Systematic review: antimicrobial urinary catheters to prevent catheter-associated urinary tract infection in hospitalized patients.

BACKGROUND The efficacy of antimicrobial urinary catheters in hospitalized patients is poorly defined. PURPOSE To assess currently marketed antimicrobial urinary catheters for preventing catheter-associated urinary tract infection (UTI). DATA SOURCES Electronic databases, conference proceedings, bibliographies, trialists, and catheter manufacturers (search dates, 1966 to June 2005). STUDY SELECTION Randomized and quasi-randomized trials of nitrofurazone-coated or silver alloy-coated antimicrobial urinary catheter use for less than 30 days; no language restriction. DATA EXTRACTION Study design, study sample, inclusion and exclusion criteria, allocation, blinding, UTI definition, ascertainment methods, and proportion developing symptomatic UTI (primary end point) or bacteriuria (secondary end point) were extracted by using a structured data collection instrument. DATA SYNTHESIS Twelve qualifying trials (13,392 total participants or catheters) were identified. They compared nitrofurazone-coated silicone (n = 3) or silver-coated latex (n = 9) catheters with silicone or latex catheters. No study addressed symptomatic UTI. All trials suggested protection against bacteriuria with test catheter use. However, effect size varied considerably and postrandomization exclusions were very common. Effect size was greatest in trials of nitrofurazone-coated catheters (all post-1995) and in pre-1995 silver alloy-coated catheter trials and was smallest in post-1995 silver alloy-coated catheter trials. Control group bacteriuria rate, control catheter type (latex vs. silicone), and patient sample (urology vs. other) also predicted effect size. Few studies addressed secondary bloodstream infection, mortality, costs, or microbial resistance. Short-term adverse effects were minimal. LIMITATIONS The study was limited by the number, size, and quality of studies and by lack of the following: intention-to-treat analyses, data on clinical end points, and trials comparing nitrofurazone-coated with silver alloy-coated catheters. CONCLUSIONS According to fair-quality evidence, antimicrobial urinary catheters can prevent bacteriuria in hospitalized patients during short-term catheterization, depending on antimicrobial coating and several other variables. Older data probably lack current relevance. Cost implications and effect on infectious complications remain undefined.