Endocrine #1 Flashcards
A somtatotroph adenoma, an anterior pituitary tumor, secretes ________ that leads to acromegaly in adults or gigantism in children.
Growth Hormone (GH)
Growth Hormone (GH) increases ________.
Increased GH also stimulates hepatic production of what other hormone?
GH increases glucose
Increased GH also increases insulin-like growth factor (IGF)
Symptoms of Acromegaly/Gigantism
-Diabetes Mellitus or glucose intolerance
-Enlargement of soft tissues, cartilage and bone (macrognathia, increased ring/shoe/hat size)
-Obstructive sleep apnea, carpal tunnel syndrome, increased space between teeth, deepened voice
-Headache, Bitemporal Hemianopsia, thick/moist/doughy skin
-Hypertension, kidney stones, colonic polyps
Screening test for Acromegaly/Somatotroph Adenoma
Confirmatory Test
What imaging study should be done?
-Screening: insulin-like growth factor
-Confirmatory: oral glucose suppression test. Increased GH levels (normal is suppression of GH)
MRI of the pituitary
Management of somatotroph adenoma (acromegaly)
-Transsphenoidal surgery
-Octreotide or Lanreotide (somatostatin inhibits GH release)
-Cabergoline or Bromocriptine (dopamine inhibits GH release)
-Pegvisomant (GH receptor antagonist that inhibits insulin like growth factor release)
______ is the MC type of pituitary adenoma
Prolactinoma
Prolactin is responsible for _______, suppression of pregnancy during lactation, and suppression of gonadotropin-releasing hormone, leading to decreased FSH and LH.
_______ Inhibits prolactin release
-Lactation
-Dopamine
Symptoms from a prolactinoma are due to ______
Women:
Men:
-Hypogonadism
-Women: amenorrhea, infertility, galactorrhea, headache/vision changes from local compression
-Men: ED, decreased libido, infertility, headache/vision changes
-Bitemporal hemianopsia (optic chiasm compression)
What lab studies are expected with a prolactinoma?
What imaging study should be done?
-Increased prolactin, decreased FSH and LH
MRI of the pituitary
What is the treatment for a prolactinoma (think of what inhibits it)?
-Dopamine agonists (Bromocriptine, Cabergoline)
-Transsphenoidal surgery if refractory medical treatment, or women who wish to become pregnant
A corticotroph adenoma, is a pituitary adenoma that secretes _________, that leads to _________ (Cushing’s Syndrome).
Symptoms of this condition
-Secretes ACTH that leads to hypercortisolism (Cushing’s Syndrome)
-Proximal muscle weakness, weight gain, headache, ED, polyuria, osteoporosis, mental disturbances
A corticotroph adenoma is AKA ________.
Explain what differentiating tests are done (labs) and what is shown to determine the cause of the hypercortisolism.
-Also known as Cushing’s Disease
-Increased baseline ACTH + suppression of cortisol on high-dose Dexamethasone suppression
What imaging study should be done for a corticotroph adenoma?
What is the management?
MRI of the pituitary
Transsphenoidal resection is the treatment of choice
Symptoms of Growth Hormone Deficiency
-Children
-Adults
-Children: Short stature, growth delays, dwarfism, fasting hypoglycemia
-Adults: central obesity, hypertension, dysplipidemia, muscle wasting, decreased cardiac output, impaired concentration
How do you diagnose growth hormone deficiency?
What is the treatment?
-Arginine and sleep stimulation test: no change in GH if hypopituitarism
-Recombinant human GH
Multiple Endocrine Neoplasia I (MENI) has three main manifestations. Think of the 3 P’s.
What are the screening labs that should be done?
-Parathyroid (Hyperparathyroidism)
-Pancreatic Tumors: Gastrinomas (ZES)
-Prolactinomas
PTH + Calcium, Gastrin, Prolactin
Multiple Endocrine Neoplasia II (MENII) has four main manifestations. Name them.
What screening labs should be done?
-Medullary thyroid carcinoma, Marfanoid habitus, Pheochromocytoma, Neuromas (lips, tongue, eyelids, conjunctiva, nasal, and laryngeal mucosa)
-Calcitonin, epinephrine, PTH, calcium
For metabolic syndrome, you need 3 of the 5 criteria to diagnose. What are the 5 criteria?
-Low HDL: < 40 in men, < 50 in women
-High BP: > 135 SBP, > 85 DBP
-High fasting TG: > 150
-High fasting blood sugar: > 100
-High abdominal circumference: > 40 inches in men, > 35 inches in women
Or on treatment for any of them
Metabolic Syndrome, also known as Syndrome X, has one main component, which is __________.
Explain how this works and causes the other symptoms
-Insulin resistance is the key
-Free fatty acids are released, which causes an increase in TGs and insulin production.
-High levels of insulin lead to sodium reabsorption, leading to hypertension.
Management for metabolic syndrome (initial)
What medications can be used for weight loss?
-Weight reduction, exercise, activity, diet
-Phentermine
-Phentermine/Topiramate
-Lorcaserin: induces satiety
-Orlistat: inhibits fat absorption
SIADH is excess ADH from the __________ which leads to free water retention and hyponatremia due to kidney’s inability to dilute the urine to excrete excess water.
Pituitary gland or ectopic source
Etiologies of SIADH
-What is the MC
-Others
-CNS (MC): Subarachnoid hemorrhage, head trauma, stroke, hydrocephalus
-Small cell lung cancer, legionella PNA
-Anticonvulsants, Carbamazepine, Hydrochlorothiazide, Antidepressants, IV Cyclophosphamide, Ecstasy
Explain why hyponatremia occurs in SIADH
-Not enough water excreted, due to excess ADH
-This dilutes the blood, including sodium in the blood
-Leads to a low blood sodium level (hyponatremia)
Symptoms of SIADH
-Symptoms of hyponatremia and cerebral edema
–confusion, lethargy, disorientation, seizures, coma
