I. Definition
A. Polyuric syndrome that results from a deficiency of or insensitivity to antidiuretic hormone (ADH), causing volume depletion related to inability to concentrate urine
B. Three types of diebetes insipidus (DI)
1. Central (neurogenic)—deficiency of ADH production or release
2. Nephrogenic—renal insensitivity to ADH
3. Psychogenic
II. Incidence/predisposing factors
A. Central—due to damage to the hypothalamus or the pituitary that results in a deficiency of ADH production or release
1. Idiopathic
2. Trauma
3. More commonly seen with neurosurgical patients
a. Brain tumors
b. Intracranial hemorrhage
c. Aneurysms
d. Pituitary tumors
4. Infections
a. Meningitis
b. Tuberculosis
c. Syphilis
5. Anoxic encephalopathy
6. Vasopressinase-induced
a. Seen in the puerperium and during last trimester of pregnancy
b. Associated with preeclampsia or liver dysfunction
C. Psychogenic—Refer to specialist.
III. Subjective/physical examination findings
A. May be physically asymptomatic (with central DI) or
B. Changes in level of consciousness
C. Thirst (extreme) is present with cravings for ice water; the patient may report 5 to 20 L/day of fluid intake.
