Midstream Clean-Catch Urine Culture Obtained by Stimulation Technique versus Catheter Specimen Urine Culture for Urinary Tract Infections in Newborns: A Paired Comparison of Urine Collection Methods

Abstract

Objective: The group of Herreros Fernández developed a new, safe, quick, and successful technique for collecting midstream clean-catch urine(MS-CCU) in newborns based on bladder stimulation and lumbar paravertebral massage maneuvers. The purpose of this study was to compare the contamination rates of catheter specimen urine (CSU) and MS-CCU by a lumbar/sacral stimulation technique in newborns. Materials and Methods: Full-term newborns ranging in age from 2 to 28 days who needed an investigation for a presumed urinary tract infection (UTI) were included in the study. Two samples, MS-CCU by lumbar/sacral stimulation technique and CSU, were collected consecutively for each patient. Suitable samples were obtained from 90 patients. Results: The contamination rate in MS-CCU cultures (n = 24/90, 26.66%) was higher than in CSU cultures (n = 9/90, 10%), and the difference was statistically significant (p = 0.039). Thirteen patients had UTI according to both samples (14.14%). In urine analysis, while there was no statistically significant difference in bacteriuria (p = 0.61) and nitrite positivity (p = 0.14) between patients with and without UTI, pyuria (p = 0.01) and leukocyte esterase positivity (p = 0.01) were higher in patients with UTI, and the difference was statistically significant. Conclusion: The contamination rate in MS-CCU cultures was two and a half times greater than in the CSU culture samples. Thus, MS-CCU cannot replace the catheter for the diagnosis of UTI.

Catheter-Obtained Urine Culture Contamination Among Young Infants: A Prospective Cohort Study

“…In most previous studies, the reported contamination rate was lower, but the study design, definition of a positive urine culture, interpretation of low bacterial count, rate of circumcision, indication for the test, and the patient's age group were variable ( 4 , 9 – 11 , 13 , 15 ). In a retrospective study among older infants (2–24 months of age) in our pediatric department, we found a lower catheter-obtained urine culture contamination rate of 17%: 14% among boys and 18% among girls (unpublished data), emphasizing the higher contamination risk in very young infants.…”

“…No other study has showed such a low contamination rate. In two small prospective studies among neonates, the contamination rate of catheter-obtained urine culture was 10–22% ( 4 , 15 ). In agreement with our results, Wingerter et al showed the same contamination rate among infants <6 months, while using the same definition of contamination ( 12 ).…”

“…All urine culture collection methods for non-toilet-trained children have drawbacks. Collection bags and clean catch are non-invasive methods, but with extremely high contamination rates ( 2 , 9 – 11 , 15 ) and eventually a higher cost than other urine collection methods, taking into consideration equipment, staff time, and time occupying a hospital bed ( 5 ).…”

“…SPA, the gold-standard technique for obtaining a sterile urine culture with the lowest contamination rate, is considered unacceptably invasive and painful ( 3 ), with a relatively low success rate ( 4 , 5 ). Catheterization is less invasive and painful compared to SPA ( 3 ), its success rate is higher ( 4 , 5 ), and it has a lower contamination rate than collection bags and clean catch urine culture ( 5 , 9 – 11 , 15 ). Furthermore, catheterization is the most cost-effective urine collection method among non-toilet-trained children when compared to urine bag, clean catch, and SPA ( 5 ).…”