polycystic kidneys. Ciprofloxacin activity in cyst fluid from

Renal cyst infection in patients with polycystic kidney disease (PKD) is often unresponsive to standardantimicrobial therapy, in part because of the failure of most antibiotics to adequately penetrate cyst fluid.Ciprofloxacin, a new quinolone antibiotic, possesses in vitro activity against most pathogens likely to beencountered in renal cyst infection. Tostudy thepotential usefulness ofciprofloxacinfor thetreatmentofcystinfection, fluid from 70 cysts was obtained from seven patients with polycystic kidney disease who werereceivingthedrug.Cystswerecategorizedasnongradientorgradientbythesodiumconcentrationinthefluid.Theciprofloxacinconcentrationwithincystswasmeasured,andthecystfluidbactericidalactivityagainstlikelycystfluid pathogenswasdetermined. Themean