title: Mild hydronephrosis in newborns and infants: can ultrasound predict the presence of vesicoureteral reflux.
abstract: The objective of our study was to determine the significance of mild hydronephrosis in newborns and infants as an indicator of vesicoureteral reflux (VUR). The voiding cystourethrography (VCUG) of 573 patients aged 0-18 months with mild, sonographically detected hydronephrosis were reviewed for VUR. Patients with secondary reflux or anomalies making an exact reflux grading impossible were excluded. Normal kidneys, contralateral to hydronephrotic ones, were included. Each kidney was considered separately, forming a total of 1,146 renal units. Mild hydronephrosis was defined as an anteroposterior diameter of the renal pelvis of 0.5-1.5 cm without caliectasis. The International Grading System was used to grade VUR. Seven hundred and thirty-six kidneys had mild hydronephrosis. VUR occurred in 189 out of 736 (25.7%) of these kidneys, and in 108 out of 410 (26.3%) non-distended kidneys, contralateral to hydronephrotic ones (p=0.806). No statistical differences in the frequency of VUR and dilatation were found between the subgroups of patients with and without infection, except for a higher grade of reflux in the group with infection. The frequency of VUR in mildly dilated kidneys was not significantly different from that in non-distended ones. There was a poor correlation between VUR and mild hydronephrosis. The latter should not be considered in itself an indication for VCUG in asymptomatic neonates and infants.
authors.affiliation: Division of Paediatric Radiology, Department of Radiology, Hospital Universitario La Paz, Paseo Castellana, 261, Madrid, 28046, Spain.
authors.forename: Teresa
authors.initials: T
authors.lastname: Berrocal
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Pinilla
authors.forename: Julia
authors.initials: J
authors.lastname: Gutiérrez
authors.forename: Consuelo
authors.initials: C
authors.lastname: Prieto
authors.forename: Luis
authors.initials: L
authors.lastname: de Pablo
authors.forename: María-Luisa
authors.initials: ML
authors.lastname: Del Hoyo
mesh_terms: D005260:Female; D006801:Humans; D006869:Hydronephrosis / Q000000981:diagnostic imaging* / Q000209:etiology*; D007223:Infant; D007231:Infant, Newborn; D007668:Kidney / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D014463:Ultrasonography; D014551:Urinary Tract / Q000000981:diagnostic imaging / Q000503:physiopathology; D014552:Urinary Tract Infections / Q000175:diagnosis / Q000209:etiology; D014718:Vesico-Ureteral Reflux / Q000150:complications* / Q000000981:diagnostic imaging