Thyroid Disease Flashcards
What is Estrogen therapy’s effect on the thyroid?
Increases the thyroid binding hormone
What drug can impact T4, T3, TSH, and TSAb lab test values?
BIOTIN
19 y/o female 3 month Hx of sweating, tremor, palpitations, and weight loss of 10 lbs. Recent heat intolerance, proximal muscle weakness.
Family Hx HYPO thyroidism
Exam: 156/60, P-92
Tremor, stare, Thryroid normal size, non-tender
What is your differential?
Graves Disease (Hyperthyroidism) Toxic multinodular goiter Toxic adenoma Subacute thyroiditis Iatrogenic
Which altered lab value could indicate and clinically help to definitively Dx Graves Dz?
What age group is it most common?
TSI and TSH-R –> Drives the thyroid to repeatedly causing the thyroid to create more T3 and T4
Widened pulse pressure
Age MC 20-50 y/o
What are some clinical features of a hyperthyroidism case?
Hyperactivity
Heat intolerance, sweating, weight loss
Tremor, palpitations
Oligomenorrhea
Tachycardia, arrhythmias
Muscle weakness, lid lag, stare, goiter
What is a significant risk factor which increases a hyperthyroid patient’s risk for Graves Ophthalmopathy?
SMOKING
Immunologic mediated
Everything turns green is the 1st sign of optic nerve traction
What would the lab evaluation of a PT with Hyperthyroidism look?
TSH screen (LOW)
Free T4, Free T3 (HIGH)
~~remember T3 more metabolically active~~
Thyroid Receptor Antibody (POS (+))
Radioactive Iodine (HIGH)Which drug is the of choice for 1st Trimester pregnancy PTs who suffer from hyperthyroidism or for thyroid storm.
PTU propothiouracil
increased risk of Liver Toxicity
What are some additional Anti-Thyroid drugs which you can Rx?
Tapazole
PTU
Organification of Iodide
Beta-blockers –> control adrenergic S/Sx
What might a PT present as to your clinic if they suffered from Subacute Thyroiditis?
You decide to order labs; what labs would you order and what values would you expect to see?
Pxful or Pxless
VIRAL mediated most likely (recent fever)
Hyperthyroidism –> may lead to –> Hypothyroidism
Sweating, tremor, palpitations
Stare, 166/60, P: 88, tender
Elevated ESR
TSH, T4, and T3 varies
Low 131I uptake in beginning
Fatigue Weight Gain Cold intolerance Dry Skin Swelling of the neck No prior Hx of HTN Edema Thyromegaly Decreased DTRs Bradycardia
Autoimmune Hypothyroidism (Hashimoto’s is Low)
MC in women –> lymphocytic infiltration of thyroid
Peroxidase antibody (+)
What is the clinical presentation of Hashimoto’s?
Fatigue, weight gain Cold intolerance Dry skin Thyromegaly Decreased DTRs Bradycardia Edema
What can cause Iodine excess?
Amiodarone
Kelp (seaweed)
What lab values will present with a HYPO-thyroid patient?
TSH is HIGH
Free T4 and free T3 LOW
What is the Tx for hypothyroidism?
L-thyroxine
~~Take on empty stomach
~~1/2 life is 7 DAYS
Follow TSH q two months
What is the clinical picture for Subclinical Hypothyroidism?
Fatigue Dry skin Joint stiffness TSH is slightly elevated T3 and T4 are normal
(+) peroxidase antibody test
MC in DM1 WOMEN
At what laboratory value will you decide to Tx a patient in respect to their TSH?
TSH over 10mU/L
Tx in less than 10 when…
- Pregnant
- Goiter
- (+) thyroid antibodies (peroxidase)
What is the 1/2 life of Amiodarone?
Why is this important?
What could it cause?
What would you use to counteract the effects of amiodarone?
100 days
High iodine can alter thyroid function and cause Thyroiditis (Hashimoto’s MC) or hypothryoidism
~~Inhibit T4 to T3 conversion
~~Block T3 receptor binding
~~Toxic to follicular cells
Tx with T4 (continue amiodarone)
What psychiatric drug must you always check for a goiter?
Lithium
Discuss the differences between Type 1 and Type 2 Amiodarone-induced Hyperthyroidism.
What would you Tx amiodarone induced hyperthyroidism with?
Type 1: HIGH T4 and T3
Pre-existing Graves, MNG (multi-nodular goiter)
Type 2: Destructive Thyroiditis
No new synthesis of T4 and T3
Methimazole –> TYPE 1
STEROIDS –> TYPE 2
Post-partum mothers should always be checked for their thyroid and related PE for what condition?
Postpartum thyroiditis
~~Thyroid inflammation and follicular damage (Flood gates opened and T4 and T3 are released unregulated)
~~Transitions to HYPOthyroid phase
What is the Tx for Postpartum Thyroiditis?
Hyperthyroid phase: beta blockers
Hypothyroid phase: Thyroid replacement
Annual TSH
EDUCATE –> Likely to happen w/ future pregnancies
During normal pregnancy what thyroid based changes from baseline can you expect?
TBG elevated; increases bound T4 and T3
Hyperthyroidism MC is Graves during preg
hCG can upreg thyroid stimulation
~~Hyperemesis gravidarum –> Hyperthyroid
What are 4 reasons T4 therapy for hypothyroid patients may need to be increased during pregnancy?
Increased T4 pool
High TBG
Placenta deiodinase (chews it up)
Reduced GI absorption (Fe in vitamins) must educate PTs to take medication at different time than prenatal vitamin
