Circadian rhythm of water and solute excretion in nocturnal enuresis

Sevasti Karamaria; Lien Dossche; Vincent Delens; Eva Degraeuwe; Ann Raes; Reiner Mauel; Caroline Vande Walle; Karel Everaert; Johan Vande Walle

doi:10.1007/s00467-022-05645-8

Circadian rhythm of water and solute excretion in nocturnal enuresis

Pediatr Nephrol. 2023 Mar;38(3):771-779. doi: 10.1007/s00467-022-05645-8. Epub 2022 Jun 24.

Authors

Sevasti Karamaria^{1

2}, Lien Dossche^{1

2}, Vincent Delens¹, Eva Degraeuwe¹, Ann Raes^{1

2}, Reiner Mauel³, Caroline Vande Walle², Karel Everaert⁴, Johan Vande Walle^{5

6}

Affiliations

¹ Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium.
² Department of Pediatric Nephrology, Ghent University Hospital, Ghent, Belgium.
³ Department of Pediatric Intensive Care, Brussels University Hospital, Brussels, Belgium.
⁴ Department of Urology, Ghent University Hospital, Ghent, Belgium.
⁵ Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium. Johan.VandeWalle@uzgent.be.
⁶ Department of Pediatric Nephrology, Ghent University Hospital, Ghent, Belgium. Johan.VandeWalle@uzgent.be.

PMID: 35748940
DOI: 10.1007/s00467-022-05645-8

Abstract

Background: Nocturnal polyuria (NP) due to a suppressed vasopressin circadian rhythm is a well-documented pathogenetic mechanism in enuresis, mainly studied in monosymptomatic enuresis. A substantial percentage of patients do not respond to desmopressin. This suggests that NP may not only be related to vasopressin, but that other kidney components play a role. Solute handling and osmotic excretion have been investigated in the past, especially in refractory patients. Nevertheless, data in treatment-naïve populations with information on timing overnight are sparse. This study aims to investigate the diuresis and solute excretion in treatment-naïve patients with or without NP, with emphasis on circadian rhythms.

Methods: Retrospective analysis of 403 treatment-naïve children 5-18 years with severe enuresis (> 8 nights/2 weeks). Circadian rhythms were evaluated by a 24-h urine collection in 8 timed portions (4 day, 4 nighttime) at in-home settings. Urine volume, osmolality, and creatinine were measured. Patients were subdivided into three groups according to nocturnal diuresis (ND) and Expected Bladder Capacity (EBCage) ratio: (a) < 100%, (b) 100-129%, (c) > 130%.

Results: All groups maintained circadian rhythm for diuresis and diuresis rates. Patients with higher ND (100-129% and > 130% EBCage) had higher daytime volumes and less pronounced circadian rhythm. In the ND group > 130% EBCage, the ND rate was higher during the first night collection and osmotic excretion was significantly higher overnight.

Conclusions: Overall 24-h fluid intake (reflected by 24-h diuresis) and nutritional intake (24-h osmotic excretion) might play a role in enuresis. Increased diuresis rate early in the night can be important in some patients, whereas the total night volume can be important in others. A higher resolution version of the Graphical abstract is available as Supplementary Information.

Keywords: Children; Circadian rhythm; Diuresis rate; Enuresis; Osmotic excretion.

MeSH terms

Child
Circadian Rhythm
Deamino Arginine Vasopressin / therapeutic use
Humans
Nocturnal Enuresis*
Polyuria
Retrospective Studies
Vasopressins
Water

Substances

Deamino Arginine Vasopressin
Water
Vasopressins