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Flashcards in Pituitary disorders Deck (21):

What is panhypopituitarism

Any condition that compresses or damages pituitary gland - tumors, trauma, radiation, infection, autoimmune, etc


What are the different presentations of panhypopituitarism

1.) Prolactin deficiency - men unaffected, women inhibits lactation after birth
2.) LH/FSH deficiency: Women become ammenorheic, men cannot make tesosterone or sperm and erectile dysfunction. Both decreased libido, decreased sex hair
3.) GH deficiency: Children have short stature, adults few symptoms


What are some specific diagnostic tests you can order for panhypopituitarism

1.) TSH levels - confirm with TRH injection
2.) ACTH/Cortisol levels - confirm with cosynthropin stimulation of adrenal (recent disease = normal rise, chronic disease atrophy = decreased rise), after CRH injection
3.) Decreased LH/FSH/testosterone - no test
4.) GH - no response to arginine or GHRH
5.) Prolactin - no response to TRH


What are other less useful tests for panhypopituitarism

1.) Metyrapone - inhibits 11-B hydroxylase, causing ACTH levels to rise because cortisol goes down
2.) Insulin stimulation - should cause GH to rise due to decreased glucose


What is the treatments for panhypopituitarism

Replace end hormones, not the stimulating hormones

Thyroxine, cortisone, testosterone/estrogen, GH


What is diabetes insipidus, the etiology of each, and the causes

Definition: Decrease in amount of ADH from pituitary (central DI) or its effect on kidney (nephrogenic DI)

1.) Central: Same causes as panhypopituitarism, idiopathic, or tumor producing
2.) Nephrogenic: Kidney diseases such as chronic pylonephritis, amyloidosis, myeloma, sickle cell disease. And hypercalcemia and hypokalemia. Caused by medications lithium and demeclocycline


What are the symptoms of diabetes insipidus

High volume urine and excessive thirst

If you don't match it with drinking water, will develop hypernatremia and subsequent neurological symptoms


How can you differentiate central and nephrogenic diabetes insipidus

Inject vasopressin - normal response = central, no response = nephrogenic


What is the treatment for central diabetes insipidus

Vasopressin long-term


What is the treatment for nephrogenic diabetes insipidus

Correct underlying cause, or hydrochlorothiazide, amiloride, and NSAIDS


What is acromegaly

Overproduction of GH leading to soft tissue growth through entire body


What is the number one, almost always cause of acromegaly

Pituitary adenoma, either alone or apart of MEN syndrome


How would a patient with acromegaly present on the USMLE

1.) Increased hat, ring, shoe size
2.) Carpal tunnel syndrome/OSA (compression from tissues)
3.) Body odor - sweat gland hypertrophy
4.) Coarsening facial features
5.) Deep voice/macroglossia
6.) Colonic polyps
7.) Arthralgias - joints growing out of alignment
8.) Hypertension
9.) Cardiac dysfunction


What is the diagnostic test for acromegaly

Best initial test - insulin like growth factor levels

Most accurate - Glucose suppression test (injecting glucose normally suppresses GH)

MRI - only after lab values are confirmed

Test prolactin too because cosecreted with GH


The treatment for acromegaly has both a surgical and medical one. What is the surgery

Transphenoidal resection of pituitary adenoma - 70% respond


The treatment for acromegaly has both a surgical and medical one. What is the medical treatments

1.) Cabergoline - dopamine inhibiting GH release
2.) Octreotide - somatostatin inhibiting GH release
3.) Pegvisomant - GH receptor antagonist - inhibits IGF from liver


What should you do if someone with acromegaly does not respond to surgery or medical treatment



What are the causes of hyperprolactinemia

Acromegaly (cosecreted) and hypothyroidism (high TRH)
Physiologic: Intense exercise and cutting pituitary stalk (dopamine eliminated), pregnancy, chest wall stimulation
Drugs: Think psych drugs - antipsychotics, SSRI's, tricyclics, metoclopramide, etc


What is the presentation for both men and women who have hyperprolactinemia

Women - galactorrhea, amenorrhea, and infertility
Men - Erectile dysfunction, decreased libido

All same symptoms as not having LH/FSH


What diagnostic tests should you do after you find that prolactin levels is high

Thyroid function tests, pregnancy test, kidney test since it can raise prolactin

Do MRI after these things are confirmed


What is the treatment for hyperprolactinemia

Dopamine agonists - cabergoline

Transphenoidal surgery if medications are not working