High-resolution imaging reveals microbial biofilms on patient urinary catheters despite antibiotic administration

• Published in: World journal of urology Vol. 38; no. 9; pp. 2237 - 2245
• Main Authors: Walker, Jennifer N., Flores-Mireles, Ana L., Lynch, Aaron J. L., Pinkner, Chloe, Caparon, Michael G., Hultgren, Scott J., Desai, Alana
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-09-2020; Springer Nature B.V
• Subjects: Anti-Bacterial Agents - pharmacology; Anti-Bacterial Agents - therapeutic use; Antibiotics; Bacteria - isolation & purification; Bacteriuria; Bacteriuria - microbiology; Biofilms; Biofilms - drug effects; Catheterization; Catheters; Equipment Contamination; Female; Fluorescent Antibody Technique; Humans; Immunofluorescence; Intubation; Male; Medicine; Medicine & Public Health; Microscopy, Electron, Scanning; Morbidity; Nephrology; Oncology; Original Article; Patients; Scanning electron microscopy; Urinalysis; Urinary Catheters - microbiology; Urinary tract; Urinary tract infections; Urine; Urology; CAUTI; Catheter colonization; Asymptomatic catheter-associated bacteriuria; Urinary catheterization; Microbial biofilms
• ISSN: 0724-4983; 1433-8726
• DOI: 10.1007/s00345-019-03027-8

Purpose
Catheter-associated urinary tract infections (CAUTIs) are a significant cause of morbidity worldwide, as they account for 40% of all hospital-associated infections. Microbial biofilm formation on urinary catheters (UCs) limits antibiotic efficacy, making CAUTI extremely difficult to treat. To gain insight into the spatiotemporal microbe interactions on the catheter surface we sought to determine how the presence or absence of bacteriuria prior to catheterization affects the organism that ultimately forms a biofilm on the UC and how long after catheterization they emerge.
Methods
Thirty UCs were collected from patients who received a urine culture prior to catheterization, a UC, and antibiotics as part of standard of care. Immunofluorescence imaging and scanning electron microscopy were used to visualize patient UCs.
Results
Most patients did not have bacteria in their urine (based on standard urinalysis) prior to catheterization, yet microbes were detected on the majority of UCs, even with dwell times of < 3 days. The most frequently identified microbes were
Staphylococcus epidermidis
,
Enterococcus faecalis
, and
Escherichia coli
.
Conclusions
This study indicates that despite patients having negative urine cultures and receiving antibiotics prior to catheter placement, microbes, including uropathogens associated with causing CAUTI, could be readily detected on UCs with short dwell times. This suggests that a potential microbial catheter reservoir can form soon after placement, even in the presence of antibiotics, which may serve to facilitate the development of CAUTI. Thus, removing and/or replacing UCs as soon as possible is of critical importance to reduce the risk of developing CAUTI.