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Maria Virginia Villegas

Publications and source records attributed to Maria Virginia Villegas.

7 recordsLinked to original sources

First detection of the plasmid-mediated class A carbapenemase KPC-2 in clinical isolates of Klebsiella pneumoniae from South America.

The plasmid-mediated class A carbapenemase KPC-2 was isolated from unrelated Klebsiella pneumoniae isolates in Medellin, Colombia. These KPC enzymes are the first from South America and the second isolation outside of the United States. The expanding geographic spread of KPC carbapenemases underscores the importance of clinical recognition of these enzymes.

Anti-Bacterial Agents↗

First detection of metallo-beta-lactamase VIM-2 in Pseudomonas aeruginosa isolates from Colombia.

Carbapenem resistance rates in Pseudomonas aeruginosa isolates in Colombia, as in many South American countries, are high for reasons that remain unclear. From our nationwide network, we describe the first detection of the metallo-beta-lactamase VIM-2 in clinical isolates of P. aeruginosa from multiple cities within Colombia. Metallo-beta-lactamases were not detected in the two centers with the highest imipenem resistance rates. Clonality was noted in five of the eight centers with strains meeting the criteria for molecular typing. The high carbapenem resistance in P. aeruginosa in Colombia may be attributable to a combination of factors, including the presence of metallo-beta-lactamases and nosocomial transmission.

Colombia↗

[Antimicrobial resistance in gram negative bacteria isolated from intensive care units of Colombian hospitals, WHONET 2003, 2004 and 2005].

INTRODUCTION: Surveillance systems play a key role in the detection and control of bacterial resistance. It is necessary to constantly collect information from all institutions because the mechanisms of bacterial resistance can operate in different ways between countries, cities and even in hospitals in the same area. Therefore local information is important in order to learn about bacterial behaviour and design appropriate interventions for each institution. Between January 2003 and December 2004, the Centro Internacional de Entrenamiento e Investigaciones Médicas (CIDEIM) developed a surveillance project in 10 tertiary hospitals in 6 cities of Colombia. OBJECTIVES: Describe the trends of antibiotic resistance among the isolates of Escherichia coli, Klebsiella pneumoniae, Pseudomona aeruginosa, Acinetobacter baumannii and Enterobacter cloacae, five of the most prevalent nosocomial Gram negative pathogens. MATERIALS AND METHODS: The susceptibility tests were performed by automated methods in 9 hospitals and by Kirby Bauer in 1 hospital. Antibiotics with known activity against Gram negatives, according to the Clinical Laboratory Standards Institute guidelines, were selected. The laboratories performed internal and external quality controls. During the study period, the information was downloaded monthly from the databases of each microbiology laboratory and sent to CIDEIM where it was centralized in a database using the system WHONET 5.3. RESULTS: The high resistance rates reported especially for A. baumannii, evidenced the presence of multidrug resistant bacteria in both ICUs and wards at every studied institution. CONCLUSIONS: The creation of a national surveillance network to improve our capabilities to detect, follow up, and control the antibiotic resistance in Colombia is urgently needed.

Colombia↗

Prevalence and characterization of extended-spectrum beta-lactamases in Klebsiella pneumoniae and Escherichia coli isolates from Colombian hospitals.

Gram-negative pathogens harboring extended-spectrum beta-lactamases (ESBL) are widely prevalent in Latin America, but little is known about their prevalence in Colombia. A network of 8 tertiary care hospitals in Bogotá, Medellín, and Cali, Colombia, was formed in January 2002 to determine the prevalence of ESBL-producing Klebsiella pneumoniae and Escherichia coli. We characterized and established the molecular epidemiology of ESBLs from these hospitals. Data from 1074 E. coli and 394 K. pneumoniae isolates were obtained from hospital laboratories during 6 months. Isolates resistant to third-generation cephalosporins or aztreonam were sent to a central laboratory. The prevalence of strains with this phenotype was 32.6% in K. pneumoniae and 11.8% in E. coli from the intensive care units, with slightly lower percentages from wards. Although TEM and SHV enzymes were present, the dominant class was CTX-M. Molecular typing of chromosomal DNA showed that most strains were not clonal.

Anti-Bacterial Agents↗

CTX-M-12 beta-lactamase in a Klebsiella pneumoniae clinical isolate in Colombia.

We describe the detection of the CTX-M-12 beta-lactamase from a clinical isolate of Klebsiella pneumoniae in Colombia. Screening of nosocomial Klebsiella spp. and Escherichia coli isolates from a network of teaching hospitals revealed the presence of CTX-M enzymes in multiple cities. This is the first description of CTX-M in Colombia.

Colombia↗

Acinetobacter outbreaks, 1977-2000.

This review of Acinetobacter outbreaks summarizes factors related to the presence and recognition of organism transmission and describes the implementation of control and prevention measures directed at limiting spread. Exogenous transmission of Acinetobacter should be considered when infections are endemic and when case rates increase. Increasing or new antimicrobial resistances in a collection of isolates also suggest transmission, and transmission can be definitively confirmed when isolates are found to be indistinguishable from or related to one another by a discriminatory genotyping test. An investigation for a common source should be conducted. When a common source cannot be found and eliminated, or once an endemically transmitted organism is established, containment or prevention efforts may require aggressive interventions, complex interventions, or both. Colonization at multiple sites, the relative ease of induction of antibiotic resistance in the organism following patient exposure to multiple drugs, and long-term environmental survival provide enhanced opportunities for the transmission of Acinetobacter between and among patients. New approaches and interventional trials are needed to define effective measures for the prevention and control of Acinobacter infections.

Acinetobacter↗