Lessening Urine Contamination in Children and Adolescents

Abstract

Source: Hoover AC, Segal RS, Zimmerman MB, et al. Urine trouble: reducing midstream clean catch urine contamination among children 3–17 years old. Pediatrics. 2021;148(2):e2020049787. doi:10.1542/peds.2020-049787Investigators from the University of Iowa, Iowa City, IA, conducted a study to assess the effectiveness of a quality improvement intervention designed to reduce the rate of bacterial contamination in urine specimens collected by a clean catch technique. The intervention was developed by a multidisciplinary team, including representatives from inpatient and outpatient units and the emergency department at the University of Iowa Stead Family Children’s Hospital. A specific process was followed in developing the intervention, which included literature reviews, observations from various stakeholders, and an iterative approach in which different interventions were assessed. The final quality improvement intervention included use of a cleansing towelette with 0.13% benzalkonium chloride for urethral meatus cleansing, a set of instructions for obtaining a clean catch sample provided to the patient or caregiver, emphasis on a mid-stream collection, avoiding the insertion of dipsticks in the urine sample sent for culture, clarification that samples should arrive at the microbiology laboratory within 30 minutes of collection or be refrigerated, and real-time tracking of contamination rates.The primary study outcome was change in urine contamination rates before (April 2016 to September 2017) and after (April 2018 to September 2018) hospital-wide implementation of the quality improvement intervention. Sustainability of the intervention was assessed by assessing contamination rates during consecutive 12-month periods in 2018–2019 and 2019–2020. A standard definition for classifying a urine culture as contaminated was used, and all cultures were processed by a single microbiology laboratory. Chi-square tests were used to compare contamination rates prior to and after implementation of the quality improvement bundle; subgroup analyses, including by age groups (3–9, 10–15 and 16–17 years) and sex also were conducted.During the pre-intervention phase a total of 912 clean-catch urine cultures were obtained, of which 416 (45.6%) were contaminated. In the 6-month period following implementation of the quality improvement intervention, the contamination rate in 233 urine cultures was 30.9% (decrease of 14.7 percentage points; 95% CI, -21.5, -8.0). There were statistically significant decreases in contamination rates in female patients (52.7% to 40.1%, -12.6 percentage points; 95% CI, -21.1, -4.1) and in children 3-9 years old and those 10–15 years old; no significant decreases were observed in male patients or in those 16–17 years old. Although there was a significant decrease (-7.3 percentage points; 95% CI, -11.6, -2.9) in contamination rates throughout the entire follow-up period, rates increased to 38.3% during the 2018–2019 period and to 42.9% in 2019–2020 period.The authors conclude that implementation of a quality improvement intervention reduced the rates of bacterial contamination in clean catch urine cultures.Dr Sanchez-Kazi has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.The diagnosis of urinary tract infection is dependent on the quality of urine specimen collected. To lessen bacterial contamination in febrile infants and children up to 2 years of age, the AAP recommends that urine culture be obtained by urethral catheterization or suprapubic aspiration. (See AAP Grand Rounds. 2018:39[4]:39.)1 In toilet-trained children and adolescents, several clinical guidelines recommend obtaining urine by mid-stream clean catch with adequate cleaning of the urogenital area.2,3 In the current quality improvement study initiated by residents, bacterial contamination rate decreased with the combination of education regarding proper cleaning prior to urine collection and timely processing of the urine specimen. Similar interventions including development of specific digital apps were utilized in previous studies but with conflicting results.4,5Within 2 years of observation, the contamination rate slowly increased, albeit lower than the pre-intervention period. It is extremely helpful that the authors extended the period of observation to determine sustainability and, more importantly, to assess the role of performance bias in clinical intervention studies. The results of the current study reinforce the need for frequent review and constant reinforcement of the protocol with medical personnel and patients or caregivers in order to reduce the need for repeated urine testing, leading to conservation of both time and resources. It is interesting to note that the urine contamination rate obtained by catheterization is higher in the current study than in other reports.6Proper cleaning of the urogenital area and timely processing of collected urine specimens reduce bacterial contamination in toilet-trained children and in adolescents.