Endocrinology Flashcards
What will a serum study show early in in DM1?
Anti-islet and anti-glutamic acid decarboxylase (anti-GAD) antibodies
This is NOT the case in DM2
What are the 5 criteria for metabolic syndrome? How many do you need to meet the Dx?
Waist: >40 in men, >35 in women
TAG: >150
HDL: 130/85 or currently on antiHTNs
Fasting Glucose: >100 mg/dl
Side Effects of DM drugs: Sulfas (glipizide) Metformin Thiazolidinedoines (Glitazone's) a-glucosidase inhibitors DPP4 blockers (Sitaglyptin) Incretins (GLP-1 agonists)
Sulfas (glipizide) = weight gain
Metformin: weight loss, GI, lactic acidosis
Thiazolidinedoines (Glitazone’s): weight gain, edema, hepatic tox, bone loss
a-glucosidase inhibitors: flatus
DPP4 blockers (Sitaglyptin): none
Incretins (GLP-1 agonists): nausea, pancreatitis
MOA of DM drugs: Sulfas (glipizide) Metformin Thiazolidinedoines (Glitazone's) a-glucosidase inhibitors DPP4 blockers (Sitaglyptin) Incretins (GLP-1 agonists)
Sulfas (glipizide): increase insulin secretion
Metformin: blocks hepatic gluconeogenesis and increases sensitivity to insulin
Thiazolidinedoines (Glitazone’s): increases insulin sensitivity
a-glucosidase inhibitors: decrease absorption of carbs
DPP4 blockers (Sitaglyptin): blocks GLP-1 degredation
Incretins (GLP-1 agonists): increases insulin secretion and decreases glucagon secretion
When do you use an RAI uptake test?
When you are diagnosing hyperthyroidism
It doesn’t do much for dx malignancy
Why is total T4 not a good screening test?
Most T4 is bound to TGB, and this protein can fluxuate with bodily states (pregnancy etc.)
it is better to measure free T4
What states increases TBG?
pregnancy, estrogen therapy, infection, nephritic syndrome
Higher TBG will cause less T4 to be free and active
What causes Graves dz? What will the RAI look like?
autoAbs that stimulate the thyroid receptors and secrete free T4/T3.
RAI will be increased uptake diffusely
What causes a toxic adenoma (Toxic Multinodular Goiter)? What will the RAI look like?
It is an autonomous hyperactive nodule.
RAI uptake will be increased only in the nodule w/ decreased uptake elsewhere.
What causes thyroiditis? What will the RAI look like?
Viral state, postpartum, can cause inflammation of the gland which will release PREFORMED T4/T3.
RAI uptake will be decreased
A HYPOthyroid STATE MAY FOLLOW!
What effect does DA, Somatostatin, and Glucocorticoids have on the thyroid?
They all inhibit TSH release @ the pituitary
What is the tx for a thyroid storm?
Propranalol (get that BP down), PTU, and CTSDs
Do a high dose K+ iodide if it is bad enough.
What is the cause of Hashimoto’s Thyroiditis?
autoAbs that block thyroglobulin, and antimicrosomal (TPO)
What is the tx for myxedema coma?
URGENT TX IN ICU (mortality of 30-60%)
Tx = CTSDs (hydorcortisone) and levothyroxine
What medication can cause thyroiditis?
Amiodarone
What is the only form of thyroiditis that presents with painful thyroid?
subacute thyroiditis
Papillary Thyroid CA
Most common form of thyroid CA
Found in follicular cells
branching (papillary)
orphan annie eyes/psamomma bodies
positive prognosis
Follicular Thyroid CA
Also in the follicular cells
Not as common as papillary CA
INVASION OF CAPSULE AND BLOOD VESSELS WILL MEAN ITS FOLLICULAR CA AND NOT ADENOMA
Medullary Thyroid CA
Found in the C-cells (calcitonin +)
Invades vascularly
associated with MEN 2A/B
Anaplastic Thyroid CA
Metz quickly and big time
Bad prognosis
Rarest
What is the criteria for osteoporosis?
BMD
Pagets disease
Dz of increased bone turn over.excessive resorption
Caused by latent viral infections
Mosaic lamellar bone (looks like weird thickening on XR)
Associated w/ 1* hyperPTH
labs: increased alk phos w/ normal Ca and Phos
Can cause high output HF
When does 3* hyper PTH occur?
In dialysis pts (chronic RF w/ inability to make Vit D and thus no Ca) leading to chronic hyperPTH to the point of hyperparathyroid hyperplasia
What do the labs of 1, 2, and 3* hyperPTH look like?
1* (or ectopic PTH sec): hi Ca, low P, hi Ca in urine, hi PTH
2: nm/low Ca, hi P, hi PTH
3 hi Ca, P, and PTH
Define ACTH dependent increase cortisol
If cortisol lvls correlate w/ ACTH levels, then the cause is cushings Dz (pit adenoma) or ectopic tumor (lung)
If cortisol and ACTH act independently, the cause is adrenal or exogenous steroid use
Dexamethasone Suppression Test
Decreased in cusings
Increased (negative) in ectopic tumor/steroid use
What symptoms will acromegaly have (other than the obvious?) Tx?
carpel tunnel, DM, diastolic disfunction, b/l hemianopsia
Tx: Octreotide (somatostatin) will decrease GH secretion. Pegvisomant (GH receptor antagonist)
Medical tx for increased prolactin levels?
Dopamine (cabergoline, bromocriptine)
Sheehans Syndrome?
post partum post pit ischemia causing decreased ADH (which causes central D.I.)
What medication can cause Nephrogenic D.I.?
Lithium
DDAVP will treat central DI but not nephrogenic. How do you treat nephrogenic?
b/c nephrogenic DI has a decreased sensitivity to ADH.
Tx instead w/ hydration, decreased salt intake, thiazides
What lung dz causes SIADH? What does the urine osm, and urine Na look like?
small cell lung CA, but also sarcoid, COPD, or PNX
Urine Osm will be hi (>50-100)
Urine Na will be >20 (indicating that the pt is NOT dehydrated.
What is the Tx for SIADH?
Demeclocycline (ADH antagonist)
What is the most common cause of 1* Adrenal Insuffiency worldwide? US?
world = TB, then Neisseria Men
US: autoimmune (addisons dz)
MEN 1
MEN 2A
MEN 2B
MEN 1 = Pituitary, Parathyroid, Pancreas (ZE syndrome w/ islet cell tumor or insulinoma/VIPoma)
MEN2A: Medullary Thyroid CA, Pheo, Pituitary
MEN2B: Medullary Thyroid CA, Mucosal tumors, Pheo, MARFANS
What enzyme will be high in Congenital Adrenal Hyperplasia?
17-hydroxyprogestreone (cant form 21-hydroxy)
Electrolyte issues = low Na, high K, metabolic acidosis.
