Showing papers by "Maria Virginia Villegas published in 2007"
TL;DR: In Medellin, Colombia, three Pseudomonas aeruginosa isolates with high-level carbapenem resistance and an isolate of Citrobacter freundii with reduced susceptibility to imipenem produced the plasmid-mediated class A carbapENemase KPC-2.
Abstract: In Medellin, Colombia, three Pseudomonas aeruginosa isolates with high-level carbapenem resistance (MIC ≥ 256 μg/ml) and an isolate of Citrobacter freundii with reduced susceptibility to imipenem produced the plasmid-mediated class A carbapenemase KPC-2. This is the first report of a KPC-type β-lactamase identified outside of the family Enterobacteriaceae.
299 citations
TL;DR: This report describes the first description of widespread dissemination of OXA-23 in South America and states that one clone was present in two hospitals within one city, while another had spread between two hospitals in different cities.
Abstract: During 2005, 66 carbapenem-resistant isolates of Acinetobacter baumannii were collected from seven tertiary-care hospitals participating in a nationwide surveillance network in Colombia. The isolates were multidrug resistant and produced the carbapenemases OXA-23 and OXA-51. Forty-five belonged to four clones while 21 were unique pulsotypes. One clone was present in two hospitals within one city, while another had spread between two hospitals in different cities. Blood, secretions, and abdominal fluids were the most frequent sites of isolation. This is the first description of widespread dissemination of OXA-23 in South America.
105 citations
TL;DR: Current data on the most important mechanisms of resistance in prevalent Gram-negative pathogens as well as newer therapeutic options are described.
Abstract: Gram-negative bacteria are the dominant killers among bacterial pathogens in the intensive care unit. Antibiotic resistance has become a threat in hospital settings and efforts are being made to understand the underlying mechanisms. This review describes current data on the most important mechanisms of resistance in prevalent gram-negative pathogens as well as newer therapeutic options.
59 citations
22 Dec 2007
TL;DR: Pseudomonas aeruginosa is a nonfermenting Gram-negative bacterium that has minimal nutritional requirements and can survive on a wide variety of surfaces and in aqueous environments as mentioned in this paper.
Abstract: Pseudomonas aeruginosa is a nonfermenting Gram-negative bacterium that has minimal nutritional requirements and can survive on a wide variety of surfaces and in aqueous environments. Pseudomonas has numerous reservoirs in the hospital, including sinks, respiratory equipment, cleaning solutions, flowers, and uncooked vegetables, and it occasionally may be recovered from the hands of medical personnel. The pathogenesis of P. aeruginosa may be divided into three stages: bacterial attachment and colonization, local invasion and dissemination, and systemic disease; although disease progression can stop at any stage. The P. aeruginosa isolated from the sputum of patients with cystic fibrosis are commonly mucoid variants that produce the exopolysaccharide alginate. Antibiotic resistance in P. aeruginosa is an increasing problem, posing many therapeutic challenges. Many strains of P. aeruginosa exhibiting beta-lactam resistance reflect a prior exposure of the patients to broad-spectrum beta-lactams. P. aeruginosa is often resistant to a variety of broad-spectrum antimicrobial agents, making it a formidable pathogen.
1 citations