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The use of urinary osmolality to evaluate postoperative renal function in children with ureteropelvic junction

Eduardo Luis Pérez-Etchepare Figueroa1, Teresa Moraleda Mesa2, Raquel Angélica Hernández Rodríguez1

  • 1Pediatric Surgery Department, Nuestra Señora de Candelaria University Hospital, Hospital Universitario Nuestra Señora de Candelaria (Santa Cruz de Tenerife), Carretera del Rosario 145, Santa Cruz de Tenerife, CP 38010, Spain.

Journal of Pediatric Urology
|July 10, 2021
PubMed

Insights

Maximum urinary osmolality after desmopressin administration (DDAVP) effectively detects renal dysfunction in children with ureteropelvic junction obstruction (UPJO). This sensitive marker aids in post-surgical follow-up, outperforming other renal function tests.

Area of Science:

  • Pediatric Nephrology
  • Urology
  • Diagnostic Imaging

Background:

  • Ureteropelvic junction obstruction (UPJO) is a common congenital anomaly.
  • Diuretic renography is standard for assessing UPJO, but sensitive markers for renal dysfunction are needed.
  • Desmopressin administration (DDAVP) can be used to assess maximum urinary osmolality (UOsm).

Purpose of the Study:

  • To evaluate the utility of maximum urinary osmolality (UOsm) after desmopressin administration (DDAVP) in detecting renal dysfunction in children with UPJO.
  • To assess the effectiveness of UOsm in the follow-up of pediatric UPJO patients post-surgery.

Main Methods:

  • A longitudinal study involving 56 children diagnosed with UPJO.
  • Quantification of maximum urinary osmolality (UOsm) at diagnosis and post-surgery (6-18 months) in 41 children.
  • Analysis of renal function markers including creatinine, albumin/creatinine ratio, NAG/creatinine ratio, and split renal function.

Main Results:

  • At diagnosis, 64% of UPJO patients showed abnormal UOsm after DDAVP; this decreased to 53% post-surgery.
  • Abnormalities in creatinine, albumin/Cr, and NAG/Cr ratios were noted in a subset of patients, with improvement post-surgery.
  • No significant correlation was found between UOsm and other functional/morphological parameters from ultrasound or renography.

Conclusions:

  • Maximum urinary osmolality (UOsm) after DDAVP is the most sensitive parameter for detecting renal dysfunction in children with UPJO.
  • UOsm is a valuable tool for monitoring renal function in UPJO patients after surgical intervention.
  • UOsm offers a more reliable assessment of renal function compared to other tested parameters in pediatric UPJO.
Abstract

Keywords:
Basic kidney function testRenal function testUreteropelvic junction obstructionUrinary NAGUrinary albuminUrinary osmolality

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