The effect of desmopressin on renal water and solute handling in desmopressin resistant monosymptomatic nocturnal enuresis.
OBJECTIVE
We sought to evaluate the effect of desmopressin on renal water and solute handling in children with monosymptomatic nocturnal enuresis and desmopressin resistant nocturnal polyuria compared to healthy controls.


METHODS
A total of 12 patients with enuresis and nocturnal polyuria, normal bladder reservoir function and no response to desmopressin, and 10 age matched controls were enrolled in the study. Children were admitted to the hospital for a 48-hour protocol comprising urine collections and blood sampling. Sodium and water intake was standardized. During the second night children received 40 mug intranasal desmopressin. Parameters characterizing the renal water and solute handling were measured and compared between baseline nights and nights with desmopressin.


RESULTS
Desmopressin markedly reduced nocturnal urine output in patients with enuresis, minimizing sodium, urea and overall solute excretion, despite the fact that these children were unresponsive to desmopressin at home. This effect on renal sodium handling was not mediated by atrial natriuretic peptide, angiotensin II, aldosterone or renin. Desmopressin did not influence urinary prostaglandin E(2) excretion. The antinatriuretic effect was seen only in patients with enuresis, and it was directly correlated with the reduction in urine output.


CONCLUSIONS
Children with nocturnal enuresis and nocturnal polyuria who do not exhibit adequate response to desmopressin at home seem to respond well to the agent at the clinic. The effect of desmopressin in children with enuresis seems largely dependent on reductions in the amount of sodium excreted. Sodium regulating hormones remained unaffected by desmopressin, indicating a possible direct effect of the agent on renal sodium handling.
Institute of Clinical Medicine, University of Aarhus, Aarhus University Hospital, Aarhus, Denmark. kostas.kamperis@ki.au.dk
Konstantinos
K
Kamperis
Søren
S
Rittig
Eva
E
Radvanska
Kaj A
KA
Jørgensen
Jens C
JC
Djurhuus
D000293:Adolescent; D000704:Analysis of Variance; D050034:Antidiuretic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D016022:Case-Control Studies; D002648:Child; D003894:Deamino Arginine Vasopressin / Q000009:adverse effects / Q000627:therapeutic use*; D004231:Diuresis / Q000187:drug effects / Q000502:physiology; D004351:Drug Resistance; D005500:Follow-Up Studies; D006801:Humans; D007677:Kidney Function Tests; D009318:Natriuresis / Q000187:drug effects; D053206:Nocturnal Enuresis / Q000175:diagnosis* / Q000188:drug therapy*; D009994:Osmolar Concentration; D011141:Polyuria / Q000188:drug therapy* / Q000503:physiopathology; D011336:Probability; D011453:Prostaglandins / Q000378:metabolism; D012016:Reference Values; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014563:Urodynamics; D014882:Water-Electrolyte Balance / Q000187:drug effects / Q000502:physiology
D050034:Antidiuretic Agents; D011453:Prostaglandins; D003894:Deamino Arginine Vasopressin