Internal Medicine

0521779407-15 CUNY1086/Karliner 0 521 77940 7 June 7, 2007 18:43

1042 Narcolepsy Nephrogenic Diabetes Insipidus

follow-up

■Depends on severity & response to treatment

complications and prognosis

Prognosis

■Cataplexy, hypnagogic hallucinations & sleep paralysis may improve

■Chronic disorder

NEPHROGENIC DIABETES INSIPIDUS

MICHEL BAUM, MD

history & physical

■Congenital nephrogenic DI – neonate with irritability, vomiting, con-

stipation, fever, failure to thrive

■Adults – polydipsia and polyuria

tests

■Neonates with hypernatremic dehydration with low Uosm – no

response to vasopressin

■Adults and children – Water deprivation test – inappropriately low

Uosm – no response to vasopressin

differential diagnosis

■X-linked – defect in vasopressin 2 receptor

■Autosomal dominant and recessive forms – defect in aquaporin 2

water channel

■Acquired – Li, demeclocycline, hypokalemia, hypercalcemia, sickle

cell disease, obstructive uropathy, medullary cystic disease, amyloi-

dosis, polycystic kidney disease, amphotericin

■Distinguish from other causes if polyuria/polydipsia: central dia-

betes insipidus, psychogenic polydipsia, and osmotic diuresis

management

■Allow free access to water.

■Inherited – thiazide diuretics to decrease GFR and filtered load of

water

■Acquired – treat primary cause

specific therapy

N/A