Resumen

CAMACHO-MOLINA, L et al. Phenotypic methods for detection of extended spectrum betalactamases in Escherichia coli and Klebsiella pneumoniae strains.. Rev. Soc. Ven. Microbiol. [online]. 2004, vol.24, n.1-2, pp.98-103. ISSN 1315-2556.

Escherichia coli and Klebsiella pneumoniae ESBL producer strains are a serious public health problem since cause therapeutic effectiveness loss to the betalactam antibiotics. In this study five methods were used to detect phenotypic ESBL production. 130 E. coli and 67 K. pneumoniae, isolated from bacteriological cultures carried out in the CRB-SAHUM, were studied. The screening and confirmatory NCCLS methods showed to be very good in the detection of ESBL positive strains, especially the methods based on the MIC. Additionally it was used the double disk method, this it demonstrated to be so sensitive and specific as the standardized methods of the NCCLS, since the results did not demonstrate significant differences. All the used methods had a similar performance; it is highly recommended the use of the double disk method, to be of low cost and easy of application in the daily routine of a bacteriology laboratory.

Palabras clave : Escherichia coli; Klebsiella pneumoniae; extended spectrum betalactamases..