7432-s and temocillin

Increasing resistance in Escherichia coli and Klebsiella pneumoniae to firstline antibiotics makes therapeutic options for urinary tract infections (UTIs) challenging. This study investigated the in vitro efficacies of 6 antibiotics against multidrug resistant (MDR) uropathogens.. Minimum inhibitory concentrations to ceftibuten, cefpodoxime, fosfomycin, mecillinam, temocillin, and trimethoprim were determined against 155 MDR-isolates of E. coli and K. pneumoniae. The presence of extended-spectrum beta-lactamases (ESBL) and plasmid-borne AmpC enzymes was determined by phenotypic testing with genotyping performed by multiplex polymerase chain reaction.. Temocillin demonstrated highest susceptibility rates for both E. coli (95%) and K. pneumoniae (95%) when breakpoints for uncomplicated UTIs were applied; however, temocillin susceptibility was substantially lower when "systemic infection" breakpoints were used. Fosfomycin demonstrated the best in vitro efficacy of the orally available agents, with 78% and 69% of E. coli and K. pneumoniae isolates susceptible, respectively. The next most effective antibiotics were ceftibuten (45%) and mecillinam (32%). ESBL and ampC genes were present in 47 (30%) and 59 (38%) isolates.. This study demonstrated few oral therapeutic options for MDR-uropathogens, with fosfomycin demonstrating the best in vitro activity.

Topics: Amdinocillin; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Cefpodoxime; Ceftibuten; Ceftizoxime; Cephalosporins; Drug Resistance, Multiple, Bacterial; Escherichia coli; Escherichia coli Infections; Fosfomycin; Genotype; Humans; In Vitro Techniques; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Multiplex Polymerase Chain Reaction; Penicillins; Singapore; Trimethoprim; Urinary Tract Infections