3. polyuria and polydipsia SDL

Question 1

what volume of urine per day must dogs and cats produce to be considered polyuric

Answer 1

anything exceeding 90ml/kg/day in dogs, anything exceeding 45ml/kg/day in cats

Question 2

can you list some factors external to the animal that would influence their water intake

Answer 2

• heat
• exercise
• fever
• cold climates
• vomiting/diarrhea

Question 3

what volume of urine per day must dogs and cats produce to be considered polyuric

Answer 3

more than 45 ml/kg/day in dogs
more than 40 ml/kg/day in cats

Question 4

name 2 stimuli that may cause ADH release

Answer 4

• increased blood osmolarity
• decrease in blood volume

Question 5

name causes of central diabetes insipidus

Answer 5

• inadequate ADH release from pituitary
• inadequate response within the kidney (kidney doesnt respond properly to ADH)

Question 6

name 2 endocrinopathies and a non-endocrine disease that cause secondary nephrogenic diabetes insipidus

Answer 6

Endocrinopathies: hyperadrenocorticism, hypoadrenocorticism, hyperthyroidism, hypercalcemia (PTH excess).
Non-endocrine diseases: Infections with certain bacteria that produce toxins that interfere with ADH action (pyelonephritis, pyometra).
Endocrine diseases with a different mechanism for PU/PD include hypoadrenocorticism (aldosterone deficiency, less Na and water resorption), hyperthyroidism (increased GFR)
Non-Endocrine diseases with a different mechanism for PU/PD include chronic renal disease (insufficient nephrons and osmotic diuresis), liver disease (reduced urea in blood and filtrate to contribute to a fully effective medullary concentration gradient)

Question 7

what would you expect to happen to the USG of a dog given synthetic ADH if it had central diabetes insipidus

Answer 7

increase

Question 8

what would you expect to happen to the USG of a dog given synthetic ADH if it had primary nephrogenic diabetes insipidus

Answer 8

no change