424Characterization and Profiling of Multi-Drug Resistant (MDR) Enterobacteriaceae From Latin America

Background. Enterobacteriaceae species are important pathogens responsible for a wide variety of serious infections. The tendency of these organisms to develop or acquire resistance to key antimicrobials can lead to MDR strains for which the therapeutic choices are limited. Therefore, tracking and profiling MDR strains is an important aspect of any surveillance initiative. In this study data from The Tigecycline Evaluation Surveillance Trial (TEST) program were analyzed to evaluate the profiles and characteristics of MDR populations from Latin America. Methods. Between 2008 and 2013 8,907 isolates of Enterobacteriaceae from Argentina, Brazil, Chile, Colombia, El Salvador, Guatemala, Honduras, Mexico, Panama, and Venezuela were locally collected, identified, and susceptibility tested (broth microdilution) according to CLSI guidelines. The data were centralized at IHMA for analysis of the MDR populations. MDR was defined as resistance to drugs from three or more different antimicrobial classes. Results. Of the 8,907 Enterobacteriaceae isolates 4,077 (45.8%) had a MDR phenotype; of those MDR 77.7% were from inpatients, 21.8% were blood isolates, 18.2% were from urinary tract specimens, 16.4% were from respiratory tract specimens, 7% were from intra-abdominal infections and 8.7% were from wounds. By species, 33.3 % of MDR were E. coli, 28.9% were K. pneumoniae, 21% were E. cloacae, and 9.1% were S. marcescens. The individual antimicrobial profiles for all Enterobacteriaceae and the MDR population were as follows: