Pilot trial of bacterial interference for preventing urinary tract infection

Objectives. To examine the safety and efficacy of bacterial interference in preventing symptomatic urinary tract infection (UTI). Methods. A prospective, nonrandomized, pilot clinical trial was conducted i n patients with spinal cord injury who had neurogenic bladder and had frequ ent episodes of symptomatic UTI. The bladder of patients was inoculated wit h a nonpathogenic prototype of Escherichia coli 83972. The rate of symptoma tic UTI in successfully colonized patients while colonized with E. coli 839 72 was compared with (a) their own baseline prestudy rate and (b) the rate of symptomatic UTI in patients who were not successfully colonized. Results. Of 44 inoculated patients, 30 (68%) became colonized with E. coli 83972 for 1 month or longer. Only two episodes of symptomatic UTI occurred in the group of 30 patients while colonized with E. coli 83972 (a total of 34 patient-years), and none was attributed to E. coli 83972. The group of 3 0 patients experienced a 63-fold reduction in the rate of symptomatic UTI w hile colonized with E. coli 83972 versus their baseline prestudy period (me an 0.06 versus 3.77 episodes of symptomatic UTI/patient-year, P <0.001). Th e rate of symptomatic UTI was also 33-fold lower in this group of 30 patien ts while colonized with E. coli 83972 than in the well-matched group of 14 patients who were not successfully colonized (mean 0.06 versus 1.80 episode s of symptomatic UTI/patient-year, P <0.001). Conclusions. The results of this pilot study indicate that bacterial interf erence using E. coli 83972 may be safe and effective in preventing UTI. URO LOGY 58: 339-344, 2001. (C) 2001, Elsevier Science Inc.