Feline Hypercortisolism, Hypoadrenocorticism, and Hyperaldosteronism Flashcards
What is another term for Hyperaldosteronism?
Conns syndrome
What stimulates the release of Aldosterone, and where is aldosterone released from?
- Ang II, ↑ K+, corticotrophin
- Released from zona glomerulosa
Aldosterone is released from _______
A. Zona glomerulosa
B. Zona fasciculata
C. Zona reticularis
D. Adrenal medulla
A. Zona glomerulosa
What is the main action of aldosterone?
- Stimulates Na+ reabsorption and K+ and H+ excretion
- Upregulates endothelin, ACE, Ang II causing vasoconstriction
What are the main clinical signs in cats with Conns disease?
- Hypokalemia: Inappetance, weakness, cervical ventroflexion
- Hypertension: retinal detachment, ocular hemorrhage, kidney damage, cardiac hypertrophy
A cat is presenting with inappetance, weakness, and retinal detachment. How can Hyperaldosteronism be diagnosed?
- Check aldosterone levels (↑↑↑) and plasma renin activity (↓↓↓)
- AUS or CT to ID tumor
What is the treatment protocol for a patient with Hyperaldosteronism?
- 1st option is always medical management: Treat hypertension and hypokalemia
- Spironolactone
- Potassium supplementation
- Amlodipine
- Adrenalectomy if unilateral
What is the prognosis for cats with Conns disease?
(Hyperaldosteronism)
- 2-3 years regardless of surgery vs medical management, and regardless of neoplasia vs benign
What concurrent disease should always be investigated in a cat with hyperglycemia, PU/PD/PP, and uncontrolled diabetes mellitus?
HyperAdrenocorticism cats are almost always diabetic
A cat is presenting with thin skin, hair loss on the ventral abdomen, and calcinosis cutis. What are you suspect of?
A. Hyperaldosteronism
B. Hypercortisolism
C. Hypoadrenocortisolism
D. Congenital hypothyroidism
B. Hypercortisolism (HAC/Cushings)
What results would you expect from a ACTH stim test on a cat with Cushings disease?
(HAC)
- High normal baseline cortisol
- Supraelevated cortisol levels post ACTH
80% of cats with Hypercortisolism/Cushings have a mass localized to the ___________
Pituitary gland
(PDH most common in cats)
How do the adrenal glands appear on ultrasound in a cat with Hypercortisolism/Cushings?
- Cats usually have pituitary tumor (80%) secreting excess ACTH → bilateral hyperplasia of adrenal glands
- If adrenal tumor → 1 adrenal will be large, other will be atrophied
A cat with bilateral hyperplasia of the adrenal glands on ultrasound. Where is the tumor located?
pituitary tumor (80%) secreting excess ACTH → bilateral hyperplasia of adrenal glands → Cushings
What is the drug of choice for treating HAC in dogs and cats?
Trilostane
Which of the following is rarely seen in cats?
A. Hyperaldosteronism
B. Hypercortisolism
C. Primary hypoadrenocortisolism
D. Congenital hypothyroidism
C. Primary hypoadrenocortisolism
(idiopathic or secondary to neoplasia or trauma)
What is the main cause of Secondary hypoadrenocortisolism in dogs and cats?
Post admin of corticosteroids (iatrogenic addisons dz)
A cat presents with PU/PD, vomiting, weight loss, and waxing and waning non-specific clinical signs. He was treated 1 month ago at another vet for a skin infection. You run bloodwork and find the following changes.
- Lymphocytosis, hyperkalemia, hyponatremia
What is the most likely cause of these changes?
- Secondary hypoadrenocorticism (Addisons) post admin of steroids
(most likely cause of Addisons in cats is from steroids, primary hypoadrenocorticism is rare in cats)
alsoooo lack of stress leukogram in sick pet… Addisons!!!
What CBC change in a sick patient should trigger further testing for hypoadrenocorticism?
Lack of stress leukogram (lymphocytosis)
What are the top Ddx for hyperkalemia? (7)
- Hypoadrenocorticism / Addisons
- Insulin deficiency
- Hemolysis
- Urethral obstruction
- Urinary rupture
- AKI
- Acute acidosis
Why should ECG be performed in patients with suspect Addisons disease?
- Look for hyperkalemia
- Tented T waves, loss of P wave
What is the treatment protocol for patients with Hypoadrenocorticism / Addisons?
- IV fluids
- Adress hyperkalemia/dysrhythmias
- Glucocorticoids (Dexamethasone, Pred)
- Mineralocorticoids if typical Addisons (Fludrocortisone, DOCP)
How long does it take for cats and dogs treated for Hypoadrenocorticism / Addisons to respond?
Dogs: 1-2 days
Cats: 3-5 days (longer to respond)
Which of the following can cause tented T waves and loss of P waves on ECG? Select all that apply.
A. Hyperaldosteronism
B. Hypercortisolism
C. Hypoadrenocortisolism
D. Congenital hypothyroidism
C. Hypoadrenocortisolism (↑ K+)
Which of the following can result in hypotension?
A. Hyperaldosteronism
B. Hypercortisolism
C. Hypoadrenocortisolism
D. Hyperthyroidism
C. Hypoadrenocortisolism
What electrolyte changes occur in cats with Hyperaldosteronism?
↑ Na+ K+
