Of note, VUR also appears to be associated with a variable degree of renal dysplasia that is unrelated to infection. Indeed, both VUR and renal dysplasia could be expected to result from an abnormally caudal position of the ureteric bud on the mesonephric duct (see Plate 2-1) because this arrangement would cause both (1) suboptimal interaction between the ureteric bud and metanephric mesenchyme, as well as (2) a short intramural course for the ureter.

PRESENTATION AND DIAGNOSIS

VUR is generally first suspected when prenatal ultrasound reveals hydronephrosis or when a child developsa UTI. Among infants, further workup is indicated if a repeat postnatal ultrasound reveals persistent hydronephrosis. Among children, further workup is indicated if a male child has a UTI, a female child less than 5 years of age has a UTI, or a female child of any age has a febrile UTI.