Feline Pituitary & Adrenal Diseases Flashcards
What are the 3 most common causes of insulin resistance in diabetic cats?
- hyperadrenocorticism - pituitary or adrenal
- acromegaly - pituitary
- hyperthyroidism
What is the most common signalment associated with hyperadrenocorticism in cats?
~10 y/o - no breed or sex predisposition known
What are the 4 most common clinical signs associated with hyperadrenocorticism in cats? What else is seen?
- PU/PD
- abdominal enlargement
- polyphagia
- skin atropy
- muscle wasting, weight loss/gain
- alopecia, skin fragility (can tear off)
- unkempt hair coat
- plantigrade stance
- hepatomegaly
What are 3 common laboratory findings in cats with hyperadrenocorticism?
- hyperglycemia - DM common
- hypercholesterolemia
- increased ALT > ALP —> cats lack cALP
What is most commonly found on UA in cats with hyperadrenocorticism?
- glucosuria
- proteinuria
- minimally concentrated USG
What testing is preferred for diagnosing hyperadrenocorticism in cats? What is typically avoided?
LDDST
ACTH stim - poor sensitivity in cats (only 1/3 are +)
What medical treatment is recommended in cats with hyperadrenocorticism? When in surgery recommended?
Trilostane
if ADH
How are pituitary macroadenomas causing Cushing’s in cats typically managed?
- tumor control with radiation therapy
- clinical control with Trilostane
How does presentation in cats with Cushing’s compare with dogs? Clinical pathology?
- panting is rare in cats
- alopecia is more mild and less common
- skin can tear spontaneously
80% of cats will be diabetic (10% in dogs)
What is the most common cause of acromegaly?
GH-secreting macroadenoma
- hyperplasia can rarely occur
- also causes insulin resistance - 30-50% of cats
What signalment is most commonly associated with acromegaly?
older (10 y/o) neutered males
- no breed predisposition
What are the 4 most common presentations in cats with acromegaly?
- insulin-resistant diabetes (30-50%)
- stridor
- heart failure
- neurologic signs - increased tumor size
What is the most common clinical sign associated with acromegaly? What is also seen?
weight gain
- PU/PD
- polyphagia
- weight loss
- stridor
- stiffness
- lameness
What is commonly seen on physical exam in cats with acromegaly?
- abdominal organomegaly
- broad facial features
- clubbed paws
- prognathia inferior
- widening interdental spaces
- enlarged tongue
- murmur associated with cardiac hypertrophy
Acromegaly:
broad features tend to develop slowly and go unnoticed by owners
What 2 diagnostics are used in cats that possibly have acromegaly?
- IGF-1 levels - will be pronounced, possibly slightly elevated in poorly controlled diabetics (hard to measure GH)
- CT/MRI - confirms tumor
What 2 non-medical treatments are available for cats with acromegaly?
- hypophysectomy to remove tumor
- radiation therapy - less invasive
What 2 medical therapies are available for cats with acromegaly?
- Pasireotide - somatostatin analog that blocks GH production ($$$)
- Cabergoline - dopamine receptor agonist
What are the 3 effects of hypersomatotropism?
- arthritis
- stridor
- heart failure
How can the diabetes in cases of cats with acromegaly and insulin resistance be controlled?
higher doses of insulin —> sudden hypoglycemia possible
What is the prognosis of acromegaly like?
- short-term with definitive tx = guarded to poor
- long-term = poor
- survival = 4-60 months
What are the 2 most common causes of primary hyperaldosteronism in cats? Why is it commonly under-diagnosed?
- adrenal tumor
- idiopathic hyperplasia
can look like CKD
What is the most common signalment associated with feline hyperaldosteronism?
older (11 y/o) cats with no sex or breed predisposition
What are 5 common clinical signs associated with feline hyperaldosteronism? What are some non-specific signs?
- cervical ventroflexion (hypokalemia)
- weakness/collapse (hypokalemia)
- dysphagia
- ataxia
- ocular hypertension and blindness
anorexia, restlessness, weight loss
What is most commonly seen on physical exam in cats with hyperaldosteronism?
- hypertension
- bilateral retinal detachment
- heart murmur
What 3 things in clinical pathology are seen in cats with primary hyperaldosteronism?
- hypokalemia
- azotemia - increased BUN/creatinine
- increased CK - myopathy
What 3 things are diagnostic of primary hyperaldosteronism in cats?
- hypokalemia
- elevated aldosterone on plasma aldosterone concentrations (extremely high)
- ultrasound showing adrenal tumors and bilateral enlargement
What surgical treatment is recommended for primary hyperaldosteronism in cats?
unilateral adrenalectomy
What 3 medical treatments are recommended in cats with primary hyperaldosteronism?
- Spironolactone (potassium-sparing!)
- Amlodipine for hypertension
- K supplementation with IV KCl or oral potassium gluconate
make sure to treat underlying disease!
