Clearance of Candida colonizing the urinary bladder by a two-day amphotericin B irrigation

The minimum duration of continuous amphotericin B irrigation (50 mg/liter/day) required to clear the candida colonizing the urinary bladder was investigated. Eleven in vitro experiments revealed a consistent candidicidal effect within 48 hours with 25 and 5 mg/l of amphotericin B concentrations attainable in the bladder. Hospitalized nursing home patients with candiduria were treated with two-day irrigation according to the protocol. The protocol consists of the use of a newly inserted catheter for the irrigation, subsequent washout of the residual drug, and immediate sampling of urine for microscopic examination and culture after the procedure. In 47 of 65 (72.3%) cases yeast was cleared. In the remaining 18 the candida persisted. Of the latter, ten received additional irrigation for an average of 7.3 days (range: 4-12 days). In all ten cases funguria continued. Two-day irrigation saves time and expense, and is as effective as the five-day procedure in eradicating the yeast on bladder mucosa. Because of the relatively short irrigation time, the protocol may be useful in clinical evaluation of the site of urinary candidiasis.