Thyroid Disorders Flashcards
Hypothyroidism main Etiology
almost always from a single cause: failure of the thyroid
gland from burnt-out Hashimoto thyroiditis.
Hypothyroidism less common Etiology
Dietary deficiency of iodine
AmIODArone
Hypothyroidism cx fx
almost all bodily processes being slowed
down—except menstrual flow, which is increased.
Hypothyroidism management if TSH is very high (more than double the upper limit of normal) with
normal T4,
replace hormone. thyroxine (Synthroid)
Hypothyroidism management if TSH is less than double the normal
… wait old note that sounded weird..
here is a new one
Remaking the question:
You have low T4 and T3, High TSH. How would you confirm primary hypothyroidism?
get antithyroid peroxidase/antithyroglobulin antibodies. If antibodies are positive, replace thyroid hormone.
they are typical for Hashimoto’s thyroiditis= the classic one (but may also be present in Graves’ disease).
Think of Hashimoto as jaPanese Tyrona de Globos
Hypothyroidism intestinal transit
Constipation
Hypothyroidism refelxes
Decreased reflexes
Hypothyroidism cold or hot
Cold intolerance
Hyperthyroidism intestinal transit
Diarrhea (hyperdefecation)
Euthyroid Sick Syndrome patho
nonthyroidal systemic illness + low serum levels of thyroid hormones
Euthyroid Sick Syndrome Dx
t3 low
reverseT3 high
+- t4 low (t4 is converted into rT3)
TSH NO HIGH!
Euthyroid Sick Syndrome tx
treat the underlying cause. NO hormone replacement
Euthyroid is written with E like the number 3= the only affected hormone is T3. This is all because a non-thyroidal disease
Don’t order thyroid function tests in
patients with ____________. The results will not be
accurate.
nonthyroid critical
illness
What Is the Most Likely Diagnosis?” Eye (proptosis) (20%–40%) and skin (5%)
findings
Graves disease
What Is the Most Likely Diagnosis? Tender thyroid
Subacute thyroiditis
Painless “silent” thyroiditis cxfx
Nontender, normal exam results
What Is the Most Likely Diagnosis? Involuted gland is not palpable
I guess + High t3t4
Exogenous thyroid hormone
use
Etiology/“What Is the Most Likely Diagnosis?” high tsh level
Pituitary adenoma
Hyperthyroidism dx
All forms of hyperthyroidism have an elevated T4 (thyroxine) level.
Graves disease dx
only kind of hpth that has TSH receptor antibodies.
Indication: if Graves disease is suspected but classic clinical features are absent
Thyroglobulin Significance
Detects recurrence of thyroid cancer
Thyroid-stimulating immunoglobulin TSI) Significance
Confirms Graves disease
Not positive in toxic multinodular goiter
Thyroperoxidase antibody (TPO) Significance
Confirms presence of Hashimoto
thyroiditis
Graves disease
labs: TSH, RAIU, Confirmatory
TSH low, RAIU ↑, Confirmatory: positive antibody test (TSI)
[TSH receptor antibody =TRAb]
Subacute thyroiditis
labs: TSH, RAIU, Confirmatory
TSH low, RAIU ↓, Confirmatory: tenderness
Painless “silent” thyroiditis
labs: TSH, RAIU, Confirmatory
TSH low, RAIU ↓, Confirmatory:none
Exogenous thyroid
hormone use
labs: TSH, RAIU, Confirmatory
TSH low, RAIU ↓, Confirmatory: History and involuted, nonpalpable gland
Pituitary adenoma
labs: TSH, RAIU, Confirmatory
TSH ↑, RAIU not done, Confirmatory MRI oh head
Radioactive iodine uptake measurement (RAIU test):
a test that quantifies the percentage of the administered amount of radioactive iodine taken up by the thyroid gland
Toxic nodule:
labs: TSH, RAIU, Confirmatory
↓ TSH ↑ RAIU Focal uptake of radioactive iodine Graves is diffuse
Graves disease Tx
Radioactive iodine. thioamides: PTU or methimazol
Subacute thyroiditis tx
Aspirin
Painless “silent” thyroiditis tx
None
Exogenous thyroid hormone use tx
Stop use
Pituitary adenoma tx
Surgery
Treatment of Acute Hyperthyroidism and “ Thyroid Storm
cold IV fluids
1 Propranolol: blocks target organ effect, inhibits peripheral conversion of
T4→T3
2 Thiourea drugs (methimazole or propylthiouracil): blocks hormone
production
3 Iodinated contrast material (iopanoic acid and ipodate): blocks the peripheral
conversion of T4 to the more active T3; also blocks the release of existing
hormone
4 Steroids (hydrocortisone)
5 Radioactive iodine: ablates the gland for a permanent cure for all …qx resection for Graves is rarely done alternative!
Graves Ophthalmopathy tx
Steroids are the best initial therapy. Radiation is used in those not responding to
steroids. Severe cases may need decompressive surgery.
Graves disease important cxfx
esophtalmos
pretibial myxedema
hashimoto’s tyroditis patho
after inflamated, it dies
multiondular goiter
toxic adenoma
tons of t4.
factitious disorder hyperthyroidism
someone who intentoinaly takes t4
struma ovarii
ovarian lesion produciong t4
struma ovarii and factitious disorder hyperthyroidism
both have cold tyroid
when to treat a subclinical hypothyroidisim
only if tsh>=10 OR
if there arre symptoms
myxedema coma
coma+hypothermica+hypotensjon dur to too low t4.
myxedema coma tx
IVF
blankets
give t4. not working? t3
amboss:IV combination of levothyroxine and liothyronine plus IV hydrocortisone
o sea t4+t3
