gentamicin-sulfate and Urinary-Tract-Infections

Phenotypic and genotypic methods were used to characterize extended-spectrum-beta-lactamase (ESBL)-producing Escherichia coli isolated in 2007 from 11 different Canadian medical centers. Of the 209 ESBL-producing E. coli isolates tested, 148 (71%) produced CTX-M-15, 17 (8%) produced CTX-M-14, 5 (2%) produced CTX-M-3, and 1 produced CTX-M-27. Overall, 96 (46%) of the ESBL producers belonged to clonal complex ST131, with the highest prevalence in Brampton, Calgary, and Winnipeg. ST131 is an important cause of community onset urinary tract infections due to ESBL-producing E. coli across Canada.

Topics: Bacterial Typing Techniques; beta-Lactamases; Canada; Community-Acquired Infections; Escherichia coli; Escherichia coli Infections; Escherichia coli Proteins; Humans; Microbial Sensitivity Tests; Prevalence; Urinary Tract Infections

Numerous antibiotics have proven to be effective at ameliorating the clinical symptoms of urinary tract infections (UTIs), but recurrent and chronic infections continue to plague many individuals. Most UTIs are caused by strains of uropathogenic Escherichia coli (UPEC), which can form both extra- and intracellular biofilm-like communities within the bladder. UPEC also persist inside host urothelial cells in a more quiescent state, sequestered within late endosomal compartments. Here, we tested a panel of 17 different antibiotics, representing seven distinct functional classes, for their effects on the survival of the reference UPEC isolate UTI89 within both biofilms and host bladder urothelial cells. All but one of the tested antibiotics prevented UTI89 growth in broth culture, and most were at least modestly effective against bacteria present within in vitro-grown biofilms. In contrast, only a few of the antibiotics, including nitrofurantoin and the fluoroquinolones ciprofloxacin and sparfloxacin, were able to eliminate intracellular bacteria in bladder cell culture-based assays. However, in a mouse UTI model system in which these antibiotics reached concentrations in the urine specimens that far exceeded minimal inhibitory doses, UPEC reservoirs in bladder tissues were not effectively eradicated. We conclude that the persistence of UPEC within the bladder, regardless of antibiotic treatments, is likely facilitated by a combination of biofilm formation, entry of UPEC into a quiescent or semiquiescent state within host cells, and the stalwart permeability barrier function associated with the bladder urothelium.

Topics: Animals; Anti-Bacterial Agents; Biofilms; Cell Membrane Permeability; Cells, Cultured; Drug Resistance, Bacterial; Endosomes; Escherichia coli; Escherichia coli Infections; Female; Humans; Mice; Mice, Inbred CBA; Microbial Sensitivity Tests; Recurrence; Urinary Bladder; Urinary Tract Infections; Urothelium

An increase in extended-spectrum-beta-lactamase (ESBL)-producing Escherichia coli has been observed in outpatient settings. Consequently, 100 ESBL-positive E. coli isolates from ambulatory patients with clinically confirmed urinary tract infections were collected by a single laboratory between October 2004 and January 2008. Antimicrobial susceptibility testing was carried out using the oral antibiotics fosfomycin, pivmecillinam, and nitrofurantoin and the parenteral antibiotic ertapenem. Susceptibility rates indicate that fosfomycin (97%), nitrofurantoin (94%), and pivmecillinam (85%) could be considered important oral treatment options.

Topics: Amdinocillin Pivoxil; Anti-Bacterial Agents; beta-Lactamases; Escherichia coli; Escherichia coli Infections; Fosfomycin; Humans; Microbial Sensitivity Tests; Nitrofurantoin; Urinary Tract Infections

Vertilmicin is a novel aminoglycoside antibiotic with potent activity against gram-negative and -positive bacteria in vitro. In this study, we further evaluated the efficacy of vertilmicin in vivo in systemic and local infection animal models. We demonstrated that vertilmicin had relatively high and broad-spectrum activities against mouse systemic infections caused by Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecalis. The 50% effective doses of subcutaneously administered vertilmicin were 0.63 to 0.82 mg/kg, 0.18 to 0.29 mg/kg, 0.25 to 0.99 mg/kg, and 4.35 to 7.11 mg/kg against E. coli, K. pneumoniae, S. aureus, and E. faecalis infections, respectively. The therapeutic efficacy of vertilmicin was generally similar to that of netimicin, better than that of gentamicin in all the isolates tested, and better than that of verdamicin against E. coli 9612 and E. faecalis HH22 infections. The therapeutic efficacy of vertilmicin was further confirmed in local infection models of rabbit skin burn infection and mouse ascending urinary tract infection.

Topics: Aminoglycosides; Animals; Anti-Bacterial Agents; Burns; Enterococcus faecalis; Escherichia coli; Female; Klebsiella pneumoniae; Male; Mice; Microbial Sensitivity Tests; Netilmicin; Rabbits; Skin Diseases; Staphylococcus aureus; Urinary Tract Infections