Pit gland disorders Flashcards
What does the anterior pit gland secrete?
thyroid stim hor, ACTH, 4 more
What does the posterior pit gland secrete
Antidiuretic (vasopressin) hormone, oxytocin
How are cortisol and aldosterone secreted?
ACTH stims release of cortisol and aldosterone from the adrenal cortex
What lab is used to dx adrenocorticoid dysfunction
ACTH levels
What does the adrenal medulla do?
Secrete EPI and NOR when SNS stim, triggering fight or flight response
What does the cortex release in response to ACTH?
Steroids;
cortisol, aldosterone (mineralocorticoids), sex steroids (androgens)
“sugar, salt, and sex”
Cushing’s
Hypercortisolism - ACTH stims the cortex which stims the hypo to stim the cortex release excess cortisol (neg feedback)
Primary hyperfxn
dysfxn adrenal cortex releases excess cortisol (actual gland dysfxn); Cushing SYNDROME
Secondary hyperfxn
dysfxn with anterior pituitary gland makes lots ACTH which makes excess cortisol; Cushing DISEASE
What can long dose EXOGENOUS steroids cause?
Cushing syndrome (prednisone, dexamethasone)
- most common cause
When might patients with Cushing need extra ACTH?
before surgery bc they can’t respond to natural triggers
Are endogenous steroids stored on hand?
NO - must be created
Cortisol functions
- raises blood sugar (opposes) insulin
- protects against stress
- b/d pro and fat - inc chol and BP
- suppresses immune and inflam responses
Does ACTH rise during a “normal” stress response in someone with Cushing’s?
NO - can lead to pit atrophy
Cushing’s CM
- glucose intolerance, hyperG
- HTN, capillary friability (ecchymoses)
- muscle waste, weakness, thin skin, osteoporosis, bone pain from inc pro b/d
- redistribute fat to ab, shoulders, face from fat b/d
- dec wound heal, inc risk infx
- mood swings, insomnia from CNS excite
- hirsutism
- gynecomastia
- moon face
- buffalo hump
- wide abdomen and thin extremities
Cushing tx
Depend on cause; taper drug PRN, surgery or radiation for tumor, drugs
Aminoglutethimide MOA
blocks synth of all adrenal steroids
Aminoglutethimide SE and NC
- Drowsy, nausea, anorexia, rash
- not use longer than 3M
- does not affect underlying disease process
ketoconazole MOA
Antifungal drug that inhibits glucocorticoid synthesis
When is ketoconazole given?
Adjunct therapy to surg or radiation for Cushing
ketoconazole SE and NC
- severe liver damage
- don’t take with alc or other drugs that harm liver
- NO PREG (fetal thyroid damage)
Addison disease
Disease of adrenal cortex that causes hyposec of all adrenocortical hor
Addison cause
idiopathic, autoimmune, or other
Addison disease patho
ADrenal gland destroyed so cortex not functioning, cortisol not produced, lack of negative feedback so ant pit increases ACTH and melanocyte stim hor to inc cortisol but doesn’t work so just have high ACTH
When is Addison often dx
Far into diesase process
Addison early CM
Anorexia, wt loss, weakness, malaise, apathy, electrolyte imbalances, skin hyperpigmentation
Addison later CM
Hypoaldosteronism (hypotension, dec CO, vasular tone, and blood vol)
- get salt craving and dec NA, inc K, dehydration
Hypocortisolism
- hypogly, weak and fatigue, high ACTH, hyperpig
Addison pharm
- needs to be LIFELONG
- all need glucocorticoid (pred, dexa)
- some need mineralcorticoid (fludro)
- often get Hydrocortisone bc has gluc and mineral properties
- often PO
Addisons pharm
- dosing should mimic natural release (all bed or mix morn and bed)
- TAPER bc can cause Addisonian crisis
- dose need to inc during stress or can be fatal (infx, surg, trauma)
- always need emergency supply (oral and IJ)
- wear medic alert bracelet
3x3 rule
For Addisons, take 3x normal dose for 3 days during high stress
Severe Cushing Syndrome
- emergency
- rapid mass of random inc cortisol at any time or 24h free floating cortisol 4x UL
- assoc w/ onset sepsis, opportunistic infx, HTN, HF
- severe hypokalemia
Addisonian crisis aka acute adrenal insufficiency
- sudden insuff or serum corticosteroids
- sudden inc stress with chronic disease or sudden inc corticosteroid drug therapy
- body crash - medical emergency
- lack stress hor
Pheochromocytoma
Rare tumor of the medulla that releases excess catecholamine in response to SNS stim
- often benign “oma”
Pheochromocytoma risk factors
often young, middle aged adult
Pheochromocytoma CM
HTN, HA, diaphoresis, tachy
- episodes with stress and exercise
Big risk of Pheochromocytoma
STROKE
Tx for Pheochromocytoma
- relaxation, low stress
- surgery is best
- alpha blockers until surg or for inoperable tumors or preop to dec HTN
Phenoxybenzamine HCl class, indications, and MOA
- alpha 1 adrenergic blocker
- pheochromocytoma
- Long-lasting, irreversible blockage of alpha-adrenergic receptors—vasodilation
Phenoxybenzamine HCl SE and NC
- Dec BP, orthostatic hypotension, reflex tachycardia, nasal congestion, sexual SE in men
- given until surg or for inoperable tumor or preop to dec HTN
