Lecture 18: Thyroid Disorders Part 2 Flashcards
What is thyrotoxicosis?
State of excessive T3/T4.
What is hyperthyroidism?
A state of increased thyroid function.
What is the most common demographic for hyperthyroidism?
Women > 60, esp if they smoke.
Same as hypothyroidism as well.
What is the MCC for thyrotoxicosis?
Graves disease (60-80%)
What is Graves Disease?
Autoimmune disorder in which autoantibodies bind to TSH receptors, causing excessive thyroid function.
What tests can be positive for Graves Disease?
- Thyroid stimulating Ig (TSI, 65% +)
- Anti-TPO (75% +)
- Anti-Tg (55%)
When is the most common onset of Graves Disease?
Women ages 20-40
What are TSI tests used for?
Assisting in the diagnosis of Graves Disease.
What is the first line test to check for Graves?
TSH/FT4/Thyroid panel
What can interfere with TSI lab tests?
Radioactive iodine
What are the common etiologies for excessive iodine in thyrotoxicosis?
- Iodinated radiocontrast dye
- High-iodine foods (kelp, nori)
- Potassium iodine, amiodarone, povidone iodine
What types of thyroiditis can cause thyrotoxicosis?
- Infectious/subacute
- Silent/postpartum
What are the general symptoms for thyrotoxicosis?
- Fatigue and weakness
- Weight loss with increased appetite
- Nervousness/restlessness
- Hyperactivity/irritability
- Palpitations/angina
- Muscle cramps
- Polyuria
- Diarrhea
- Heat intolerance and sweating
- Oligomenorrhea
What are the signs of thyrotoxicosis?
- Thin body habitus
- Agitation/restlessness
- Tachycardia
- AFib
- Muscle weakness, hyperreflexia, osteoporosis, fine resting tremors
- Goiter/thyromegaly
- Warm, moist skin
- Lid lag or lid retraction
What are the specific manifestations of Graves Disease?
- Graves Ophthalmology
- Thyroid acropachy
- Graves dermopathy
What does Graves Ophthalmology look like?
- Upper eyelid retraction
- Lid lag with downward gaze
- “Staring” appearance
- Conjunctival edema
What does thyroid acropachy look like?
- Digital clubbing
- Swelling of fingers and toes
- Periosteal reaction of extremity bones
What does Graves dermopathy/pretibial myxedema look like?
- Erythematous, rough plaques
- Lymphoid infiltration
What kind of cardiopulmonary manifestations can occur in Graves Disease?
- Forceful heartbeats
- Exertional dyspnea
- Abnormal conduction
- Cardiomyopathy
In what trimester of pregnancy is Graves Disease most common?
2nd trimester
Clinical
Why does Graves Disease see an improvement throughout pregnancy?
Physiologic suppression of the immune system.
Clinical
Divya is a 37-year-old female who was just diagnosed with primary hyperthyroidism. Assume she has not received any clinical interventions to treat her hormone status.
● What would we expect to happen to her T4 level?
● What would we expect to happen to her T3 level?
● What would we expect to happen to her TSH level?
● What would we expect to happen to her TRH level?
- T4 = elevated
- T3 = elevated
- TSH = decreased
- TRH = decreased
What lab abnormalities might we see in a primary hyperthyroidism patient?
- Hypercalcemia
- Elevated Alk phosphatase
- Anemic
- Decreased granulocytes
What lab is typically higher in thyroiditis over Graves Disease?
ESR