62
29
th
CONGRESS OF THE ESPU
S6: OBSTRUCTION
& HYDRONEPHROSIS 1
Moderators: Josef Oswald (Austria), Darius Bagli (Canada)
ESPU Meeting on Thursday 12, April 2018, 09:34–10:20
09:34–09:39
S6-1 (LO)
★
SUPRANORMAL RENAL FUNCTION IN UNILATERAL
HYDRONEPHROTIC PAEDIATRIC KIDNEYS: PREOPERATIVE
AND POSTOPERATIVE PECULIARITIES
Oriol MARTIN-SOLE, Sonia PEREZ-BERTOLEZ, Jenny ARBOLEDA,
Andrea SORIA‑GONDEK, Francisco Javier VICARIO LATORRE and
Luis GARCIA-APARICIO
Hospital Sant Joan de Déu, Paediatric Urology Division, Paediatric Surgery Department., Esplugues De Llobregat,
SPAIN
PURPOSE
The meaning of supranormal (SN) differential renal function (DRF) on unilateral hydronephrotic
kidneys remains controversial. Our objective was to compare preoperative and postoperative
characteristics in SN DRF patients with non-SN DRF patients.
MATERIAL AND METHODS
Our prospectively collected pyeloplasty database was reviewed. Patients operated between
2012 and 2017 were included (n=91). We excluded 13 patients with bilateral hydronephrosis,
vesicoureteral reflux, redo pyeloplasty or solitary kidney. SN-group was formed by the 9 patients
(11.5 %) who had preoperative supranormal DRF defined as DRF ≥ 55 %. Remaining 69 patients
formed the non-SN group. The following parameters were collected: age, sex, anteroposterior
renal pelvis diameter, SFU hydronephrosis grade, laterality, aetiology, ultrasound measured kidney
volume and renal pelvis volume and pre and postoperative DRF.
RESULTS
The preoperative anteroposterior pelvis diameter (27.4 mm vs. 35.4 mm, p=0.026) and the ratio
between preoperative pelvis volume and kidney volume (0.34 vs. 0.93, p<0.0025) were higher in
SN group. Preoperative pelvis diameter was a good predictor of supranormal DRF, with an AUC of
the ROC curve of 0.804 (95 %CI: 0,707–0,902). A pelvis diameter ≥30 mm predicts a supranormal
DRF with 88.9 % of sensitivity and 73.9 % of specificity. Pelvis volume/kidney volume ratio was an
independent risk factor on multiple regression analysis (p=0.037). There was a greater postopera-
tive loss of function in SN-group compared to non-SN group (-0.3 % vs -6.4 %, p=0.0049).
CONCLUSIONS
Patients with supranormal DRF had larger renal pelvis, higher pelvis volume/kidney volume ratio and
function decreased more after pyeloplasty. This suggest that preoperative DRF was overestimated,
questioning the role of preoperative function as the main parameter to indicate surgical procedure.