Epidemiology and Infection

Short Report


Rates of Stenotrophomonas maltophilia colonization and infection in relation to antibiotic cycling protocols

A. L. PAKYZa1 c1 and B. M. FARRa2

a1 School of Pharmacy, Virginia Commonwealth University, Richmond, VA, USA

a2 Department of Medicine, Division of Infectious Diseases and International Health, University of Virginia Health System, Charlottesville, VA, USA


This study evaluated whether antibiotic cycling programmes using broad-spectrum agents including carbapenems were associated with increased rates of colonization or infection by Stenotrophomonas maltophilia. Retrospective analyses of colonization or infection by S. maltophilia from 1992 to 2002 were conducted using University of Virginia Hospital clinical microbiology records of patients with any culture positive for S. maltophilia and hospital epidemiology records of nosocomial S. maltophilia infections. Incidence rates were calculated and compared for cycling and non-cycling periods. No significant differences were found in incidence rates of S. maltophilia isolates between cycling and non-cycling periods, but there was a significant secular increase in the hospital-wide rate of infections caused by S. maltophilia (P=0·01728). Antibiotic cycling protocols were not associated with a significantly increased rate of colonization of S. maltophilia as determined by the frequency of patients having at least one positive routine clinical culture in this hospital.

(Accepted April 29 2009)

(Online publication May 27 2009)


c1 Author for correspondence: A. L. Pakyz, Pharm.D., M.S., Virginia Commonwealth University, School of Pharmacy, Medical College of Virginia Campus, 410 North 12th Street, PO Box 980583, Richmond, VA 23298, USA. (Email: apakyz@vcu.edu)