Memorias del Instituto de Investigaciones en Ciencias de la Salud
versão On-line ISSN 1812-9528
FARINA, N et al. In vitroactivity of fluoroquinolones in gramnegative rods isolated from ambulatory patients urocultures. Mem. Inst. Investig. Cienc. Salud [online]. 2007, vol.5, n.1, pp. 15-18. ISSN 1812-9528.
Fluoroquinolones constitute a group of antibiotics frequently used in urinary tract infections (UTI), due to their high activity against enterobacteria, and their elimination route. The objetive of this study is to determine the resistance rate of gramnegative rods isolated from UTI to fluoroquinolones: ciprofloxacine, levofloxacine and gatifloxacine. In this study, all strains of gramnegative rods isolated from urine cultures from adult patients with UTI, attending the San Roque Laboratory, from June 2005 to March 2006 were included. Antibiotics susceptibility was determined by the diffusion method following the recommendation of NCCLS. Out of 380 strains, 81.7% was Escherichia coli, 11.6% Klebsiella pneumoniae, 3.4% Proteus mirabilis, 1% Enterobacter aerogenes, 0.8% Enterobacter cloacae, 0,5% Citrobacter koseri, 0.5% Citrobacter freundii and0.5% Klebsiella oxytoca. 17.6% of all isolates was resistant to all fluoroquinolones tested (58 strains of E. coli, 7 of K. pneumoniae, and 2 of E. cloacae). Resistance rate of E. coli to all fluoroquinolones was 18.7%, and 15.9% of K pneumoniae. One strain of E. coli, sensible to gatifloxacine, was intermediate to ciprofloxacine and levofloxacine. The three fluoroquinolones tested presented similar activity against gramnegative rods isolated from UTI. This resistance rate is relatively high, considering that for empirical use, the resistance rate to an antibiotic must no exceed 20%.
Palavras-chave : Urinary tract infection; fluoroquinolones; resistance.