Endocrine disorders: Diabetes Insipidus

Question 1

Diabetes insipidus is caused by -?

Answer 1

Decrease in ADH/ Vasopressin (Central DI)

Decrease in renal receptors for ADH/ Vasopressin or an inability of renal receptors to respond to ADH/ Vasopressin (Nephrogenic DI)

Question 2

What disease processes are associated with secondary nephrogenic diabetes insipidus?

Answer 2

Hypercalcemia, hypokalemia, pyelonephritis, pyometra, PSS, liver insufficiency, hypoadrenocorticism (common in dogs), and hyperthyroidism (common in cats)

Question 3

How do you go about diagnosing diabetes insipidus?

Answer 3

Ruling out all other causes for polyuria and polydipsia, evaluating the serum biochemistry (look at Ca, K, BUN, Na, Glu), urinalysis and culture, and performing a Modified Water Deprivation Test (test whether the patient will be able to concentrate their urine when moderately dehydrated)

Question 4

What protocols are commonly used for treatment for diabetes insipidus?

Answer 4

CDI = Desmopressin, or NDI = Thiazides, low sodium diet

Other options include no medications, maintaining free access to water, being kept in conditions to prevent dehydration, and being allowed to urinate outside