Hospital-acquired Urinary Tract Infections in Neonatal ICU Patients: Is Voiding Cystourethrogram Necessary?

To evaluate the radiographic findings of neonatal intensive care unit (NICU) patients diagnosed with hospital-acquired urinary tract infection (UTI).

Children with no preexisting genitourinary anomalies undergoing a voiding cystourethrogram (VCUG) for culture-documented UTI during NICU admission were identified. Demographics, microbiology results, and imaging findings were evaluated.

A total of 147 NICU patients underwent VCUG during the study period. Of these, the indication for VCUG was UTI in 58 children. Neonates diagnosed with UTI were born at a mean gestational age of 28 3/7 ± 4 3/7 weeks, and underwent VCUG at a mean of age of 70.3 ± 42 days. Urine culture grew Enterococcus in 32 (55.2%), Enterobacter in 6 (10.3%), coagulase negative staphylococcus in 6 (10.3%), Escherichia coli in 5 (8.7%), and other in 9 infants (15.5%). All patients underwent a retroperitoneal ultrasound, which was read as normal in 31 patients (53.4%). Fourteen children (24.1%) diagnosed with UTI were found to have vesicoureteral reflux on VCUG. On univariate analysis, no patient characteristics were associated with VCUG positivity. On multivariate analysis, the effect of age at VCUG differed by renal-bladder ultrasound results. Patients with an abnormal ultrasound were 3.6 (95% confidence interval, 1.39-9.24) times more likely to have a positive VCUG for every 1 month increase in age.

Ultrasound anomalies are common in NICU patients diagnosed with UTI. The effect of age at VCUG differed by ultrasound result; the probability of vesicoureteral reflux in infants with sonographic abnormalities and UTI increases with age.