End 4 - Glucocorticoids And Cushing Syndrome Flashcards
What does Cortisol do?
Maintain BP: upregulating alpha1 receptors. Increase gluconeogenesis, lipolysis, proteolysis. Suppresses inflammation and immune system.
Why will steroids elevate WBC count when you first give it?
Because it is moving a lot of the WBC into the blood stream.
What is the difference b/w Primary, secondary, and terciary adrenal insufficiency?
Primary: Adrenal glands are knocked out. Secondary: Pituitary is knocked out. Tertiary: hypothalamus where the CRH is made is knocked out.
How do Glucocorticoids reduce inflammation?
They inhibit cyclooxygenase and phospholipase A2.
What is the primary cause of Cushing syndrome?
Chronic glucocorticoid use.
What are the side effects of Chronic Glucocorticoid use?
Cushing syndrome: Easy bruising, striae, acne, buffalo hump, moon facies. Diabetes. Osteoporosis. Glaucoma. Peptic Ulcers. Neuropsychiatric issues (insomnia, psychosis). Tertiary adrenal insuff (due to the negative feedback) and subsequent atrophy of adrenal cortex.
What are the symptoms of Cushing syndrome?
[BAM, CUSHINGOID] Buffalo hump. Amenorrhea. Moon facies. Crazy. Ulcers. Skin changes. Infection. Necrosis of femoral head. Glaucoma. Osteoporosis. Immunosuppresion. Diabetes.
What are the causes of Cushing syndrome?
Exogenous steroid use. Cushing disease (ACTH-producing pituitary adenoma). Ectopic ACTH production (small cell lung cancer). Cortisol-producing adrenal adenoma.
What is the difference b/w Cushing syndrome and Cushing disease?
Cushing syndrome are the usual symptoms only. Cushing disease is when there is an ACTH-producing pituitary adenoma.
What test can be performed to identify the different causes of Cushing syndrome? What are the elements of it?
The Dexamethasone suppression test; give a low dose 1mg of it and check cortisol levels the next day. For high dose give 8 mg of it in various injections and check cortisol levels the next day.
How will the dexamethasone test of low dose and high dose look for an ACTH-producing pituitary tumor?
Low dose: the cortisol will remain high. High dose: the cortisol will decrease.
How will the dexamethasone test of low dose and high dose look for in ectopic ACTH production tumor?
High cortisol in both low dose and high dose.
How will the dexamethasone test of low dose and high dose look for Cortisol-producing tumor?
High cortisol in both low dose and high dose.
How can we differentiate b/w Ectopic ACTH production vs Cortisol-production since you cannot tell them apart using dexamethasone suppression test?
The ectopic ACTH producing will have high ACTH. The cortisol-producing tumor will have low ACTH.
An adult man w/ elevated serum cortisol levels and signs of Cushing syndrome undergoes a dexamethasone suppression test. 1 mg of dexamethasone does not decrease cortisol levels, but 8 mg does. What is the diagnosis?
ACTH producing pituitary tumor (Cushing disease).
