Features of Nephrogenic Diabetes Insipidus

 

Clinical findings:

(1) polyuria

(2) polydipsia

(3) dehydration

(4) altered mental status progressing to coma (encephalopathy)

(5) seizures

(6) lethargy and weakness

 

Laboratory findings:

(1) dilute urine (osmolality < 250 mOsm per kg water)

(2) serum hypernatremia

(3) serum hyperosmolality (> 292 mOsm per kg water)

(4) serum ADH normal to elevated

Parameters	Central DI	Nephrogenic DI
serum ADH	low	normal to elevated
response to subcutaneous vasopressin or desmopressin	clinical response	no response

 

A patient with nephrogenic diabetes responds to:

(1) discontinuation of cause if identifiable

(2) salt restriction

(3) thiazide diuretics