Resumen

SANCHEZ G, Damarys I et al. VIM- type metalloenzymes detected in clinical isolates of Pseudomonas aeruginosa in four Venezuelan hospitals. INHRR [online]. 2008, vol.39, n.2, pp.17-22. ISSN 0798-0477.

In recent years there has been a worldwide raise in the isolation of Pseudomonas aeruginosa strains with resistance to multiple antibiotics, being β-lactamase production the main cause of resistance to β-lactamic antibiotic (which are the only therapeutic option in many cases). The MBLs are an β-lactamic- degrading enzymatic family that have emerged as clinically relevant resistance determinants and are active against carbapemens, don´t hydrolise monobactams, have one or two zinc ions in its active site and are inhibited by metallic ions chelating agents such as EDTA and dipicolinic acid, but aren´t inhibited by β-lactamase inhibitors such as clavulanic acid, sulbactam or tazobactam. This report describes the detection of VIM-type MBLs by phenotypic and molecular methods in 9 carbapenemsresistant Pseudomonas aeruginosa strains isolated from clinical samples of four Venezuelan hospitals. By phenotypic methods it was evidenced that 100% of the strains were MBLs producers, and by final- point PCR it was determined that all the MBLs were from the VIM family, which confer high- level resistance to the β-lactamic antibiotics (except Aztreonam), and because they are carried by plasmids with the ability to transfer horizontally to other bacterial families, they can be responsible for therapeutic complications in an individual or the patients collective.

Palabras clave : Antibiotics; Pseudomonas aeruginosa; Carba-penems; metalo-b-lactamase.