Treatment of experimental cystitis in the rat with a single dose of fosfomycin trometamol.

The therapeutic effectiveness of a single oral dose (60 and 200 mg/kg body weight) of fosfomycin trometamol (FT), norfloxacin, trimethoprim sulfamethoxazole (Bactrim) and pipemidic acid against experimental cystitis in the rat were compared. Infections were produced with clinical isolates of Klebsiella pneumoniae, Proteus mirabilis and Escherichia coli in a total of 135 Sprague-Dawley albino rats. Oral treatment with all four drugs consistently lowered the numbers of CFU in bladder tissue, especially E. coli and P. mirabilis. Fosfomycin trometamol appeared to be as effective as norfloxacin for treatment of E. coli cystitis even thoughs its minimal inhibitory concentration (MIC) in vitro is 100 times greater than that of the quinolonic antibiotic. Fosfomycin trometamol, pipemidic acid and Bactrim were equally effective against P. mirabilis infection, but FT was less active than norfloxacin or Bactrim for treatment of K. pneumonia cystitis. In conclusion, single dose treatment with fosfomycin trometamol was effective for treatment of experimental cystitis in the rat and might, by extrapolation, be of use in clinical practice for single dose treatment of uncomplicated urinary tract infections.