ESPU Congress 2018 - Abstract Book

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.