Abstract Book - 26th ESPU Congress, Joint Meeting with ICCS + SPU + AAP/SOU + AAPU + SFU

S8: OBSTRUCTION & HYDRONEPHROSIS

Moderators: Marc Cendron (USA), Pedro Lopez-Pereira (Spain)

ESPU Meeting on Thursday 15, October 2015, 11:32 - 12:16

11:32 - 11:37

S8-1

(LO)

★

PREDICTING CHRONIC KIDNEY DISEASE IN INFANTS AND YOUNG CHILDREN

WITH POSTERIOR URETHRAL VALVES: OBJECTIVE ANALYSIS OF INITIAL

ULTRASOUND KIDNEY CHARACTERISTICS AND VALIDATION OF PARENCHYMA

AREA AS FORECASTERS OF RENAL RESERVE

Paul BOWLIN

, Rakan ODEH

, Damien NOONE

, Fahad ALYAMI

, Luis BRAGA

and Armando LORENZO

1) The Hospital for Sick Children, Pediatric Urology, Toronto, CANADA - 2) The Hospital for Sick Children, Pediatric

Nephrology, Toronto, CANADA - 3) McMaster University, Department of Surgery and McMaster Pediatric Surgery

Research Collaborative, Hamilton, CANADA

PURPOSE

Uropathy secondary to posterior urethral valves (PUV) is a common cause of chronic kidney disease (CKD) in

children/adolescents. There is paucity of early markers to help prognosticate an individual child’s risk of renal

deterioration. Based on recent data estimating renal mass by measuring the renal parenchymal area (RPA), we

hypothesized that early measurement of both quantity (RPA) and quality (renal echogenicity [RE] and cortico-medullary

differentiation [CMD]) of the total renal mass could help predict future function. Herein we sought to validate existing

RPA data and evaluate RE and CMD as forecasters of renal reserve.

MATERIAL AND METHODS

Initial postnatal US images from serial children diagnosed with PUV at a tertiary care center were analyzed using NIH

sponsored image-processing software. Echogenicity was objectively measured as a ratio relative to the adjacent

liver/spleen. CMD was calculated by indexing the pixel density of identically-sized areas of the renal cortex and medulla

from a single representative US image. The primary outcome, renal function at last follow up, was determined based on

serum creatinine and dichotomized following need for renal replacement therapy at last follow-up (dialysis or renal

transplantation: CKDV).

RESULTS

75 patients were evaluated; 16 of these had progressively developed CKDV at a mean follow-up of 64.2+/-38.9 months.

Mean RPA was 21.41 cm

in Non-CKDV vs 16cm

in CKDV groups (p<0.001). Mean CMD was 1.77 in Non-CKDV vs 1.21

in CKDV (p<0.001). Bilateral echogenic kidneys were significantly associated with development of CKDV (p=0.004).

These findings remained statistically significant on multivariable and time to event analyses. CMD index showed a trend

that reflects deterioration as measured by serum creatinine at last follow-up.

CONCLUSIONS

RPA, CMD, and RE, have prognostic value for determining risk of CKDV in PUV patients. These data are promising for

developing prognostic tools to help risk stratify patients, counsel parents, and plan monitoring protocols for children with

PUV.