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Functional bladder capacity and urine osmolality in children with primary monosymptomatic nocturnal enuresis

Agata Korzeniecka-Kozerska1, Walentyna Zoch-Zwierz, Anna Wasilewska

  • 1I Department of Pediatrics, Medical University of Bialystok, 15-724 Bialystok, Poland. agatakozerska@poczta.onet.pl

Scandinavian Journal of Urology and Nephrology
|March 15, 2005
PubMed

Insights

Day-time bladder capacity increases with age in children with primary monosymptomatic nocturnal enuresis. Nocturnal urine osmolality is not dependent on age or sex in these patients.

Area of Science:

  • Pediatric Urology
  • Nephrology
  • Sleep Medicine

Background:

  • Primary monosymptomatic nocturnal enuresis (PMNE) is common in children.
  • Understanding functional day-time bladder capacity (DBC) and urine osmolality is crucial for managing PMNE.

Purpose of the Study:

  • To evaluate functional day-time bladder capacity (DBC) and urine osmolality in children with PMNE.
  • To determine the influence of age and sex on these parameters.

Main Methods:

  • A cohort of 263 children with PMNE was divided into two age groups (5-9 years and 10-15 years).
  • Functional DBC was measured as the largest daily void volume over four 24-hour periods.
  • Urine osmolality was assessed in the evening, at night, and in the morning.

Main Results:

  • Functional DBC was significantly higher in older children (10-15 years) compared to younger children (5-9 years).
  • No significant differences in DBC or nocturnal urine osmolality were observed between sexes.
  • No correlation was found between DBC and urine osmolality.

Conclusions:

  • Functional DBC in children with PMNE increases with age.
  • No age or sex dependency was found for mean nocturnal urine osmolality.
  • These findings contribute to understanding the pathophysiology of PMNE.
Abstract

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