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Flashcards in Adrenal Disorders Deck (34)
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1
Q

Adrenocorticoids

  • these hormones are secreted by which layer of the adrenal gland?
  • what are the hormones?
A
  • hormones secreted by the adrenal cortex.

- Glucocorticoids, Mineralcorticoids, Androgens

2
Q

WHat is the main glucocorticoid hormone? Mineralcorticoid?

What is their function?

A
  • Glucocorticoid: cortisol, active in protecting against stress and in affecting protein and carb metab.
  • Mineralocorticoid: aldosterone, regulates the retention and excretion of fluids and electrolytes (Na and K) by the kidneys.
3
Q

What does the term corticosteroid refer to?

Why should you not stop steroid use abruptly?

A
  • it may refer to any of the steroid hormones secreted by the adrenal cortex OR steroid hormones manufactured synthetically for use as a drug.
  • chronic synthetic steroid use shut down the adrenals and cause atrophy, cannot immediately stop steroid use must gradually wean off because the adrenals take time to restore their baseline functions.
4
Q

Andrenal Sex hormones:

-function

A
  • little effect on sexual function
  • pubertal growth of body hair
  • DHEA?
5
Q

Which hormones are in the adrenal medulla?

What are the layers of the adrenal cortex and which hormones are associated with each layer?

A

-Medulla: E and NE

-Cortex:
Zona Glomerulosa: Aldosterone
Zona Fasciculata: Cortisol
Zona Reticularis: DHEA (androgen)

*GRF– get sweeter towards to center (Salt, Sugar, Sex)

6
Q

Adrenal Medulla
-made up of what type of cells?
-how does the adrenal recieve info to release these hormones?
-

A
  • made up of chromaffin cells, this is our main source of catecholamines (E and NE)
  • the adrenals recieve input from the Sympathetic Nervous System through preganglionic fibers originating in the thoracic spinal cord segments 5-11.
7
Q

Sympathetic System Functions, which hormones increase these effects? How long do they last?

A

“fight or flight”

  • increase heart rate and blood pressure
  • mobilize energy stores of the body
  • increase blood flow to skeletal muscles and heart while diverting flow from the skin and internal organs
  • dilation of bronchioles
  • dilation of pupils

-E and NE, when these hormones are secreted they have longer lasting effects (30mins or so) than if our SNS were just acting alone.

8
Q

Epinephrine and NE action on the:

  • Cardiovascular system
  • Respiratory System
  • Peripheral blood vessels/Skin
A

CV: E and NE bind to:
Beta 1 receptors on the heart:
-Inotropic action (strengthens contractility) of the myocardium
-Chronotropic action (increases rate) of the heart.

Beta 2 receptors on skeletal muscle:
- dilates vessels (increase blood flow)

Resp:
-bronchodilation by acting directly on bronchial smooth muscle, binding to Beta 2 receptors.

Skin:
-via alpha 1 receptors the arterioles are constricted in the skin to shunt blood to the vital organs.

Alpha 1= constrict smooth muscle and cutaneous blood velssels.

Beta 1= inotropic and chronotropic on heart

Beta 2= dilation of bronchial smooth muscle on lungs.

9
Q

Pheochromocytoma

  • what is this?
  • sx
  • tx of HTN
  • 90% of the time ____, _____, ____, ____.
  • Keys to dx
A
  • tumor of chromaffin cells of the adrenal medulla, releases excess E and NE which causes episodic* or sustained signs and sx such as palpitations, sweating, HA, fainting, htn emergencies, cold hands and feet
  • surgically remove the tumor, phenoxybenzomene and alpha blocker is given until surgical procedure.
  • in adrenal medulla, unilateral, not malignant, in adults.
  • Dx:
  • -episodic HTN, HA, palpitation, and sweating
  • -increased release of catecholamines in the urine during a period of HTN.
  • hunt for the source… CT of abdomen with focus on adrenal glands or MIR
10
Q

Adrenal Gland; Zona Glomerulosa

  • what hormone comes from here and whats its function?
  • whos the boss? (what dictates secretion of this hormone)
A
  • aldosterone: increases Na and water reabsorption by the kidneys AND increases the secretion of K. (indirectly regulating blood volume and pressure)
  • secretion dictated minimally by ACTH from AP but its is majorly dictated by changes in blood pressure. (renin-angiotensin-alodsterone system)
11
Q

What results when secretion of aldosterone is excessive?

What results with adrenal medulla insufficiency?

A
  • hypokalemia, hypernatremia, increased BP.

- decreased release of aldosterone, decreased blood pressure, hyponatremia, hyperkalemia.

12
Q

Primary Aldosteronism:

  • aka
  • what is this?
  • what are the effects of this?

-Tx

A
  • Conn’s Syndrome
  • a small tumor of the zona golmerulosa cells that secretes large amounts of aldosterone.

Effects:
-sodium conservation and potassium excretion.
Hypernatremia» increased volume» HTN.
Hypokalemia»muscle paralysis
-low renin: b/c the volume is already high enough so it doesnt need to increase blood volume.

  • Tx:
  • thin slice CT and surgical removal of adrenal adenoma.
13
Q

Zona Fasciculata:

  • what hormone is released here?
  • why might this hormone be excreted?
A

-cortisol

  • released in response to:
  • -infection, pain, hypoglycemia, trauma, hemorrhage, sleep, stress*
14
Q

Functions of Cortisol

A
  • stimulate glucose production by liver
  • promotes protein breakdown
  • mobilization of fatty acids
  • Immunologic and anti-inflammm effects. (blocks inflammation, suppresses immune system)
15
Q

Major Adverse Effects of excess cortisol

A
  • hyperglycemia
  • supresses immune system
  • decreased bone density
  • central nervous system and mental status effects
  • elevated BP (d/t hyperaldosteron)
  • stimulate gastric acid and pepsin production.
16
Q

Feedback mechanisms of Cortisol

A
  • Hypothalamus releases CRH to the AP. AP releases ACTH, ACTH acts on the adrenal cortex to seceret cortisol. Cortisole has negative feedback effects on AP and Hypothal.
  • cortisol increases gluconeogensis, protein metab, fat metab, and stabilizes lysosomes which relieves stress.
17
Q

Zona Reticularis

-what hormone is secreted here?

A

andorgens: DHEA and Androstendione

18
Q

What does “sweeter towards the center” mean?

A

Glomerulosa»Salt (mineralcort.)
Fasciculata»>Sugar (Glucocort.)
Reticularis»>Sex (Androgens)

19
Q

What are the cushings types? What is cushings sydrome?

A

Type 1: CUSHINGS DISEASE:excess ACTH coming from Pituitary tumor. (ACTH dependent)

Type 2: benign malignant adrenal tumor (ACTH independent)

Type 3: ectopic cushings, non-pituitary ACTH secreting tumor, SMALL CELL LUNG CANCER. (ACTH dependent)

Type 4: Iatrogenic from high steroid use. (ACTH independent)

Cushings Syndrome: is anytime you have inceased cortisol.

20
Q

WHat are the cushing symptoms?

A
  • extremity muscle wasting
  • round center/trunkal obesity
  • moon face
  • buffalo hump
21
Q

What lab test would confirm cushing syndrome along with clinical signs?

A
  • 24hr urinary free cortisol study

* most direct and reliable practical index of cortisol secretion.

22
Q

Cushings syndrome is most often seen from what?

A

-exogenous administration of glucocorticoids.

23
Q

After you collect urinary cortisol what tests need to be done next and why?

A

-need other test because the urinarly cortisol just tells you the patient has steroid excess.

Should get:

  • plasma ACTH (Midnight and 2am)
  • Abdominal CT (looking for adrenal mass)
  • MRI of the sella for pituitary tumor
24
Q

WHat is a Dexamethasone Suppression test? Why do we do this? What could the results be?

A
  • 1mg of dexamethasone orally in the evening…then serum cortisol determination at about 8am the next AM.
  • this test is done to determine if the increase in cortisol is due to pituitary tumor or ectopic small cell lung cancer.
  • if pituitary tumor the dexamethosone overrides the tumor and shuts down ACTH secretion leading to low levels in the blood and lower levels of cortisol.
  • if ectopic small cell lung cancer; the dexamethasone has no effect and there will be large levels of ACTH and cortisol in the blood.
25
Q

Adrenal Insufficiency

-what are the two forms?

A
  • Primary adrenal insufficiency: Addisons Disease, results from destruction or dysfunction of the adrenal cortex. (autoimmune) Both glucocorticoid and mineralcorticoid secretion are diminished.

Secondary: results from inadequate stimulation of adrenal cortex by ACTH. (pituitary doesnt secrete ACTH, usually occurs after discontinuation of exogenous steroids)oo

26
Q

Sx of Adrenal insufficiency

A
  • hypotension
  • weight loss
  • increased fatigue
  • vomiting
  • diarrhea
  • anorexia
  • muscel and joint pain
  • abd pain
  • postural dizziness
27
Q

Sx of Addisons Disease

A

Hyperpigmentation: decreased levels of cortisol means less inhibition of HPA axis. Increased POMC synthesis which is a precursor to ACTH. POMC contains MSH, therefore increased POMC= increased MSH»>hyperpigmentation\

-Salt cravings: low secretion of aldosterone which leads to hyponatremia and salt craving.

28
Q

Lab test results leading you to adrenal insufficiency dx

A

-low levels of AM cortisol

  • Plasma ACTH levels: give ACTH and recheck cortisol..
  • -if increased:secondary adrenal insufficiency (pituitary)
  • -if decreased; primary adrenal insufficiency
29
Q

Which type of addisons disease would you most likely have if you have elevated/decreased levels of plasma ACTH?

A

Elevated: Primary Adrenal Insufficiency

Decreased: secondary adrenal insufficiency

30
Q

Tx: Addisons Disease

Addisonian Crisis

A
  • lifelong replacement of glucocorticoids and mineralocoids (tx should mimic normal physiology)
  • DOC: hydrocortisone

Tx Crisis:
-prompt recognition and IV hydrocortisone

31
Q

What is the most important education you can provide your patients on long term steroid use?

A

-DDONT STOP ABRUPTLY!!!

32
Q

What are some common signs you will see in patient with adrenal insufficiency?

A
  • decreased aldosterone: hypnatremia, hyperkalemia, salt craving, hypotension
  • decreased cortisol: hyperpigmentation, weight loss
33
Q

Name a few prescription Glucocorticoids & Mineralocorticoids

A
  • Hydrocortisone*
  • Prednisone
  • Methylprenisolone
  • Dexamethasone*

Mineralocorticoids:
-fludrocortisone

34
Q

Adverse Effects of Prescription COrticosteroids

A
  • osteoporosis
  • cushingoid appearance
  • hyperglycemia
  • suppressed immune system
  • CNS and mental status effects
  • Elevation of BP
  • Stimulate gastric acid and pepsin production.