Bacterial colonization, species diversity and antimicrobial susceptibility patterns of indwelling urinary catheters from postpartum mothers attending a Tertiary Hospital in Eastern Uganda

Background Postpartum urinary Catheter-Related Infections (CRIs) are a significant cause of maternal sepsis. Several studies done have reported the presence of mixed populations of bacteria with a significant increase in Extended-Spectrum Beta-Lactamase (ESBL) Enterobacteriaceae spps, Methicillin-Resistant Staphylococcus aureus (MRSA), Multi-Drug Resistant (MDR) bacteria in urine and blood cultures of catheterized patients despite the use of prophylactic antibiotics. This study aimed at determining the bacterial species diversity and susceptibility patterns of indwelling urinary catheters from postpartum mothers attending Mbale Regional Referral Hospital (MRRH). Methods A cross-sectional study employing quantitative and qualitative was carried out in MRRH among postpartum mothers with urinary catheters and their care-takers. The purposive non-random sampling strategy was used to collect data using an interviewer-administered questionnaire for the quantitative data collection and in-depth interviews for qualitative data collection. All the data collection tools used were developed, pretested and validated. At the point of de-catheterization, Catheter tips from enrolled participants were cut about 2-3cm below the balloon aseptically into test-tube containing peptone water, sonication technique employed, and incubation done 24hours then cultured to ensure phenotypic identification. An antibiotic sensitivity test was performed using the disc diffusion method following Clinical and Laboratory Standards Institute (CLSI) guidelines. Quantitative data collected was entered in Microsoft Excel and then exported to STATA14 for statistical analysis. Thematic analysis was used to analyse and organise qualitative data by an inductive coding method using Nvivo 12 software. Results In this study, 208 postpartum mothers participated, the majority of whom were caesarean section mothers of age range 20–24 years and 17 care-takers with a median age of 32 years. The prevalence of catheter tips bacterial colonisation was 98% despite 88.5% of the participants being on broad-spectrum antibiotics. The average duration of catheterisation was 2 days. All bacteria isolates were potential uro-pathogens with a mean occurrence of 2 bacteria species in each urinary catheter tip. The rates of MDR to commonly used antibiotics were high. The urinary catheter size of greater than F14 and duration of catheterization greater than 2 days were significantly associated with the number of bacterial species isolated from each sample. The maintenance care and knowledge of care-urinary catheter care among the care-takers was found sub-optimal. Conclusion There was a high prevalence of catheter colonisation with bacterial spps diversity averaging 2 spps per sample despite use of broad spectrum antibiotics. The MDR rates were high, which calls for routine culture and sensitivity. Health workers practicing obstetric medicine need to pay attention to catheter sizes during catheterisation and its duration. Health education should be part of antenatal and postnatal care education.

The Aging Behavior of Polyurethane-based Ureteral Catheters

Ureteral catheters, commonly known as double j stents according to their specific shape, are largely used worldwide with good results to assure proper renal drainage and to overpass ureteral obstacles successfully. This study deals with the aging behavior of polyurethane-based urinary catheters, explanted at different time intervals: 22 days, 29 days, three months, and eight months respectively. TGA (Thermogravimetric analyses) tests showed significant differences in the thermal behavior of polyurethane-based material, especially at eight months, where a higher thermostability was noticed. Also, the DSC (Differential Scanning Calorimetry) curves presented different shapes for the samples of polyurethane-based urinary catheters after three months and eight months. FTIR (Fourier-Transform Infrared Spectrometry) spectra gave a detailed picture of the chemical trans-formation which has occurred within the material at eight months. All the analyses gave an overview of the aging process of polyurethane-based urinary catheters and showed insights into the chemical/ physical transformations that the polymeric material suffers from prolonged usage.

I-DECIDED® – A decision tool for assessment and management of invasive devices in the hospital setting

Indwelling medical devices, including vascular access and urinary catheters, pose a risk for infection, and therefore daily assessment and consideration of their continued need is a patient safety priority. The I-DECIDED® device assessment and decision tool is an evidence-based checklist, designed to improve the assessment, care, and timely removal of invasive devices in acute hospitalized patients. This paper explains each step of the tool, with rationale for inclusion.

Quality Improvement Initiative: Foley Catheters in Patients Undergoing Pectus Deformity Repair

Background and Hypothesis: Pectus excavatum and carinatum are sternal deformities that often require surgeries with significant postoperative pain that can limit a patient’s ability to void. An indwelling urinary catheter is placed for the operation, but is often removed on the first postoperative day due to concerns of infection, which begs the necessity of these catheters in the first place. In this study, we hypothesized that there would be no increased risk of urinary retention or urinary tract infection irrespective of whether urinary catheters were utilized. Experimental Design: A pre/post quality improvement study was undertaken of patients undergoing pectus excavatum/carinatum repair between June 1, 2015 and May 31, 2022. The pre intervention group spanned from June 1, 2015 to May 31, 2021, where Foley catheters were placed intraoperatively and removed the first postoperative day. Pediatric surgery and anesthesia groups changed practice effective June 1, 2021 and decided to no longer utilize urinary catheters in pectus repairs. Pre-intervention patients were acquired through the surgery billing database. Post-intervention patients were acquired prospectively. Rates of urinary retention (any event requiring mechanical intervention for voiding) and urinary tract infections (UTI, >100,000 CFU bacteria/mL urine) were compiled into REDCap. Data are expressed as percent of the total cohort. Results: Of 179 patients undergoing pectus repair (162 Excavatum, 17 Carinatum), 12 patients (6.7%) in the pre-intervention group experienced urinary retention. Of these, 9 received in/out catheterization, 1 had a Foley catheter replaced, and 2 underwent in/out catheterization and had a Foley replaced. There were no urinary tract infections recorded among the pre-intervention group. Conclusion and Potential Impacts: Urinary retention and UTI are rare in patients who have an indwelling urinary catheter. Data acquired over the next year from the post-intervention group will help determine the true necessity for these catheters in the perioperative pectus population.

Inhibiting Host Protein Deposition on Urinary Catheters Reduces Urinary Tract Infections

SummaryMicrobial adhesion to medical devices is common for hospital-acquired infections, particularly for urinary catheters. If not properly treated these infections cause complications and exacerbate antimicrobial resistance. Catheter use elicits bladder inflammation, releasing host serum-proteins, including fibrinogen, into the bladder, which deposit on the urinary catheter. Enterococcus faecalis uses fibrinogen as a scaffold to bind and persist in the bladder despite antibiotic treatments. Inhibition of fibrinogen-pathogen interaction significantly reduces infection. Here, we show deposited fibrinogen is advantageous for uropathogens, suggesting that targeting catheter protein deposition may reduce colonization creating an effective intervention. Hostprotein deposition was reduced, using liquid-infused catheters, resulting in decreased colonization on catheters, in bladders, and dissemination in vivo. Furthermore, proteomics revealed a significant decrease in deposition of host-secreted proteins on liquid-infused catheter surfaces. Our findings suggest targeting microbial binding scaffolds may be an effective antibiotic-sparing intervention for use against catheter-associated urinary tract infections and other medical device infections.

Simultaneous Ultrasound-Assisted Hybrid Polyzwitterion/Antimicrobial Peptide Nanoparticles Synthesis and Deposition on Silicone Urinary Catheters for Prevention of Biofilm-Associated Infections

Nosocomial infections caused by antibiotic-resistant bacteria are constantly growing healthcare threats, as they are the reason for the increased mortality, morbidity, and considerable financial burden due to the poor infection outcomes. Indwelling medical devices, such as urinary catheters, are frequently colonized by bacteria in the form of biofilms that cause dysfunction of the device and severe chronic infections. The current treatment strategies of such device-associated infections are impaired by the resistant pathogens but also by a risk of prompting the appearance of new antibiotic-resistant bacterial mechanisms. Herein, the one-step sonochemical synthesis of hybrid poly(sulfobetaine) methacrylate/Polymyxin B nanoparticles (pSBMA@PM NPs) coating was employed to engineer novel nanoenabled silicone catheters with improved antifouling, antibacterial, and antibiofilm efficiencies. The synergistic mode of action of nanohybridized zwitterionic polymer and antimicrobial peptide led to complete inhibition of the nonspecific protein adsorption and up to 97% reduction in Pseudomonas aeruginosa biofilm formation, in comparison with the pristine silicone. Additionally, the bactericidal activity in the hybrid coating reduced the free-floating and surface-attached bacterial growth by 8 logs, minimizing the probability for further P. aeruginosa spreading and host invasion. This coating was stable for up to 7 days under conditions simulating the real scenario of catheter usage and inhibited by 80% P. aeruginosa biofilms. For the same time of use, the pSBMA@PM NPs coating did not affect the metabolic activity and morphology of mammalian cells, demonstrating their capacity to control antibiotic-resistant biofilm-associated bacterial infections.