In this section
Diabetes insipidus (DI) is an uncommon condition with either
relative or absolute lack of anti-diuretic hormone (ADH) leading to
inability to concentrate the urine and subsequent
polyuria/polydypsia and potentially fluid and electrolyte
imbalance. This can be seen in a variety of conditions in the
paediatric population, most commonly in patients post neurosurgery
or with cerebral malformations.
Consideration should be given to:
Baseline investigations should include urea and electrolytes,
full ward test of urine and paired serum and urine osmolality.
Diabetes insipidus is present when the serum osmolality is
raised (>295 milliOsmol/kg) with inappropriately dilute urine
(urine osmolality <700 milliOsmol/kg). The serum sodium is often
elevated due to excess free water losses.
After assessment of level of dehydration and ongoing losses,
adequate rehydration therapy should be commenced. If the serum Na
is >150 mmol/L, rehydration should occur over 48 hours
(see hypernatraemia guideline).
If Na >170 mmol/L, contact ICU.
Discussion with the endocrinologist on call is advised
prior to the commencement of Desmopressintherapy
Desmopressin (DDAVP, trade name: Minirin(R)) acts on
the distal tubules and collecting ducts of the kidney to increase
water reabsorption, as a long acting analog of anti-diuretic
There are several formulations available:
Criteria for Desmopressin Administration
At RCH, Desmopressin should be administered by two accredited
Registered Nurses or parents, who are competent and confident,
ensuring the following 3 criteria have been achieved;
N.B. If desmopressin has been prescribed and the child does not
meet all 3 criteria then consult with senior staff (often Endocrine
/ Neurosurgery fellow or consultant) prior to administration of
desmopressin to prevent fluid overload and hyponatraemic
Inform the managing team (usually endocrine/specialties
registrar or endocrinologist on-call) if:
Desmopressin Administration Checklist (Children's Neuroscience