Objective: To identify clinical predictors associated with urinary tract infections (UTI) in patients in a referral neonatal intensive care unit (NICU).
Study design: We performed a nested case control study of all NICU patients with urine cultures obtained as part of late-onset sepsis evaluations from January 1, 2007 through December 31, 2007 (N=266). Clinical factors and laboratory results were compared between subjects with positive urine cultures (cases, N= 27) and randomly selected subjects with negative cultures (controls, N= 54).
Results: Cases were significantly older than controls at the time of urine culture (75 days vs. 29 days, p=0.003). Maximal peripheral white blood cell (WBC) count and C-reactive protein (CRP) did not differ between cases and controls. Only 24% of cases had a simultaneously positive blood culture. In multivariable analysis, only increased chronological age was statistically associated with a positive culture (OR 3.02, 95% CI 1.09, 8.39).
Conclusion: Limited clinical factors exist to identify NICU patients at increased risk for UTI. Peripheral WBC count and CRP do not help discriminate between patients with and without UTI. Clinicians should evaluate chronologically older NICU patients for infection like other young infants, including a urine culture, to adequately identify potential sources of infection.
Keywords: infant; neonate; prematurity; sepsis; “urinary tract infection”.