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Abstract

Similar to previous smaller trials using Escherichia coli 83972, our multicenter study using the genetically modified E. coli Hu2117 demonstrated that bacterial interference significantly reduces the incidence of symptomatic catheter-associated urinary tract infection. The success rate of establishing long-term (>1-month) bladder colonization with E. coli 83972 varied from 25% to 62%. 1 Wullt B. Connell H. Rollano P. et al. Urodynamic factors influence the duration of Escherichia coli bacteriuria in deliberately colonized cases. J Urol. 1998; 159: 2057-2062 Abstract Full Text Full Text PDF PubMed Scopus (65) Google Scholar , 2 Darouiche R.O. Thornby J.I. Cerra-Stewart C. Donovan W.H. Hull R.A. Bacterial interference for prevention of urinary tract infection: a prospective, randomized, placebo-controlled, double-blind pilot trial. Clin Infect Dis. 2005; 41: 1531-1534 Crossref PubMed Scopus (95) Google Scholar , 3 Hull R.A. Donovan W.H. Del Terzo M. et al. Role of type 1 fimbriae- and P fimbriae-specific adherence in colonization of the neurogenic human bladder by Escherichia coli. Infect Immun. 2002; 70: 6481-6484 Crossref PubMed Scopus (30) Google Scholar Although the basis for the modest bladder colonization success is not well known, it could be multifactorial. It is unlikely that genetic modification of E. coli further compromised the colonization, because earlier studies revealed no difference in bladder colonization between E. coli Hu2117 and wild-type E. coli 83972. 3 Hull R.A. Donovan W.H. Del Terzo M. et al. Role of type 1 fimbriae- and P fimbriae-specific adherence in colonization of the neurogenic human bladder by Escherichia coli. Infect Immun. 2002; 70: 6481-6484 Crossref PubMed Scopus (30) Google Scholar One reason for the low-colonization success in the present study is the decline in patient participation after each colonization attempt. All participating subjects had impaired mobility and to travel to the clinic for the 3-day outpatient inoculation protocol represented a significant burden. More convenient bladder colonization protocols are needed before this promising application of bacterial interference can be widely adopted. The use of catheters coated with nonpathogenic bacteria could eliminate the need for repeated clinic visits and improve patient compliance. In that regard, the results from a small, single-arm, clinical trial and in vitro studies suggested that catheters precoated with E. coli 83972 or its derivatives could be useful. 4 Trautner B.W. Hull R.A. Thornby J.I. Darouiche R.O. Coating urinary catheters with an avirulent strain of Escherichia coli as a means to establish asymptomatic colonization. Infect Control Hosp Epidemiol. 2007; 28: 92-94 Crossref PubMed Scopus (51) Google Scholar Editorial CommentUrologyVol. 78Issue 2PreviewIn the paper “A Randomized, Placebo-controlled, Double-blind, Multi-center Trial of Bacterial Interference for Prevention of Urinary Tract Infection,” the authors hypothesize that insertion into the bladder of a modified Escherichia coli strain of E. coli Hu2117 will cause asymptomatic bladder colonization. Full-Text PDF