Clean intermittent catheterization (CIC) is associated with increased risk of urinary tract infections (UTI), urethral trauma, urethral stenosis, hematuria and pain. The first catheters developed were made of polyvinyl carbon (PVC). Different types of catheters have been developed to reduce these complications, such as those with hydrophilic coating.  The aim of the present study is to determine the rate of urinary tract infections in patients on CIC , who use hydrophilic coated versus uncoated catheters.

A systematic literature search was performed in OVID, Embase, Scopus, Web of Science, PubMed, and CENTRAL databases, to identify randomized controlled trials (RCTs) or randomized crossover trials, comparing UTI and hematuria rates in patients using  hydrophilic vs. non-hydrophilic catheters for CIC. Literature search was performed using a combination of keywords (MeSH terms and free text words) including (“Intermittent Urethral Catheterization” OR “Intermittent Urethral Catheterization” AND “Urinary Tract Infection” OR “Urinary Tract Infections” OR “Catheter-Related Infections”, “Urinary Catheters”).   The search aimed to identify all the papers reporting the results of RCTs and randomized crossover trials in full-length articles published in English and Spanish, with no time period limit.  

Two independent reviewers carried out the screening process for full-text articles. Once selected, information about study design, inclusion criteria, baseline patient characteristics, and outcomes was recorded.  Boths reviewers analyzed the studies, and decided if they should be included. Whenever there was no agreement, a third reviewer determined the inclusion of the study.  

The selected RCTs were evaluated for risk of bias by two reviewers individually, using the “Revised Cochrane risk-of-bias tool for randomized trials (RoB 2)”, according to the Cochrane Handbook for Systematic Reviews of Interventions (The Cochrane Collaboration, 2018).  When discrepancies were found in the risk-of-bias judgment, they were reviewed by a third author.  The results were expressed as risk ratio (RR) with 95% confidence interval (CI), under a random-effects model. Data were analyzed using Review Manager 5.4 software.

A total of 781 articles were found. After removing the duplicates, 574 articles were left for analysis. We carried out an initial screening by title and abstract, identifying 36 articles for complete review.  After applying the inclusion criteria, nine articles were selected to continue with the quality assessment. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) flow diagram is shown in Fig. 1. 

We identified seven RTCs and two cross-over studies that evaluated urinary tract infection or hematuria in hydrophilic or uncoated catheters users.  Nine studies with a total of 525 patients in CIC were analyzed. Overall, the use of hydrophilic catheters had a lower risk of UTIs compared to uncoated catheters (RR = 0.78; 95% CI: 0.62 – 0.97; I2: 37%).(Figure 2) Five of the studies included patients > 18 years showing a reduction  of UTIs  with the use of hydrophilic catheters (RR= 0.83; 95% CI: 0.74 - 0.93; I 2: 0%). There was no difference in UTI development when comparing single use uncoated vs hydrophilic catheter. However heterogeneity was high (RR = 0.77; 95% CI: 0.59 - 1.00; I2=57%).

Hydrophilic catheters had a UTI risk reduction of 17% when were compared to uncoated catheters (RR= 0.83; 95% CI: 0.74 - 0.93; I 2: 0%) in adults patients in CIC.  We did no find difference in UTI development when comparing single use uncoated vs hydrophilic catheter. However, in this analysis heterogeneity was high.

This meta-analysis verified a risk reduction of UTIs associated with the use of hydrophilic catheters for IC in adults.   Significative differences were not probe in terms of UTI in pediatrics population o hematuria overall.  Urethral trauma presence could not be meta‐analyzed due to lack of information reported. These result must be interpreted considering that heterogeneity was high between included studies, specially when we assessed hematuria.

Continence 2S2 (2022) 100356
DOI: 10.1016/j.cont.2022.100356