Thyroid/Parathyroid 1 Flashcards
Thyroglobulin
–Protein that synthesizes and stores T3 and T4
another name for T3
–T3 (3,5,3’-triiodothyronine)
–Fatigue, weakness
–Cold intolerance
–Weight gain
–Cognitive dysfunction
–Constipation
–Slow movement/speech
–Delayed relaxation DTRs
–Bradycardia
s/sx of what dz?
Hypothyroidism (generalized metabolic slowing)
–Dry, coarse skin
–Hoarseness
–Edema
–Puffy facies
–Loss of eyebrows
–Periorbital edema
–Tongue enlargement
S/sx of what dz?
hypothyroidism (Accumulation of extracellular matrix substances)
what labs would you see for primary hypothyroidism?
high TSH: (4-5)
low T4
what would you see on labs of subclinical hypothyroidism?
normal T4
High TSH
what other labs should you look at when dx hypothyroidism?
BMP (Na, Cr)
Lipids
Drug levels
What conditions will you see elevated Anti-TPO antibodies?
Hashimoto’s thyroiditis
Grave’s disease
what conditions will you see elevated anti-thyroglobulin antibodies in? (anti-TGB)
Hasimoto’s thyroiditis
Grave’s dz
what antibody will be elevated in 65% of pts w/graves dz?
Thyroid Stimulating Immunoglobulin (aka TSH Receptor Antibody)
MCC of hypothyroidism
autoimmune thyroiditis (hashimotos)
OTHER causes of hypothyroidism
- Iatrogenic
- Iodine deficiency or excess
- Medications
- Transient
- Infiltrative (rare)
- Congenital
hypothyroidism tx
Synthetic thyroxine (T4) replacement to achieve and maintain euthyroid state (Levothyroid)
PK of T4 (Levothyroxine)
high abs, long 1//2 life
what is the avg dose of T4 (levothyroxine)?
1.6 mcg/kg/day
T4 dosage for elderly
start on low dose
T4 dose for pts with hx of coronary hrt dz
no higher than 25mcg
goals of tx for hypothyroidism
–Symptom relief
–Normalization of TSH secretion
–If applicable, decrease in goiter size
What are other tx options for hypothyroidism?
T3 (Cytomel)/T4 combo therapy
Dessicated thyroid extract (Armour Thyroid, Nature Throid)
About 1/3 to ½ progress to overt hypothyroidism
subclinical hypothyroidism
possible conditions associated with subclinical hypothyroidism?
–CV disease
–NAFLD
–Neuropsychiatric
–Reproductive
when should you initiate tx for subclinical hypothyroidism?
–TSH > 10
MCC of hyperthyroidism
grave’s dz
Other etiologies of hyperthyroidism
Hashimoto’s thyroiditis
Autonomous thyroid tissue: Toxic adenoma, Toxic multinodular goiter
TSH-mediated hyperthyroidism: TSH-producing pituitary adenoma, Non-neoplastic TSH-mediated hyperthyroidism
Human chorionic gonadotropin-mediated hyperthyroidism
which condition has normal or high RAI uptake?
hyperthyroidism
•Skin changes
•Stare and lid lag
•Graves’ ophthalmopathy
•Cardiovascular
•Low total and HDL cholesterol
•Impaired glucose tolerance
Clinical px of what?
Hyperthyroidism
•Dyspnea and DOE
•Weight loss
•Normochromic, normocytic anemia
- Genitourinary
- Bone changes
- Neuropsychiatric changes
Clinical px of what?
hyperthyroidism
what labs will you see on hyperthyroidism?
low TSH
high T3/T4
+ TSH receptot a-bodies
What diagnostic test should you order for Hyperthyroidism?
24 hr radioiodine uptake & scan
what does a high uptake vx. low uptake on a 24-hr radioiodine uptake scan mean?
–High uptake = increased hormone synthesis
–Low uptake = inflammation/destruction of thyroid gland or extrathyroidal source of thyroid hormone
CI for 24-hr radioiodine uptake and scan
preggos
breastfeeding
hyperthyroidism tx
–Beta-blockers
–Thionamides: Methimazole, Propylthiouracil (PTU)
–Radioiodine ablation
–Surgery
MCC of thyroiditis
subacute granulomatous thyroiditis (de Quervain’s)
–Can present with acute symptoms or silently
–Common in young or middle-aged females
–Associated with viral illnesses
–Acutely painful glandular enlargement with dysphagia
–Can last from weeks to months
clinical px of what?
thyroiditis (de Quervain’s)
dx of thyroiditis
clinical dx w/labs
thyroiditis may be followed by what?
hypothyroidism
thyroiditis tx
anti-inflammatories (ASA, NSAIDS, prednisone)
sx mgmt
Rare, endocrine emergency
High mortality
Usually results from an acute event
Which dz?
thyroid storm
thyroid storm RF
–Surgery
–Trauma
–Infection
–Iodine administration
–Childbirth
–Withdrawal of antithyroid meds
–MI, CVA, PE
Main Clinical signs of thyroid storm
Cardiac: tachy, CHF, hypotension
Fever
aditation, anxiety
stupor, coma
N/V/D
Hepatic failure
warm, moist skin
lig lag
Thyroid storm dx
Clinical presentation of severe, life-threatening symptoms
PLUS
Low TSH, high free T4/T3 (same as hyperthyroidism)
thyroid storm tx
ICU
Beta-blocker – sx control
Thionamide – block new hormone synthesis
Iodine solution – blocks release of thyroid hormone from gland
Glucocorticoids – reduces T4 to T3 conversion, promotes vasomotor stability, treat associated related adrenal insufficiency
Bile acid sequestrants – decrease enterohepatic recycling of thyroid hormones
definitive tx for thyroid storm
radioablation of gland
how does beta blocker tx thyroid storm?
sx control
how does thionamide tx thyroid storm?
blocks new hormone synthesis
how does iodine solution tx thyroid storm?
blocks release of thyroid hormone from gland
how do glucocorticoids tx thyroid storm?
reduces T4 to T3 conversion, promotes vasomotor stability, treat associated related adrenal insufficiency
how do bile acid sequestrants tx thyroid storm?
decrease enterohepatic recycling of thyroid hormones
