Resumen

CALDERON E, Róger et al. Caracterización molecular de Klebsiella pneumoniae y Enterobacter cloacae productoras de ß-lactamasas de espectro extendido tipo SHV-5 en una unidad de cuidados intensivos neonatal de Lima. Rev. perú. med. exp. salud publica [online]. 2003, vol.20, n.3, pp.121-127. ISSN 1726-4634.

Objective: To elucidate the mechanisms involved in the transmission and antimicrobial resistance of Klebsiella pneumoniae and Enterobacter cloacae nosocomial isolates. Materials and methods: Genetic diversity was determinated for 10 bacterial isolates from hospitalized patients and environmental samples from a neonatal intensive care unit of a Lima hospital, using ribosomal and plasmidic DNA fingerprinting. Afterwards, the antimicrobial resistance was characterized as well as major factors using isofocusing electrophoresis. This was confirmed with Southern Blotting and PCR. Finally the resistance transfer ability was assessed using bacterial conjugation assays. Results: All K. pneumoniae and E. cloacae isolates displayed a unique plasmidic profile. E. cloacae isolates displayed the same genetic profile but, on the contrary, four K. pneumoniae genotypes highly related were found. In addition, it was established that all isolates produced extended spectrum ß-lactamase SHV-5-like transferable to other strains. Conclusions: This study suggests that the bacterial dissemination in neonates can be favored by the inadequate assistance in handling, by defective storage of milk for neonatal use and because of the indiscriminate use of antimicrobial agents, which contributed to the active transmission of genes responsible for antimicrobial resistance.

Palabras clave : Klebsiella pneumoniae; Enterobacter cloacae; Microbial drug resistanse; Neonatal intensive care units; nosocomial infections; Hospitals; Perú.

        · resumen en Español     · texto en Español     · Español ( pdf )