Hyperadrenocorticism (Cushing’s Disease)

What is Cushing’s caused by

Excessive circulating cortisol produced by the adrenal gland

Spontaneous disease can be pituitary or adrenal mass

Can be iatrogenically caused b/c pts are on oral or topical steroids

Between a pituitary or adrenal mass, which one is the cause of majority of Cushing’s cases

Pituitary dependent - there is a pituitary mass which causes excess ACTH (adrenocorticotropic hormone), negative feedback from cortisol doesn’t work, and cortisol keeps increasing

Clinical signs of hyperadrenocorticism (Cushing’s)

Increase urination and drinking (polyuria/polydipsia)

Pot-bellied appearance - too much cortisol can weaken abdominal muscles and fat redistributes to abdomen

Hair loss

calcinosis cutis

Excessive panting

What are lab findings that show a pt has Cushing’s

Elevated ALP (alkaline phosphatase - also checks liver stuff)

+ / - proteinuria

Can be prone to UTI

How to diagnose Cushing’s in dogs

ACTH stimulation test or Low-Dose Dexmethasone suppression test

Low-Dose Dex suppression test can differentiate a pituitary cause from an adrenal cause

What are the treatments to Cushing’s

Trilostane (Vetoryl) - Works by inhibiting steroid synthesis (which should decrease cortisol)

Milotane (Lysodren) - Destroys a part of the adrenal cortex to prevent cortisol production → can cause more side effects and cause permanent changes that could lead to hypoadrenocorticism

What are clinical signs of Cushing’s in horses

All the previous symptoms in dogs plus

Hirsutism - abnormal long and wavy hair coat)