The relationship between early renal status, and the resolution of vesico-ureteric reflux and bladder function at 16 months

Objective To examine, in infants presenting with vesicoureteric reflux (VUR ). the relationship between the presence of initial renal abnormalities wit h the outcome of VUR and bladder function at 16 months of age. Patients and methods The study group comprised 40 infants (32 boys) present ing consecutively (29 after prenatal detection) with VUR grade III or great er (bilateral in 29) on the initial micturating cystogram (median age 8 wee ks). The initial presence of abnormal kidneys was determined from isotopic renography and/or ultrasonography. These data were correlated with the outc ome of VUR, from direct isotope cystography, and bladder function assessed by natural filling urodynamics, examined at age 16 months (mean 16.4 months , SD 2.1). Results Three groups were identified. Group 1 (eight boys and six girls) ha d normal kidneys bilaterally; initially grade III VUR was common, At 16 mon ths bladder function was normal in 10 children and none had VUR (complete r esolution). Group 2 (14 boys and two girls) had unilateral renal abnormalit ies; initially VUR was predominantly grade IV or grade V. At 16 months blad der function was normal in eight children and VUR resolved in eight, five o f these with normal bladder function. Group 3 (10 boys) had bilateral renal abnormalities. Initially grade V VUR predominated: at 16 months the bladde r function was normal in only one, and in the rest the emptying dynamics we re abnormal. All 10 boys had persisting VUR (no resolution). Conclusions In infants with moderate or severe VUR, resolution at 16 months old is associated with normal kidneys in a similar proportion of boys and girls. Resolution also correlates well with normal bladder function. Presen tation in infancy with bilateral abnormal kidneys, associated with severe V UR in boys, is a poor prognostic sign for the early outcome of VUR and for bladder function.