Written by Joshua Belfer
Spoon Feed
Urine dipstick testing is highly accurate for diagnosing UTI in febrile infants aged 2-6 months and may eliminate the need for initial laboratory urinalysis.
Because babies don’t have time to wait for the lab to run the UA
Accurately and quickly diagnosing UTIs in febrile infants while also minimizing overtesting and overtreatment is crucial to prevent complications and avoid unnecessary delays in treatment. While urine dipsticks are fast and accessible, there is a concern that young infants’ impaired urine concentrating ability may impact accuracy. Performance in older febrile infants had not been rigorously compared to lab urinalysis – until now.
This multicenter cross-sectional study evaluated whether urine dipstick testing accurately diagnoses urinary tract infections in febrile infants aged 2-6 months compared to laboratory urinalysis. Among 9,387 infants with a urine culture, 11% had a UTI. Dipstick testing (positive leukocyte esterase or nitrite) demonstrated higher sensitivity (90.2% vs 83.9%) and specificity (92.6% vs 87.0%) than urine microscopy (≥7 WBC/HPF). These findings suggest that point-of-care dipstick testing reliably identifies UTIs in this population, potentially streamlining clinical decision-making. This study included only infants who had a urine culture obtained, introducing potential selection bias, and results may not generalize to settings with different urine collection practices or patient populations.
How will this change my practice?
The practice of utilizing only a urine dipstick to initially diagnose a UTI (without a urinalysis) has been institution-dependent, but this study provides evidence that it is appropriate to initiate treatment without a formal UA. While a culture is still necessary to definitively diagnose a UTI, utilizing only a dipstick can help reduce the patient’s ED length of stay and reduce costs. The dipstick typically results in minutes (if not sooner), meaning once I obtain a urine sample from the infant, I can have an answer, give an antibiotic (for positive tests), and discharge within minutes, as opposed to the 30, 60, or 90 minutes it might take for a UA to result – happy patient, happy parent, happy doctor!
Source
Urine Dipstick for the Diagnosis of Urinary Tract Infection in Febrile Infants Aged 2 to 6 Months. Pediatrics. 2025 Apr 1;155(4):e2024068671. doi: 10.1542/peds.2024-068671. PMID: 40122108
