Computational and Mathematical Methods in Medicine
Volume 2012 (2012), Article ID 605861, 8 pages
Research Article

Mathematical Model of the Impact of a Nonantibiotic Treatment for Clostridium difficile on the Endemic Prevalence of Vancomycin-Resistant Enterococci in a Hospital Setting

1Cornerstone Research Group Inc., 204-3228 South Service Road, Burlington, ON, Canada L7N 3H8
2Mathematics Department, Vanderbilt University, Nashville, TN, 37240, USA
3Division of Infectious Disease, Beth Israel Deaconess Medical Center, Harvard Medical School, Lowry Building Suite 6A, 100 Francis Street, Boston, MA, 02215, USA

Received 23 June 2011; Accepted 4 October 2011

Academic Editor: Philip Crooke

Copyright © 2012 Daniel T. Grima et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Introduction. Clostridium difficile-associated disease (CDAD) is treated using antibiotics, which often leads to the emergence of antibiotic-resistant bacteria such as vancomycin-resistant enterococci (VRE). This study estimated the impact of a non antibiotic treatment for CDAD on VRE prevalence. Methods. A previously published model describing the impact of in-hospital antibiotic use on VRE prevalence was adapted to include CDAD treatment. Simulations compared the prevalence of VRE when nonantibiotic versus antibiotic therapy was used. Results. Nonantibiotic treatment in 50% of CDAD patients resulted in an 18% relative reduction in the prevalence of VRE colonization compared with antibiotic use only. Sensitivity analysis found the model to be most sensitive to rates of antibiotic initiation and discontinuation, prevalence of VRE in admitted patients, length of stay of colonized patients, probability of CDAD acquisition, and hand-washing compliance. Conclusion. Nonantibiotic treatment of patients hospitalized with CDAD may significantly reduce the incidence of VRE colonization.