ירחון החברה הישראלית לפדיאטריה אמבולטורית (חיפ"א) גיליון 2018-2

27 The reliability of urinalysis in febrile young infants Urinalysis is a useful tool in diagnosing and excluding urinary tract infection (UTI). In very young infants (<60 days old), the utility of urinalysis as been questioned and usually not relied upon. In the February issue of Pediatrics, Tzimenotas, et al evaluated the accuracy of urinalysis in these infants. Performing a secondary analysis across 26 emergency departments, they evaluated over 4000 infants who were evaluated for sepsis, 7 percent of which had urinay tract infections. When compared to the results urine cultures, urinalysis demonstrated remarkable sensitivity of 0.94 and a specificity of 0.91. Looking at individual parameters, results varied with leukocyte esterase having a sensitivity of 0.92 and nitrates, 0.38. Whereas the study demonstrates utility of LE, there are several limitations. First, these results were from specimens obtained from catheterization (mostly) or suprapubic aspiration (SPA). No bagged specimens were used. Urine culture cut-offs of 50,000 CFUs resulted in better results (as above) as opposed to a 10,000 CFUs (UA sensitivity of 0.87). Additionally, only patients who had blood cultures obtained were reviewed. Patients with significant underlying conditions, prematurity, clinical sepsis and recent antibiotic use were excluded. As most physicians in the community rely on bagged specimens, this study has limited utility. However, take into consideration that with recent success of Prevnar and HiB vaccinations we are seeing far less serious bacterial infection (SBI) in the neonatal age and that most of the SBIs at this age are UTIs. With improved reliance on urinalysis (in catheterized or SPA specimens at the very least), we may be able to reduce the number of ER referrals for febrile infants at this age. Bottom line: Urinalysis from catheterized specimens are accurate in diagnosing UTIs in febrile very young infants. References: 1. Tzimenatos, L, et al. Accuracy of the Urinalysis for Urinary Tract Infection in Febrile Infants 60 Days and Younger. Pediatrics 2018;141(2):e20173068. 2. Schroeder AR, at al. Diagnostic accuracy of the urinalysis for urinary tract infection in infants, 3 months of age. Pediatrics 2015;135(6):965–971 3. Glissmeyer EW, Korgenski EK, Wilkes J, et al. Dipstick screening for urinary tract infection in febrile infants. Pediatrics. 2014;133(5):e1121–7 4. Arshad M, Seed PC. Urinary Tract Infections in the Infant. Clinics in perinatology. 2015;42(1):17- vii. doi:10.1016/j.clp.2014.10.003.