Biofilm in urinary catheters : impacts on health care and methods for quantification

Abstract: Biofilm is an increasing problem in the healthcare and have in urinary catheters long been associated with nosocomial urinary tract infections. The infections caused in 2002 alone 13,000 deaths in the US and annual costs have been estimated to over $400 million. These costs are however most likely underestimated. The analysis of biofilm is important to aid the work on increasing patient safety and reducing the financial implications. A literature study was conducted in order to recommend a method for quantification that was fast, accurate and versatile. Methods used for biofilm quantification are primarily based upon light absorption, light scattering and changes in impedance. A few methods utilizing these properties are spectrophotometry, flow cytometry and coulter counters. Samples of biofilm are usually collected via traditional scraping with a sterile blade or with sonication (ultrasound). Flow cytometry was considered the superior method for quantification along with sonication for sample collection. The survey therefore came to the conclusion that biofilm sample collection should be done with sonication and analysis with flow cytometry.