Purpose: When the standard cystogram does not show vesicoureteral reflux in children who have experienced febrile urinary tract infections (UTIs), clinical management is controversial. We postulated that vesicoureteral reflux accounts for such UTIs but is "occult." We tested this hypothesis by using a novel method, PIC cystography (Positioning the Instillation of Contrast at the ureteral orifice) at the time of cystoscopy.
Materials and methods: We performed PIC cystography with instillation of contrast medium at the ureteral orifice consecutively and prospectively in 57 children who underwent cystoscopy between November 1999 and February 2002 to evaluate febrile UTIs in 40 patients, dysfunctional voiding in 14 and hydronephrosis in 3. The control group (27 patients, 54 renal units) was used to assess the accuracy of PIC by comparing the results against those with the standard cystogram in children who did not have febrile infection and did not demonstrate vesicoureteral reflux (15 patients, 30 renal units), and in those who had febrile infection and vesicoureteral reflux (12 patients, 24 renal units). The study group (30 patients, 60 renal units) served to assess the incidence of "occult" vesicoureteral reflux in children who experienced febrile UTIs yet did not have vesicoureteral reflux on standard cystography.
Control group: In children without febrile UTIs all 30 ureteral orifices had a normal endoscopic appearance and no vesicoureteral reflux by PIC cystography. In children with febrile UTIs 15 ureteral orifices with known vesicoureteral reflux were lateral and/or patulous and demonstrated vesicoureteral reflux by PIC, 4 appeared normal and did not exhibit vesicoureteral reflux on standard cystography or by PIC, and 5 were lateral and/or patulous in appearance and did not display vesicoureteral reflux on standard cystography, but did show vesicoureteral reflux by PIC. These findings reveal that PIC cystography is 100% sensitive at demonstrating reflux already known by standard cystogram, is 87% specific as it showed reflux in 5 of 39 renal units not revealed by a standard cystogram and has an overall accuracy of 91%.
Study group: At cystoscopy all 30 children demonstrated an abnormal appearance of one or both ureteral orifices. PIC cystography showed vesicoureteral reflux in all 30 children (48 renal units, 12 unilateral and 18 bilateral). The remaining ureteral orifices (12), which appeared normal, did not permit vesicoureteral reflux. Children with vesicoureteral reflux by PIC were treated with antimicrobial prophylaxis (26) or ureteral reimplantation (4, 2 unilateral and 2 bilateral reimplantation) Postoperatively, these children did not experience a febrile UTI during followup (average 8 months).
Conclusions: PIC cystography is simple to perform using routinely available operating room equipment and does not artifactually induce vesicoureteral reflux. The incidence of "occult" vesicoureteral reflux in children who experience febrile UTIs without vesicoureteral reflux on standard cystography is 100% by PIC cystography. PIC cystography should be done when vesicoureteral reflux is suspected in children who experience febrile UTIs but do not exhibit reflux on standard cystography.