Incidence of urinary tract infections in infants with antenatally diagnosed hydronephrosis-A retrospective single center study

Objective: To evaluate the incidence of urinary tract infections (UTIs) in infants with antenatal hydronephrosis (AHN). Materials and Methods: A cohort of AHN patients admitted to our institution between 2003 and 2013 were identified. Altogether 192 patients with nonrefluxing hydronephrosis (HN, n = 135), nonrefluxing hydroureteronephrosis (HUN, n = 21), or vesicoureteral reflux (VUR, n = 36) were identified. Patients with complex anomalies or neonatal decompression of the urinary tract were excluded. Information about UTIs diagnosed among the AHN patients was collected and compared with data from 58 controls. Results: During the median follow-up time of 2.6 (0.3-11.2) years, 24 (13%) patients (15 (10%) males and 9 (19%) females) and 2 (3%) controls experienced at least one UTI (p = 0.033). Eighteen (69%) UTIs were febrile. The males had the first UTI at significantly younger age than the females (0.3, 0.0-1.7 years vs. 1.0, 0.4-4.8 years, p = 0.010). UTI was detected in 15 (63%) patients with grade 4-5 VUR, in 8 (6%) patients with HN, and in one (5%) patient with HUN (p-values < 0.001, 0.726 and > 0.999 against the controls). None of the patients with grade = 3 VUR had UTI. Fifty-eight percent of the patients with UTI were on antimicrobial prophylaxis. In five (12%) cases UTI appeared within one week after voiding cystourethrography (VCUG). Conclusions: Infants with AHN and grade 4-5 VUR had the highest risk of UTI. UTIs tented to be more common in females than in males; however, males experienced UTI at younger age than females. VCUG caused UTI in 2.3% in our material. (C) 2017 Elsevier Inc. All rights reserved.