Background: Accurate diagnosis of urinary tract infection (UTI) in febrile infants requires valid urine samples. While invasive methods like urethral catheterization (CATH) have been standard, there is increased use of clean-catch (CC) methods due to their non-invasiveness. However, controversy remains regarding whether the CC technique yields an unacceptably high contamination rate compared to invasive collection methods. Objective: To compare the prevalence of contaminated cultures collected by CC vs. CATH in infants younger than 12 months. A secondary aim was to describe the contamination rate for each method stratified by patient age ( < 3, < 6, and < 12 months). Design/Methods: A systematic review and meta-analysis was conducted, describing the prevalence of contaminated urine culture collected by CC and CATH in infants younger than 12 months. A three-part search strategy was performed: 1) A systematic search of bibliographic databases; 2) Manual review of selected studies’ references; and 3) Review of proceedings from major pediatric congresses (2024–2025) to identify unpublished research. Data were extracted from published articles when available or by contacting the corresponding authors. Study quality was assessed using the Cochrane Risk of Bias Tool (for RCTs) and the 14-item NIH Quality Assessment Tool (for observational studies). The primary outcome was estimated using a random-effects meta-analysis with 95% confidence intervals (CI). Furthermore, as not all the studies included patients with urine cultures collected by both methods, a meta-analysis of cumulative rates (meta-analysis of proportions) was performed by analyzing separately the contamination rate of urine cultures in each technique. Data inclusion continues, results are provisional. Results: From 677 records, 75 full-text studies were reviewed, and 19 were included in the meta-analysis. For infants under 12 months, the CC method had a 18.4% (CI95% 12.4– 25.3) contamination rate, while CATH had a 7.8% (CI95% 4.0 - 12.7) contamination rate. Figure 1 shows the effect of the method of urine collection on the rate of culture contamination. Table 1 presents contamination rates by method and patient age.
Conclusion(s): Our meta-analysis confirms that, in infants under 12 months, clean-catch urine collection has a significantly higher contamination rate than urethral catheterization at all age strata analyzed. These findings underscore the need to balance contamination risk and invasiveness when selecting urine collection methods in clinical practice.
Figure 1. Forest plot showing the effect of the method of urine collection on the rate of culture contamination. Blue squares represent the point estimates of the odds ratio of each study, with 95% CI indicated by horizontal bars. Green diamond represents the summary estimate from the pooled studies with 95% CI Figure 1.pdf(Note: CATH, urethral catheterization; CC, clean-catch; CI, confidence interval)
Table 1. Contamination rate by method and patient age. Table 1.pdf(Note: CATH, urethral catheterization; CC, clean-catch; CI, confidence interval)
