Trends of 9,416 multidrug-resistant Gram-negative bacteria

Objective: a resistance of hospital-acquired bacteria to multiple antibiotics is a major concern worldwide. The objective of this study was to investigate multidrug-resistant (MDR) bacteria, clinical specimens, origin of specimen and trends, and correlate these with bacterial sensitivity and consumption of antimicrobials. Methods: 9,416 bacteria of nosocomial origin were evaluated in a tertiary hospital, from 1999 to 2008. MDR was defined for Gram-negative bacteria (GNB) as resistance to two or more classes/groups of antibiotics. Results: GNB MDR increased by 3.7 times over the study period (p < 0.001). Acinetobacter baumannii was the most prevalent (36.2%). Over the study period, there were significant 4.8-fold and 14.6-fold increases for A. baumannii and K. pneumoniae (p < 0.001), respectively. Sixty-seven percent of isolates of MDR GNB were isolated in intensive care units. The resistance of A. baumannii to carbapenems increased from 7.4 to 57.5% during the study period and concomitant with an increased consumption. Conclusion: that decade showed prevalence of GNB and a gradual increase in MDR GNB. There was an increase in carbapenem resistance of 50.1% during the study.