Objectives: To assess the effect of bladder instillations of hyaluronic acid (HA) on the rate of recurrence of urinary tract infection (UTI).
Patients and methods: Forty women (mean age 35 years) with a history of recurrent UTI received intravesical instillations of HA (40 mg in 50 mL phosphate-buffered saline) once weekly for 4 weeks then once monthly for 4 months. The UTI status was assessed over a prospective follow-up of 12.4 months and compared with the rates of UTI before instillation, determined by a retrospective review of patient charts covering 15.8 months.
Results: After HA treatment no patients had a UTI during the 5-month treatment phase and 28 (70%) were recurrence-free at the end of the follow-up. The mean (sd) rate of UTI per patient-year was 4.3 (1.55) before treatment and 0.3 (0.55) afterward (P < 0.001). The median time to recurrence after HA treatment was 498 days, compared with 96 days beforehand (P < 0.001). The tolerability was excellent, as side-effects were limited to nine patients who reported mild bladder irritation; no patient interrupted the treatment.
Conclusions: In this preliminary study, bladder instillations of HA had a significant effect on the rate of UTI in women with a history of recurrent UTIs. The bladder instillation of HA is an acceptable and promising therapeutic alternative in patients with recurrent UTI. Expanded placebo controlled clinical trials examining this application of HA are currently underway.