Efficacy and safety of urinary catheters with silver alloy coating in patients with spinal cord injury: a multicentric pragmatic randomized controlled trial. The ESCALE trial

Materials-based incidence of urinary catheter associated urinary tract infections and the causative micro-organisms: systematic review and meta-analysis

BACKGROUND

Both long (> 30 days) and short-term (≤ 30 days) catheterisation has been associated with urinary tract infections (UTIs) due to the invasive nature of device insertion through the urethra. Catheter associated Urinary Tract Infections (CAUTIs) are common (prevalence of ~ 8.5%) infections which can be treated with antibiotics; however, CAUTIs are both expensive to treat and contributes to the antibiotic usage crisis. As catheters are unlikely be replaced for the management of patients' urination, ways of reducing CAUTIs are sought out, using the catheter device itself. The aim of this review is to assess the incidence of CAUTI and the causative micro-organisms when different urinary catheter devices have been used by humans, as reported in published research articles.

METHODS

A Systematic Literature Review was conducted in Ovid Medline, Web of Science and PubMed, to identify studies which investigated the incidence of UTI and the causative micro-organisms, in patients with different urinary catheter devices. The articles were selected based on a strict set of inclusion and exclusion criteria. The data regarding UTI incidence was extracted and calculated odds ratio were compared across studies and pooled when types of catheters were compared. CAUTI causative micro-organisms, if stated within the research pieces, were also gathered.

RESULTS

A total of 890 articles were identified, but only 26 unique articles met the inclusion/exclusion criteria for this review. Amongst the large cohort there were catheters of materials silicone, latex and PVC and catheter modifications of silver nanoparticles and nitrofurantoin antibiotics. The meta-analysis did not provide a clear choice towards a single catheter against another although silver-based catheters, and silver alloy, appeared to statistically reduce the OR of developing CAUTIs. At genus level the three commonest bacteria identified across the cohort were E. coli, Enterococcus spp. and Pseudomonas spp. whilst considering only at the genus level, with E. coli, Klebsiella pneumonia and Enterococcus faecalis most common at the species-specific level.

CONCLUSIONS

There does not appear to be a catheter type, which can significantly reduce the incidence of CAUTI's in patients requiring catheterisation. Ultimately, this warrants further research to identify and develop a catheter device material that will reduce the incidence for CAUTIs.

Medicated Foley Catheters Do Not Prevent Catheter-Associated Urinary Tract Infection: A Systematic Review of Randomized Controlled Trials

Infections of the urinary tract are among some of the most common infections treated in clinical practice. Numerous risk factors play an intrinsic role in the development of such infections, namely: age, sexual intercourse, prolonged use of feminine hygiene products, instrumentation, pregnancy, sexually transmitted infections, obstructive uropathy such as prostatic enlargement or urethral strictures, compromised immunity, and constipation. A major cause of urinary tract infections (UTIs) in hospitalized patients is catheter-associated urinary tract infections (CAUTIs). This systematic review aims to identify the causative agents and risk factors and to determine whether nitrofurazone, silver alloy, or zinc oxide-impregnated or coated/medicated Foley catheters, or non-medicated (standard) Foley catheters, can reduce the incidence of CAUTIs. A systematic review was conducted on the following databases: PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), Trip medical database, and Google Scholar. A combination of keywords and Boolean operators was used ((((urinary tract infections) OR (urinary catheterization)) OR (prevention AND control)) ) AND (catheter-associated infections) for data extraction. All the randomized controlled clinical trials (RCTs) completed and available between January 1, 2005, and June 30, 2024, which focused on the prevention of CAUTIs, were screened thoroughly and were included in this systematic review. The Cochrane risk-of-bias tool for randomized trials (RoB 2) tool was used for risk of bias assessment. The Robvis visualization tool (McGuinness, LA, Higgins, JPT. Risk-of-bias VISualization (robvis): An R package and Shiny web app for visualizing risk-of-bias assessments. Res Syn Meth. 2020; 1-7) was used for development of traffic light plots and weighted bar plots for risk of bias. The literature search conducted produced 41,909 articles. Among these 19,076 were noted as duplicates and were excluded in the initial analysis; 22,833 manuscripts were thus screened after deduplication. Abstracts, case studies, reports, editorials, viewpoints, cross-sectional studies, cohort studies, case-control studies, case series, and letters to the editor/correspondence manuscripts (n = 22,745) were additionally excluded. A total of 88 full-text articles were assessed for eligibility. An in-depth evaluation and analysis further excluded 82 articles from the analysis quality assessment based on inclusion and exclusion criteria. Six RCTs were finally assessed regarding the prevention of CAUTIs and were ultimately included in the systematic review. The primary causative agents involved in the CAUTIs were found to be mainly Gram-negative bacteria such as Escherichia coli, Pseudomonas aeruginosa, and Enterococcus faecalis. The risk factors noted for the development of these CAUTIs ranged from urethral trauma, overdistention of the bladder, prolonged catheterization, to improper handling of the urine bag. No significant advantage was noted between the use of medicated and non-medicated standard Foley catheters. The aseptic technique and indications followed for the catheterization play a vital role in the prevention of CAUTIs, and more cognizance thereof will aid in the reduction of the development of CAUTIs.

Reduction of Urinary Tract Infection in Pediatric Surgical Patients Using NSQIP-P and Quality Improvement Methodology

BACKGROUND

Hospital-acquired urinary tract infections (UTIs) have a detrimental effect on patients, families, and hospital resources. The Sydney Children's Hospital Network (SCHN) participates in the NSQIP-Pediatric (NSQIP-P) to monitor postoperative complications. NSQIP-P data revealed that the median UTI rate at SCHN was 1.75% in 2019, 3.5 times higher than the NSQIP-P target rate of 0.5%. Over three quarters of the NSQIP-P identified patients with UTI also had a urinary catheterization performed intraoperatively. A quality improvement project was conducted between mid-2018 and 2021 to minimize catheter-associated UTIs (CAUTIs) at SCHN.

STUDY DESIGN

NSQIP-P samples include pediatric (younger than 18 years) surgical patients from an 8-day cycle operative log. NSQIP-P data are statistically analyzed by the American College of Surgeons and provide biannual internationally benchmarked reports. The project used clinical redesign methodology with a 6-phase process for quality improvement projects.

RESULTS

The objectives of the project were to reduce urinary catheter duration of use, educate parents or carers, and improve catheter care and insertion technique by health staff. The duration of a urinary catheter in situ reduced from a median of 4.5 to 3 days from 2017 to 2021. The median NSQIP-P UTI rate at SCHN was reduced by 47.4% from 1.75% in 2019 to 0.9% in 2022.

CONCLUSIONS

A multifactorial approach in quality improvement has been shown to be an effective strategy to reduce UTI rates at SCHN, and patient outcomes were improved within a 3-year timeframe. Although this project has reduced UTI rates at SCHN, there remain opportunities for further improvement.

Urinary Tract Infection Diagnostic and Management Considerations in People with Spinal Cord Injury and Neurogenic Bladder

Urinary tract infections (UTIs) are common complications in people with neurogenic bladder. Prevention, diagnosis, and treatment are challenging for several reasons, including a high prevalence of asymptomatic bacteriuria and catheter use, frequent ambiguous nonlocalizing signs and symptoms, increased risk for complications and difficult-to-treat pathogens, and a lack of effective preventative methods. Current research aims to improve elicitation and evaluation of signs and symptoms, implement algorithms to avoid urine cultures in asymptomatic patients and use appropriate antibiotics for UTI, and identify novel effective prevention methods.

Is There Any Benefit to the Use of Antibiotics with Indwelling Catheters after Urologic Surgery in Adults

Antibiotic stewardship in urologic reconstruction is critically important, as many patients will require indwelling catheters for days to weeks following surgery and thus are at risk of both developing catheter-associated urinary tract infections (CAUTI) as well as multi-drug resistant (MDR) uropathogens. Accordingly, limiting antibiotic use, when safe, should help reduce antibiotic resistance and the prevalence of MDR organisms. However, there is significant heterogeneity in how antibiotics are prescribed to patients who need indwelling urethral catheters post-operatively. We performed a literature review to determine if there are benefits in the use of antibiotics for various clinical scenarios that require post-operative indwelling catheters for greater than 24 h. In general, for patients undergoing prostatectomy, transurethral resection of the prostate, and/or urethroplasty, antibiotic administration may be limited without increased risk of CAUTI. However, more work is needed to identify optimal antibiotic regimens for these and alternative urologic procedures, whether certain sub-populations benefit from longer courses of antibiotics, and effective non-antibiotic or non-systemic therapies.

Definitions of Urinary Tract Infection Used in Interventional Studies Involving Neurourological Patients-A Systematic Review

CONTEXT

Neurourological patients often encounter bacteriuria without any symptoms or may experience symptoms suspicious of urinary tract infections (UTIs). However, there is a lack of guidelines that unequivocally state the definition of UTIs in this specific patient group.

OBJECTIVE

To present all used definitions of UTIs in neurourological patients.

EVIDENCE ACQUISITION

This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Studies were identified by electronic search of Medline, Embase, Cochrane controlled trials databases, and clinicaltrial.gov without a time limitation (last search September 2020) and by screening of reference lists and reviews. The occurrences of the various UTI definitions were counted and the frequencies calculated.

EVIDENCE SYNTHESIS

After screening 7164 abstracts, we included 32 studies enrolling a total of 8488 patients with a neurourological disorder who took part in an interventional clinical study. UTI definitions were heterogeneous. The concordance to predefined definitions was low.

CONCLUSIONS

Interventional clinical studies rarely report specific definitions for UTIs, and both clinical and laboratory criteria used are heterogeneous. A generally accepted UTI definition for neurourological patients is urgently needed.

PATIENT SUMMARY

Patients suffering from neurological disorders often experience symptoms in their lower urinary tract that resemble urinary tract infections. Furthermore, they can have positive urine cultures without symptoms (the so-called asymptomatic bacteriuria). However, clinical studies rarely report specific definitions for urinary tract infections, and when it is done, they are heterogeneous. A generally accepted urinary tract infection definition for neurourological patients is urgently needed. TAKE  HOME MESSAGE: Interventional clinical studies on neurourological patients rarely report specific definitions for urinary tract infections (UTIs), and both clinical and laboratory criteria used are heterogeneous. A generally accepted UTI definition for neurourological patients is urgently needed.

Catheter-Associated Urinary Infections and Consequences of Using Coated versus Non-Coated Urethral Catheters-Outcomes of a Systematic Review and Meta-Analysis of Randomized Trials

Coated urethral catheters were introduced in clinical practice to reduce the risk of catheter-acquired urinary tract infection (CAUTI). We aimed to systematically review the incidence of CAUTI and adverse effects in randomized clinical trials of patients requiring indwelling bladder catheterization by comparing coated vs. non-coated catheters. This review was performed according to the 2020 PRISMA framework. The incidence of CAUTI and catheter-related adverse events was evaluated using the Cochran−Mantel−Haenszel method with a random-effects model and reported as the risk ratio (RR), 95% CI, and p-values. Significance was set at p < 0.05 and a 95% CI. Twelve studies including 36,783 patients were included for meta-analysis. There was no significant difference in the CAUTI rate between coated and non-coated catheters (RR 0.87 95% CI 0.75−1.00, p = 0.06). Subgroup analysis demonstrated that the risk of CAUTI was significantly lower in the coated group compared with the non-coated group among patients requiring long-term catheterization (>14 days) (RR 0.82 95% CI 0.68−0.99, p = 0.04). There was no difference between the two groups in the incidence of the need for catheter exchange or the incidence of lower urinary tract symptoms after catheter removal. The benefit of coated catheters in reducing CAUTI risk among patients requiring long-term catheterization should be balanced against the increased direct costs to health care systems when compared to non-coated catheters.

Control Release Coating for Urinary Catheters with Enhanced Released Profile for Sustained Antimicrobial Protection

Catheter-associated urinary tract infections (CAUTIs) are common and pose significant costs to healthcare systems. To date, this problem is largely unsolved as commercially available antimicrobial catheters are still lacking in functionality and performance. A prior study by Lim et al. ( Biotechnol. Bioeng. 2018, 115 (8), 2000-2012) reported the development of a novel anhydrous polycaprolactone (PCL) polymer formulation with controlled-release functionality for antimicrobial peptides. In this follow-up study, we developed an improved antimicrobial peptide (AMP)-impregnated poly(ethylene glycol) (PEG)-polycaprolactone (PCL) anhydrous polymer coating for enhanced sustained controlled-release functionality to provide catheters with effective antimicrobial properties. Varying the ratio of PEG and PEG-PCL copolymers resulted in polymers with different morphologies, consequently affecting the AMP release profiles. The optimal coating, formulated with 10% (w/w) PEG-PCL in PCL, achieved a controlled AMP release rate of 31.65 ± 6.85 μg/mL daily for up to 19 days, with a moderate initial burst release. Such profile is desired for antimicrobial coating as the initial burst release acts as a sterilizer to kill the bacteria present in the urinary tract upon insertion, and the subsequent linear release functions as a prophylaxis to deter opportunistic microbial infections. As a proof-of-concept application, our optimized coating was then applied to a commercial silicone catheter for further antibacterial tests. Preliminary results revealed that our coated catheters outperformed commercial silver-based antimicrobial catheters in terms of antimicrobial performance and sustainability, lasting for 4 days. Application of the controlled-release coating also aids in retarding biofilm formation, showing a lower extent of biofilm formation at the end of seven inoculation cycles.

Intraluminal diamond-like carbon coating with anti-adhesion and anti-biofilm effects for uropathogens: A novel technology applicable to urinary catheters

OBJECTIVES

To examine anti-adhesion and anti-biofilm effects of a diamond-like carbon coating deposited via a novel technique on the inner surface of a thin silicon tube.

METHODS

Diamond-like carbon coatings were deposited into the lumen of a silicon tube with inner diameters of 2 mm. The surface of the diamond-like carbon was evaluated using physicochemical methods. We used three clinical isolates including green fluorescent protein-expressing Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus. We employed a continuous flow system for evaluation of both bacterial adhesion and biofilm formation. Bacterial adhesion assays consisted of counting the number of colony-forming units and visualization of adhered bacterial cells by scanning electron microscope to evaluate the diamond-like carbon-coated/uncoated samples. The biofilm structure was analyzed by confocal laser scanning microscopy on days 3, 5, 7 and 14 for green fluorescent protein-expressing Pseudomonas aeruginosa.

RESULTS

The smooth and carbon-rich structure of the intraluminal diamond-like carbon film remained unchanged after the experiments. The numbers of colony-forming units suggested lower adherence of green fluorescent protein-expressing Pseudomonas aeruginosa and Escherichia coli in the diamond-like carbon-coated samples compared with the uncoated samples. The scanning electron microscope images showed adhered green fluorescent protein-expressing Pseudomonas aeruginosa cells without formation of microcolonies on the diamond-like carbon-coated samples. Finally, biofilm formation on the diamond-like carbon-coated samples was lower until at least day 14 compared with the uncoated samples.

CONCLUSIONS

Intraluminal diamond-like carbon coating on a silicone tube has anti-adhesion and anti-biofilm effects. This technology can be applied to urinary catheters made from various materials.

Catheter-Associated Urinary Tract Infections in the Adult Patient Group: A Qualitative Systematic Review on the Adopted Preventative and Interventional Protocols From the Literature

Catheter-associated urinary tract infections (CA-UTIs) are among the most common nosocomial infections acquired by patients in health care settings. A significant risk factor for CA-UTIs is the duration of catheterization. To summarize the current strategies and interventions in reducing urinary tract infections associated with urinary catheters, use and the need for re-catheterization on the rate of CA-UTIs, we performed a systematic review. A rapid evidence analysis was carried out in the Medline (via Ovid) and the Cochrane Library for the periods of January 2005 till April 2021. The main inclusion criterion required to be included in this review was symptomatic CA-UTI in adults as a primary or secondary outcome in all the included studies. Only randomized trials and systematic reviews were included, reviewed, evaluated, and abstracted data from the 1145 articles that met the inclusion criteria. A total of 1145 articles were identified, of which 59 studies that met the inclusion criteria were selected. Studies of relevance to CA-UTIs were based on: duration of catheterization, indication for catheterization, catheter types, UTI prophylaxis, educational proposals and approaches, and mixed policies and interventions. The duration of catheterization is the contributing risk factor for CA-UTI incidence; longer-term catheterization should only be undertaken where needed indications. The indications for catheterization should be based on individual base to base cases. The evidence for systemic prophylaxis instead of when clinically indicated is still equivocal. However, antibiotic-impregnated catheters reduce the risk of symptomatic CA-UTIs and bacteriuria and are more cost-effective than other impregnated catheter types. Antibiotic resistance, potential side effects and increased healthcare costs are potential disadvantages of implementing antibiotic prophylaxis. Multiple interventions and measures such as reducing the number of catheters in place, removing catheters at their earliest, clinically appropriate time, reducing the number of unnecessary catheters inserted, decrease antibiotic administration unless clinically needed, raising more awareness and provide training of nursing personnel on the latest guidelines, can effectively lower the incidence of CA-UTIs.

Fragility Analysis of Statistically Significant Outcomes of Randomized Control Trials in Spine Surgery: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVES

The aim of this study was to assess the robustness of statistically significant outcomes from randomized control trials (RCTs) in spine surgery using Fragility Index (FI) which is a novel metric measuring the number of events upon which statistical significance of the outcome depends.

SUMMARY OF BACKGROUND DATA

Many trials in Spine surgery were characterized by fewer outcome events along with small sample size. FI helps us identify the robustness of the results from such studies with statistically significant dichotomous outcomes.

METHODS

We conducted independent and in duplicate, a systematic review of published RCTs in spine surgery from PubMed Central, Embase, and Cochrane Database. RCTs with 1:1 prospective study design and reporting statistically significant dichotomous primary or secondary outcomes were included. FI was calculated for each RCT and its correlation with various factors was analyzed.

RESULTS

Seventy trials met inclusion criteria with a median sample size of 133 (interquartile range [IQR]: 80-218) and median reported events per trial was 38 (IQR: 13-94). The median FI score was 2 (IQR: 0-5), which means if we switch two patients from nonevent to event, the statistical significance of the outcome is lost. The FI score was less than the number of patients lost to follow-up in 28 of 70 trials. The FI score was found to positively correlated with sample size (r = 0.431, P = 0.001), total number of outcome events (r = 0.305, P = 0.01) while negatively correlated with P value (r = -0.392, P = 0.001). Funding, journal impact-factor, risk of bias domains, and year of publication did not have a significant correlation.

CONCLUSION

Statistically significant dichotomous outcomes reported in spine surgery RCTs are more often fragile and outcomes of the patients lost to follow-up could have changed the significance of results and hence it needs caution before transcending their results into clinical application. The addition of FI in routine reporting of RCTs would guide readers on the robustness of the statistical significance of outcomes. RCTs with FI ≥5 without any patient lost to follow-up can be considered to have clinically robust results.Level of Evidence: 1.

A comparative study of experimental urinary catheters containing silver and zinc for biofilm inhibition

Both commercial and experimental antibacterial urinary catheters were investigated for their efficacy in preventing planktonic growth and biofilm formation of Escherichia Coli bacteria in a synthetic urine solution. Experimental antibacterial catheters having thin (<500 µm) dispersions of Ag, Ag/Ag₂O, or Zn/Ag₂O in polydimethylsiloxane (PDMS) binder all exhibited significant antimicrobial activity, outperforming traditional commercial antibacterial catheters. All experimental catheters prevented planktonic growth of bacteria and did not exhibit biofilm formation during a six-day test period using a colony forming unit (CFU) measurement method. On the other hand, the best performing commercial catheters demonstrated efficacy for only 3 days in planktonic growth tests and formed multiple bacterial colonies in CFU measurements. The Zn/Ag₂O/PDMS experimental catheter was the only catheter observed to produce hydrogen peroxide, a reactive oxygen species known to inhibit biofilm formation; lack of detectable hydrogen peroxide production by the Ag₂O/PDMS and Ag/Ag₂O/PDMS experimental catheters suggests that bactericidal action most likely arises from release of silver ions present in the PDMS coatings.

Effectiveness of silver alloy-coated silicone urinary catheters in patients with acute traumatic cervical spinal cord injury: Results of a quality improvement initiative

Patients with acute traumatic cervical spinal cord injury (ATCSCI) have an increased risk of catheter-associated urinary tract infection (CAUTI). The effectiveness of silver alloy-coated silicone urinary catheters (SACC) in preventing CAUTI in ATCSCI is unknown and was the objective of this study. We performed a quality improvement initiative in an attempt to reduce CAUTI in patients undergoing spine surgery at a single quaternary center. Prior to July 2015, all patients received a latex indwelling catheter (LIC). All patients with ATCSCI with limited hand function (AIS A,B, or C) received a SACC. Incidence of CAUTI, microbiology, duration of infection, antibiotic susceptibility, and catheter-associated adverse events were recorded prospectively. We studied 3081 consecutive patients over the three years, of whom 302 (9.8%) had ATCSCI; 63% of ATCSCI patients were ASIA Impairment Scale (AIS) A or B. The overall rate of CAUTI was 19% (585/3081), and was 38% (116/302) in patients with ATCSCI. Of 178 ATCSCI patients with LIC, 100 (56%) developed a CAUTI compared with 28 of 124 (23%) patients with SACC (p < 0.05). Poly-microbial and gram-positive infection was more common in LIC than in SACC (p < 0.05). Median duration of infection was 9 days in SACC group and 12 days in LIC group (p = 0.08). Resistance to trimethoprim (p < 0.001) and ciprofloxacin (p < 0.05) were more common in LIC group. There was no difference in catheter-associated adverse events or length of stay between the groups. This quality improvement initiative illustrates the effectiveness of antiseptic silver alloy-coated silicone urinary catheters in patients with ATCSCI. In our population, the use of SACC reduces the incidence and the complexity of CAUTI.

Role of noble metal-coated catheters for short-term urinary catheterization of adults: a meta-analysis

OBJECTIVE

To evaluate the efficacy of noble-metal coated catheters in reducing catheter-associated urinary tract infections (CAUTI) in adult patients requiring short term catheterization.

METHODS

An electronic literature search of PubMed, BioMed Central, Embase, Scopus, CENTRAL (Cochrane Central Register of Controlled Trials) and Google scholar was carried out from inception to 10th October 2019. Any prospective study or randomized controlled trial (RCT) on adult patients comparing noble-metal coated urinary catheters with any standard catheter and evaluating the incidence of CAUTI or bacteriuria was included.

RESULTS

A total of 13 studies were included in the systematic review. 12 were RCTs and one was a prospective cross-over trial. Catheters employed in the study group were grouped into two sub-groups: Silver alloy coated or Noble metal alloy-coated (Gold, Silver, and Palladium) catheters. Bacteriuria was the most commonly studied outcome variable across trials. Meta-analysis indicated that silver alloy-coated catheters (RR 0.63, 95%CI 0.44-0.90, P = 0.01; I2 = 72%) and noble metal alloy catheters (RR 0.58, 95%CI 0.41-0.81, P = 0.001; I2 = 0%) significantly reduce the risk of bacteriuria. Sub-group analysis based on the duration of catheterization demonstrated that silver alloy catheters reduce the risk of bacteriuria with >1week of catheterization (RR 0.46, 95%CI 0.26-0.81, P = 0.007; I2 = 63%). Symptomatic CAUTI was evaluated only in four studies with variable results. The quality of the included studies was not high.

CONCLUSIONS

Our review indicates that bacteriuria may be reduced with the use of noble metal-coated catheters during short-term catheterization of adults, however, the quality of evidence is not high. It is not clear if these catheters reduce the risk of symptomatic CAUTI. Further homogenous RCTs are needed to provide clarity.

Role of lipopolysaccharides and lipoteichoic acids on C-Chrysophsin-1 interactions with model Gram-positive and Gram-negative bacterial membranes

Antimicrobial peptides (AMPs) are attractive as biomaterial coatings because they have broad spectrum activity against different microbes, with a low likelihood of incurring antimicrobial resistance. Direct action against the bacterial membrane is the most common mechanism of action (MOA) of AMPs, with specific MOAs dependent on membrane composition, peptide concentration, and environmental factors that include temperature. Chrysophsin-1 (CHY1) is a broad spectrum salt-tolerant AMP that is derived from a marine fish. A cysteine modification was made to the peptide to facilitate attachment to a surface, such as a biomedical device. The authors used quartz crystal microbalance with dissipation monitoring to study how temperature (23 and 37 °C) and lipid composition influence the MOA of cysteine-modified peptide (C-CHY1) with model membranes comprised of supported lipid bilayers (SLBs). These two temperatures were used so that the authors could better understand the differences in behavior between typical lab temperatures and physiologic conditions. The authors created model membranes that mimicked properties of Gram-negative and Gram-positive bacteria in order to understand how the mechanisms might differ for different types of bacterial systems. SLB models of Gram-positive bacterial membranes were formed using combinations of phosphatidylcholine, phosphatidylglycerol (PG), and S. aureus-derived lipoteichoic acid (LTA). SLB models of Gram-negative bacterial membranes were formed using combinations of phosphatidylethanolamine (PE), PG, and E. coli-derived lipopolysaccharides (LPS). The molecules that distinguish Gram-positive and Gram-negative membranes (LTA and LPS) have the potential to alter the MOA of C-CHY1 with the SLBs. The authors' results showed that the MOA for the Gram-positive SLBs was not sensitive to temperature, but the LTA addition did have an effect. Specifically, similar trends in frequency and dissipation changes across all overtones were observed, and the same mechanistic trends were observed in the polar plots at 23 and 37 °C. However, when LTA was added, polar plots showed an association between C-CHY1 and LTA, leading to SLB saturation. This was demonstrated by significant changes in dissipation, while the frequency (mass) was not increasing after the saturation point. For the Gram-negative SLBs, the composition did not have a significant effect on MOA, but the authors saw more differences between the two temperatures studied. The authors believe this is due to the fact that the gel-liquid crystal transition temperature of PE is 25 °C, which means that the bilayer is more rigid at 23 °C, compared to temperatures above the transition point. At 23 °C, a significant energetic shift would be required to allow for additional AMP insertion. This could be seen in the polar plots, where there was a steep slope but there was very little mass addition. At 37 °C, the membrane is more fluid and there is less of an energetic requirement for insertion. Therefore, the authors observed greater mass addition and fewer changes in dissipation. A better understanding of C-CHY1 MOA using different SLB models will allow for the more rational design of future therapeutic solutions that make use of antimicrobial peptides, including those involving biomaterial coatings.

Outcome of Different Approaches to Reduce Urinary Tract Infection in Patients With Spinal Cord Lesions: A Systematic Review

Neurogenic bladder disorders are common among patients with spinal cord lesions, which often result in upper and lower urinary tract complications. Urinary tract infection has remained the most frequent type of infection in this population. Our aim is to review systematically the literature on the outcome of different intervention methods to reduce urinary tract infection incidence. A literature search was conducted in the database of Medline, PubMed, Embase, and Scopus. After screening 1559 articles, 42 were included in this review. The intervention methods can be categorized into the four following groups: (1) indwelling catheterization and intermittent catheterization, (2) medications, (3) surgery, and (4) others. Intermittent catheterization is still the most recommended treatment for persons with spinal cord lesions. Hydrophilic catheters are more suitable for adults than children because of complex handling. Bladder management with spontaneous voiding is initially considered for infants and toddlers with spina bifida. Antibiotics treatment should be based on the results of urine cultures. Shortening the course of antibiotics treatment can reduce its adverse effects but may increase urinary tract infection recurrence. Because botulinum toxin injections and bladder surgery can improve urodynamic function, both are conducive toward lowering urinary tract infection incidence.

Catheter-Associated Urinary Tract Infections in Adult Patients

BACKGROUND

Urinary tract infections are among the more common types of nosocomial infection in Germany and are associated with catheters in more than 60% of cases. With increasing rates of antibiotic resistance worldwide, it is essential to distinguish catheter-associated asymptomatic bacteriuria from catheter-associated urinary tract infection (CA-UTI).

METHODS

This review is based on publications from January 2000 to March 2019 that were retrieved by a selective search in Medline. Randomized clinical trials and systematic reviews in which the occurrence of CA-UTI in adult patients was a primary or secondary endpoint were included in the analysis. Two authors of this review, working independently, selected the publications and extracted the data.

RESULTS

508 studies were identified and 69 publications were selected for analysis by the prospectively defined criteria. The studies that were included dealt with the following topics: need for catheterization, duration of catheterization, type of catheter, infection prophylaxis, education programs, and multiple interventions. The duration of catheterization is a determinative risk factor for CA-UTI. The indications for catheterization should be carefully considered in each case, and the catheter should be left in place for the shortest possible time. The available data on antibiotic prophylaxis do not permit any definitive conclusion, but they do show a small benefit from antibiotic-impregnated catheters and from systemic antibiotic prophylaxis.

CONCLUSION

Various measures, including careful consideration of the indication for catheterization, leaving catheters in place for the shortest possible time, and the training of nursing personnel, can effectively lower the incidence of CA-UTI. The eous in some respects, and thus no recommendations can be given on certain questions relevant to CA-UTI.

QCM-D characterization of time-dependence of bacterial adhesion

Quartz crystal microbalance with dissipation monitoring (QCM-D) is becoming an increasingly popular technique that can be employed as part of experimental and modeling investigations of bacterial adhesion. The usefulness of QCM-D derives from this technique's ability to probe binding and interactions under dynamic conditions, in real time. Bacterial adhesion is an important first step in the formation of biofilms, the control of which is relevant to industries that include shipping, water purification, packaging, and biomedical devices. However, many questions remain unanswered in the bacterial adhesion process, despite extensive research in this area. With QCM-D, multiple variables affecting bacterial adhesion can be studied, including the roles of substrate composition, chemical modification, solution ionic strength, environmental temperature, shear conditions, and time. Recent studies demonstrate the utility of QCM-D in developing new bacterial adhesion models and studying different stages of biofilm formation. We provide a review of how QCM-D has been used to study bacterial adhesion at stages ranging from the first step of bacterial adhesion to mature biofilms, and how QCM-D studies are being used to promote the development of solutions to biofilm formation.

Medical Management of Neurogenic Bladder for Children and Adults: A Review

Neurogenic bladder is a chronic condition affecting patients of all ages with significant medical and quality of life implications. Goals of treatment consist of protection of the upper urinary tract and promotion of reliable urinary continence. Successful management involves medications and most often bladder drainage via clean intermittent catheterization. This article reviews current literature on medical management to achieve goals of treatment.

Spinal Cord Injury Creates Unique Challenges in Diagnosis and Management of Catheter-Associated Urinary Tract Infection

Background: Catheter-associated urinary tract infection (CAUTI) is associated with increased morbidity and mortality and influences the quality of life of patients with spinal cord injury (SCI). Objectives: This clinical review aims to highlight the unique surveillance, prevention, diagnosis, and management challenges of CAUTI in the SCI population. Methods: Narrative review of the current literature on catheter use in persons with SCI was conducted to determine gaps in knowledge and opportunities for improvement. Results: Surveillance of CAUTI is challenging in the SCI population as the ability to detect symptoms used to diagnose CAUTI (ie, suprapubic pain, dysuria) is impaired. In terms of prevention of CAUTI, current strategies refocus on appropriate catheter insertion and care and early removal of catheters, which is not always feasible for persons with SCI. Prophylactic antibiotics, nutraceuticals, and coated catheters show limited efficacy in infection prevention. Diagnosing CAUTI after SCI is challenging, often resulting in an overdiagnosis of CAUTI when truly asymptomatic bacteriuria exists. In the management of CAUTI in patients with SCI, the use of multiple antibiotics over time in an individual increases the rate of multidrug-resistant organisms; therefore, the exploration of novel non-antibiotic treatments is of importance. The patient experience should be at the center of all these efforts. Conclusion: Better diagnostic tools or biomarkers are needed to define true CAUTI in people with SCI. SCI-specific evidence to inform catheter management and CAUTI treatment guidelines is needed, with the goal to minimize catheter-related harm, reduce antibiotic resistance, and improve satisfaction and overall quality of life for SCI patients.

A tolerability and patient acceptability pilot study of a novel antimicrobial urinary catheter for long-term use

AIMS

We have developed a novel antimicrobial urinary catheter (AUC) impregnated with rifampicin, triclosan, and sparfloxacin and demonstrated that it has long-term (∼84 days) protection against bacterial colonization in vitro. This study aimed to assess the safety and patient acceptability of this device in long-term catheter users.

METHODS

Adults who use long term (>28 days) indwelling urinary catheters with capacity to consent were invited to receive the AUC at their next catheter change. The primary outcome measure was adverse events (AE) attributable to antimicrobial impregnation of the catheter. Secondary outcome measures included severity of related AEs, patient acceptability, early removal of the trial catheter, and degree of microbial colonization of trial catheters. Except for the last, outcomes were assessed by telephone interviews. Original and trial catheters were collected, and the lumens and balloons were separated and analyzed for microbiological colonization.

RESULTS

Thirty participants were recruited. Eighty four AEs were reported, and only one was rated as "probably" related to antimicrobial impregnation. The AE was mild and resolved within 48 h. A total of 82.14% of participants rated the catheter as no different or better than their usual catheter. Two participants chose to remove the AUC early due to it feeling shorter. There were significantly fewer bacterial isolates attached to the balloons of trial catheters compared to the matched original catheters.

CONCLUSIONS

The AUC has an advantageous safety profile and was acceptable to the majority of participants. Information gained from this trial will support a larger randomized controlled study of efficacy.

Diabetic foot infection: A critical complication

The number of people in the world with diabetes has nearly quadrupled in the past 40 years. Current data show that 25% of these diabetics will develop a foot ulcer in their lifetime and that the cost of care for a diabetic foot ulcer (DFU) is over twice that of any other chronic ulcer aetiology. Microbial biofilm has been linked to both wound chronicity and infection. Close to 1 in 2 diabetics with a DFU are predicted to go on to develop a diabetic foot infection (DFI). The majority of these DFIs have been found to evolve even before the diabetic individual has received an initial referral for expert DFU management. Of these infected DFUs, less than half have been shown to heal over the next year; many of these individuals will require costly hospitalisation, and current data show that far too many DFIs will require extremity amputation to achieve infection resolution. The development of an infection in a DFU is critical at least in part because paradigms of infection prevention and management are evolving. The effectiveness of our current practice standards is being challenged by a growing body of research related to the prevalence and recalcitrance of the microbes in biofilm to topical and systemic antimicrobials. This article will review the magnitude of current challenges related to DFI prevention and management along with what is currently considered to be standard of care. These ideas will be compared and contrasted with what is known about the biofilm phenotype; then, considerations to support progress towards the development of more cost-effective protocols of care are highlighted.