Login to Access Video or Poster Abstract: MP23-17
Sources of Funding: Stony Brook School of Medicine (AN, GTW); NIH NRSA F30 (GTW).

Introduction

The majority of hospital-acquired urinary tract infections (UTIs) are catheter-associated UTIs (CAUTIs), which are associated with increased morbidity and mortality in patients, with 13,000 attributed deaths annually. CAUTIs are also associated with increased length of hospital stays and 0.4-0.5 billion USD in annual healthcare costs, as well as unnecessary antimicrobial use. The formation of biofilms (groups of bacterial cells that adhere to one another and to a fixed surface) on catheters is critical to the development and persistence of CAUTI, as biofilms function as both barriers to antibiotics and reservoirs of microbes. We sought to determine the natural history of biofilm formation on urinary catheters. In particular, we were interested in the starting location(s) of biofilm formation, and whether biofilms predominated proximally or distally on catheters, their timing and manner of progression, and whether catheter biofilm formation was predominantly extraluminal or intraluminal.

Methods

Foley catheters (n=19) were collected from outpatient and inpatient clinics at a large university medical center from post-surgical patients at 1 to 28 days indwelling time. Each catheter was sectioned and stained, and biofilms were quantitated using spectrophotometry.

Results

Short-term catheters (indwelling <1 week) displayed predominant biofilm formation at the proximal (bladder-exposed) end, whereas long-term catheters (indwelling 3-4 weeks) displayed significant biofilm formation throughout all segments. Biofilm growth on short-term catheters was predominantly extra-luminal, whereas long-term catheters demonstrated significant extra- and intra-luminal biofilm staining.

Conclusions

The results of this preliminary study inform approaches to developing novel strategies to prevent and eradicate bacterial biofilms from urinary catheters. For example, this study suggests that catheter-coating techniques targeting the extraluminal surface of the proximal end of the urinary catheter may contribute to a delay of biofilm formation, and reduce the overall risk of CAUTI. Efforts are under way to further investigate biofilm progression with larger sample sizes, and to determine how a reduction in biofilm formation and progression may contribute to reduced CAUTI risk.

Funding

Stony Brook School of Medicine (AN, GTW); NIH NRSA F30 (GTW).