and comorbidities were similar between the groups (p= NS). Patients undergoing gastrointestinal surgery were significantly more likely to have an ESBL even though duration of surgery was not significantly different between cases and controls. Although prophylaxis was common among cases and controls (84% and 89%), more than half of cases (53%) were given prophylaxis outside of the recommended application window or were exposed for over 24 hours in comparison to 29% of controls. In addition, exposure to antibiotics during the post-operative period but prior to SSI diagnosis was observed more frequently among cases than controls. Among patients using antibiotics after surgery, cephalosporins were used in 86% of cases versus 73% of controls. Post-surgery cephalosporin use (OR= 3.26, 95%CI= 1.80-5.92) and inappropriate prophylaxis (OR= 2.38, 95%CI= 1.30-4.36) were associated with ESBL E. coli SSIs.

    Conclusion: Reduced exposure to cephalosporins and the appropriate timing and duration of perioperative antimicrobial prophylaxis were associated with lower risk of ESBL E. coli in SSIs.  Compliance to antimicrobial prophylaxis guidelines is of utmost importance.

    Claudia Montes, Columbia Mailman School of Public Health, New York, NY, Elaine Larson, PhD, RN, FIDSA, FSHEA, School of Nursing, Columbia University Medical Center, New York, NY, Bertha Garcia Pineda, RN, Departement of Infectious Diseases, Instituto Nacional De Cancerologia, Mexico City, Mexico, Consuelo Velaquez, Microbiology Laboratory, Instituto Nacional De Cancerologia, Mexico City, Mexico and Diana Vilar-Compte, MD, MsC, Instituto Nacional De Cancerologia, Mexico City, Mexico


    C. Montes, None

    E. Larson, None

    B. Garcia Pineda, None

    C. Velaquez, None

    D. Vilar-Compte, None

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