Endocrinology Flashcards
History: Two weeks generalized weakness, not eating
PE: Underweight, hyper-pigmented palmar creases, serum sodium 130, serum potassium 5.8
Dx?
Dx: Primary adrenal insufficiency (Addison’s)
ADDISON’s Mnemonic:
A - Autoimmune dz (primary cortical adrenal insufficiency)
D- Dark skin - hyperpigmentation
D - Drained - generalized weakness, tired, lethargic, emotional changes
I - Iatrogenic (possible cause)
S - starvation - anorexia (no appetite), weight loss,
O - hypOtenstion, hypoglycemia, hyper-K+
N - N/V/D, ABD pain, fever muscle/joint pain, severe debhdration- si adrenal crisis
Dx: Low cortisol, high ACTH - further testing w/ cosyntropin (synthetic acth) - normal person = cortisol level doubles - Addison = no inc
Tx: GC (Hydrocortisone)
Note: Hypo/hyperthryoidism does NOT cause electrolyte abnormalities - think issue with adrenal gland
Also hypothyroidism causes fatigue/lethargy with generalized weakness but causes weight GAIN, not loss & also causes edema, cold intolerance
Cushings = gushing cortisol
Conn syndrome = opposite = excess aldosterone
What is the best way to screen for diabetes mellitus?
Fasting plasma glucose = BEST WAY
>126 on TWO occasions
OR
Sx of DM + random plasma glucose >200
OR
Glucose >200 TWO hours after 75 g load of glucose during oral tolerance test
OR
HgA1c >6.5%
RF for DM
BMI >25 Age >45 Family Hx 1st deg rel HTN HLD Sedentary lifestyle
REVIEW PATIENT RISK FACTORS AND DO SCREENING ON ALL PATIENTS who have >1 RF ?
How often should patients be screened for DM?
Every 3 years
RAIU - increased diffuse uptake = ?
Hyperthryoid 2/2:
Graves disease
TSH-secreting pituitary adenoma
RAIU - decreased uptake = ?
Hypothyroid 2/2:
Thyroiditis (hashimoto’s, postpartum, dequervain)
RAIU - hot nodule
Toxic adenoma
RAIU - cold nodule
Rule out malignancy
RAIU - multiple nodules
Toxic multinodule goiter
Cretinism - = what? CP? Tx?
Cretinism = congenital hypothyroidism 2/2 maternal hypothyroidism or infant hypopituitarism
CP: Macroglossia, hoarse cry, coarse facial features, weight gain, umbilical hernia
**Mental development abnormalities if not corrected
Tx: Levothyroxine
Causes of hypothyroidism
Iodine deficiency Hashimoto's thyroiditis Postpartum thyroiditis Pituitary hypothyroidism Hypothalamic hypothyroidism Cretinism Reidel's thyroiditis
Sx of hypothyroidism
Dec BMR Cold intolerance Dry, tough skin Weight GAIN (despite being hungry) Non-pitting edema (myxedema) Loss of outer 1/3 eyebrow CNS hypoactivity (sluggish, fatigued, depression) Constipation Bradycardia, dec CO Mehorrhagia Hypoglycemia
**Think of all the different body systems - shuts down all of them!
Sx of hyperthyroidism
Increased BMR Heat intolerance Weight loss (even w/ inc appetite) Skin is warm, moist, soft, fine hair CNS hyperactivity (anxious, fine tremors, nervousness, fatigue) Diarrhea, hyperdefecation Tachycardia, palp, HOHF Scanty periods, gynecomastia Hyperglycemia
**Think of all the different body systems - puts all of them into overdrive!
Euthyroid sick syndrome
Abnormal findings on TFTs that occur in the setting of non-thyroidal illness, without pre-existing HPT dysfunction - common in MI, DKA, CRF, cirrhosis surgery, malignancies, sepsis,
Dx: Dec Free T4/3, Dec TSH
Note: Often resembles 2ry hypothyroidism lab-wise but it’s rare/weird to have 2ry thyroid disease that’s HYPO - so think of this if person is ill and has labs consistent w/ 2ry hypOOO-thyroidism
*T3 can also be low w/ increased reverse T3
Thyrotoxicosis (thyroid storm)
Happens after precipitating event like SURGERY, TRAUMA, INFECTION –> rare (1-2% of pt w/ hyperyhyroidism) but DEADLY (75% mortality rate)
CP: Hypermetabolic state - palp, tachy, afib, high fever, n/v, psychosis, tremors
Dx: Dec TSH (undetectable), and HIGH HIGH T4/T3
Tx: Anti-thyroid meds IV propylthiouracil (PTU) - inhibits thyroid hormone synthesis and prevents conversion of T4-> T3 peripherally or methimazole
Sx therapy: Tx palps w/ beta blockers
Supportive therapy: IV glucocorticoids, cardiac monitoring, IV fluids, cooling blankets, antipyretics (APAP)
Myxedema coma
Hypometabolic state = coma - so remember mxyedema coma = thyroid is CRITICALLY LOW
Extreme form of hypothyroidism a/w HIGH mortality rate
MC seen in elderly women with longstanding hypothyroidism in WINTER
Patho: 2/2 precipitating factor - infection, CVA< CHF - WITH long-standing undiagnosed hypothyroidism, discontinuation or noncompliance with levothyroxine therapy, failure to start levothyroxine after RAI ablation of thyroid patients w/ graves
CP: SEVERE sx of hypothyroidism- brady, obtunded, hypothermic, hypoventilation, hypoglycemia, hypotension, hyponatremia
Dx: HIGH serum TSH, LOW Free T4/3 (may be undetectable)
Tx: IV LEVOTHYROXINE, ICU admission, abx if infection, passive warming (blankets, warm room…RAPID WARMING C/I), IVF, IV corticosteroids if adrenal insufficiency is suspected
Grave’s disease - MC in? CP, Dx, tx?
Autoimmune disorder - body makes ab that activate the TSH receptor in the thyroid gland = inc thyroid hormone synthesis & thyroid gland growth
Worse w/ stress (pregnancy, illness)
CP:
Si/sx clinical hyperthyroidism
Diffuse enlarged thyroid
Thyroid BRUITS
Exophthalmos, proptosis, lid lag 2/2 hyalauronic acid deposition
Pretibial myxedema - (name = misnomer) = nonpitting edematous pink to brown plaques on shins
Dx: + TSH antibody, hyperthyroid TFTs (low TSH, high Free T4/3)
Tx: RAI ablation - destroys thyroid gland - needs replacement after - can also use PTU, Bb for tachy sx
Describe typical pt w/ Graves
Nancy Grave = 20-40 YO woman who smokes POT (pretibial myxdedema, ophthalmopathy, thyroid bruits/enlargement) to chill her out b/c she’s a nervous nelly w/ palp, hot all the time, skinny, losing weight, poops all over, skin shiny, hair fine
Nancy is a total hot mess
Toxic multinodular goiter and toxic adenoma
TMG = multiple autonomously functioning thyroid nodules
TA = one autonomously functioning nodule
CP = clinical hyperthyroidism (no skin or eye changes - exopthalmos = unique to graves)
PE = palpable nodule(s)
Dx = Dec TSH, Inc Free T4/3
RAIU TMG = patchy areas of both inc and dec uptake
RAIU TA = HOT nodule (inc local uptake in one area)
Tx TMG & TA = RAI ablation (MC) or meds (PTU - inhibits thyroid hormone synthesis, preferred in pregnancy )
TSH-secreting pituitary adenoma
MCC SECONDARY hyperthyroidism = autonomous TSH secretion by pituitary adenoma
CP/PE = clinical hyperthyroidism w/ diffuse enlarged thyroid, BITEMPORAL HEMIANOPSIA (bc tumor presses on optic chiasm), mental disturbances
Dx = HIGH TSH, HIGH FT4/3, RAIU = diffuse uptake
Suspect adenoma…get brain MRI
Tx = transsphenoidal surgery to remove pituitary adenoma
Hashimoto’s thyroiditis
AKA chronic lymphocytic
MCC hypothyroidism in the US 6x MC in women
Patho: AI antibodies against thyroid
CP: Clinical hypothyroidism, painless enlarged thyroid, may present euthyroid
Dx:
+ Thyroid Ab present (thyroglobulin ab, antimicrosomial ab, thyroid peroxidase ab)
TFTs - hypothyroid
RAIU decreased (usually not needed for dx)
Tx:
Levothyroxine
Silent (Lymphocytic) thyroiditis
Autoimmune - anti-thyroid ab in 50% - occurs after exposure to certain drugs, such as IFN-alpha, IL-2, lithium etc
CP: Ranges from thyrotoxicosis (first) to hypothyroid (depends on when they present)
Dx: + Thyroid Ab present (thyroglobulin ab, antimicrosomial ab, thyroid peroxidase ab)
Tx: return to euthyroid state w/in 12-18 mo without tx –> NO ANTITHYROID meds - 20% will end up with permanent hypothyroidism (chronic lymphocytic thyroiditis AKA Hashimoto’s)
Postpartum thyroiditis
Literally the exact same as silent lymphocytic thyroiditis except the thyroiditis occurs postpartum - thought to be AI (+Ab in > 80%)
CP: Ranges from thyrotoxicosis (first) to hypothyroid (depends on when they present)
Dx: + Thyroid Ab present (thyroglobulin ab, antimicrosomial ab, thyroid peroxidase ab)
Tx: return to euthyroid state w/in 12-18 mo without tx –> NO ANTITHYROID meds
Recurrence rate high –> can turn into chronic lymphocytic thyroiditis AKA Hashimoto’s
Which two kinds of thyroiditis can turn into chronic lymphocytic thyroiditis if they progress instead of returning to euthyroid?
Silent lymphocytic thyroiditis
Postpartum thyroiditis
Literally exact same patho –> 20% of above cases will become recurrent or permanent = when you are considered to have chronic lymphocytic thyroiditis AKA hashimoto’s aka autoimmune thyroiditis
Two above can present as hyperthyroid, euthyroid or hypothyroid!!
If present hyperthyroid, are differentiated fro graves via absence of exopthalmos/ocular involvement
All three (silent, pospartum, chronic) = painless, enlarged thyroid vs dequervain’s thyroiditis = PAINFUL (see next card). All 4 kinds of thyroiditis have decreased RAIU on scan