Resistance trends in gram-negative bacteria: surveillance results from two Mexican hospitals, 2005-2010.
BACKGROUND
Hospital-acquired infections caused by multiresistant gram-negative bacteria are difficult to treat and cause high rates of morbidity and mortality. The analysis of antimicrobial resistance trends of gram-negative pathogens isolated from hospital-acquired infections is important for the development of antimicrobial stewardship programs. The information obtained from antimicrobial resistant programs from two hospitals from Mexico will be helpful in the selection of empiric therapy for hospital-acquired gram-negative infections.


RESULTS
Two thousand one hundred thirty two gram-negative bacteria collected between January 2005 and December 2010 from hospital-acquired infections occurring in two teaching hospitals in Mexico were evaluated. Escherichia coli was the most frequently isolated gram-negative bacteria, with >50% of strains resistant to ciprofloxacin and levofloxacin. Klebsiella spp. showed resistance rates similar to Escherichia coli for ceftazidime (33.1% vs 33.2%), but exhibited lower rates for levofloxacin (18.2% vs 56%). Of the samples collected for the third most common gram-negative bacteria, Pseudomonas aeruginosa, >12.8% were resistant to the carbapenems, imipenem and meropenem. The highest overall resistance was found in Acinetobacter spp. Enterobacter spp. showed high susceptibility to carbapenems.


CONCLUSIONS
E. coli was the most common nosocomial gram-negative bacilli isolated in this study and was found to have the second-highest resistance to fluoroquinolones (>57.9%, after Acinetobacter spp. 81.2%). This finding represents a disturbing development in a common nosocomial and community pathogen.
Instituto de Patología Infecciosa y Experimental, Centro Universitario Ciencias de la Salud, Universidad de Guadalajara, Calle Hospital 308, Colonia El Retiro, CP 44280, Guadalajara, Jalisco, Mexico. rayomorfin@gmail.com
Rayo
R
Morfin-Otero
Juan Carlos
JC
Tinoco-Favila
Helio S
HS
Sader
Lorena
L
Salcido-Gutierrez
Hector Raul
HR
Perez-Gomez
Esteban
E
Gonzalez-Diaz
Luis
L
Petersen
Eduardo
E
Rodriguez-Noriega
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D024881:Drug Resistance, Bacterial / Q000187:drug effects; D062665:Epidemiological Monitoring; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000302:isolation & purification*; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D008800:Mexico / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D010641:Phenotype
D000900:Anti-Bacterial Agents