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What are Signs of Hyperthyroid disease?
Flushed moist skin
Thinning of hair
Proptosis, lid lag
Pretibial myxedema
Brisk DTR’s
Goiter
Tremor
What are symptoms of hyperthyroid disease?
weakness & fatigue
nervousness
muscle aches
weight loss
heat intolerance
palpitations
amenorrhea
diarrhea
List types of hyperthyroid disease
Grave’s disease
Toxic uninodular goiter
multinodular goiter
Jod-Basedow
Factitious
Drugs
Thyroiditis
Tumor
What is Pretibial Myxedema and where is it seen?
chubby ankles
edema at the bottom of tibia
looks bumpy, red, and squishy
seen with Grave’s disease (eyes too)
What are some drugs that can induce hyperthyroidism?
Iodine-containing contrast dyes
Amiodarone
Iodinated glycerol
Alpha-Interferon
Alemtuzumab (anti-CD52)
TH (T3, T4)
What are the advantages of surgery to treat hyperthyroidism?
Definitive
TOC - Malignancy
TOC - Respiratory or swallowing difficulties
Existence of CI’s to RAI/Thioamides
Non-compliant pt
What are the disadvantages of surgery to treat hyperthyroidism?
Risks of hypothyroidism
surgical risks
Cosmetic consequences
Must safeguard against Thyroid Storm
What are the advantages of Radioactive Iodine therapy for hyperthyroidism?
Definitive
Alternative for non-surgical candidates
Pts who fail or experience ADR to drug therapy
Pts in which disease recurrence would complicate other diseases
Non-compliant pt
What are the disadvantages of radioactive iodine therapy for hyperthyroidism?
Risk of hypothyroidism
CI in pregnant or nursing mothers
Concern of use in children
possible radiation thyroiditis
must safeguard against Thyroid Storm
What are the advantages of drug therapy for hyperthyroidism?
Noninvasive
Minimize chances of hypothyroidism
Use in pts with CI to surgery/RAI
What are the disadvantages of drug therapy for hyperthyroidism?
Not definitive treatment
possible medication SE
requires long term compliance
What is functional unit of the thyroid gland?
FOLLICLES
What are the key elements that function within the follicle?
Thyroglobulin (Tg)
Tyrosine
Iodine
Thyroxine (T4)
Triiodotyrosine (T3)
What are the 4 steps in natural thyroid hormone synthesis ?
Iodide Trapping
Organification
Coupling
Release
Which three processes of natural thyroid hormone synthesis do thioamides inhibit?
Organification
Coupling
Release
What is the MOA of thioamides?
Inhibit Organification and Coupling
Immunosuppressive effect? → good for graves
PTU- inhibits peripheral T4 conversion
What are the SE of thioamides?
Benign (rash, fever, GI issues, arthralgia)
Severe (agranulocytosis, hepatitis)
What is an important counseling point for thioamide therapy?
Must report fever, sore throat, flu-like symptoms
any potential infection get CBC w/ differential - help determine neutropenia
What are the two thioamides?
Propylthiouracil (PTU)
Methimazole (Tapazole)
When is PTU preferred and how is it dosed?
Preferred: Preganacy (1st trimester), lactation, thyroid storm
dosed three times daily & bitter taste
added MOA inhibits peripheral T4 conversion
When is Methimazole preferred?
Considered thioamide of choice
Longer T 1/2 & better compliance & no bitter taste
How is Methimazole dosed?
30-60 mg/d in 1-3 doses
can be taken once daily
Name three birth defects that can be caused my methimazole use in the 1st trimester?
Aplasia cutis (scalp defect)
Esophageal atresia (ends & doesn’t connect to stomach)
Choanal atresia (nasal passages blocked by tissues or cartilage
Which medication has greater protein binding Methimazole or PTU?
PTU
What thioamide is preferred in children with hyperthyroidism?
Methimazole
When is PTU considered?
pregnant women in their 1st trimester
pts w/ life-threatening thyrotoxicosis
pts with a toxic reaction to MMI or not candidates for RAI or surgery but require anti-thyroid therapy
What thioamide has increased chances of hepatitis?
PTU
What is the difference between hepatocellular vs cholestatic hepatitis?
hepatocellular: increase in transaminases and bilirubin
cholestatic: problem w/in billiary tract & harder to reverse bc theres an obstruction in the liver
What is the MOA of beta blockers?
manage sympathetic-mediated symptoms
inhibit peripheral T4 conversion
When would beta blockers CI and what is used instead?
asthma
COPD
CHF
Use CCBs diltiazem, or verapamil
What are advantages and disadvantages of beta blockers?
+: symptomatic control quickly & effective for preparation of surger/RAI
-: doesn’t help underlying thyroid disease & CIs
What is the MOA of Iodides?
Blocks TH release
Inhibits organification
Inhibit peripheral T4 conversion*
decrease gland size & vascularity
What are SE of Iodide therapy?
Allergic reactions
Dose-related toxicity (Iodism) → mouth irritation
Metallic taste
”Escape” phenomenon → thyroid hormone escapes short term
Name 3 preparations of Iodides?
SSKI (38 mg/drop) - better palatability
Lugol’s Solution (6 mg/drop)
Thyro-Block (potassium iodide 130mg)
What are advantages and disadvantages of Iodide therapy?
+: prompt effectiveness, effective adjunct for surgery
-: can’t use alone, escape, CI: pregnancy, pts with nodular goiter or adenomas prior to RAI (will just use to make more)
What is potassium iodide usually used for and what are the names it goes by?
radiation exposure
Iosat
ThyroSafe
Thyro Shield
What is an important clinical pearl for potassium iodide?
do not give prior to RAI therapy otherwise therapy is not effective because Wolff-Chaikoff effect
When should a patient be checked after starting TH replacement?
3-6 weeks in intervals early-on
How often are pts on TH replacement therapy checked once they reach a euthyroid state?
annually
What is the treatment of choice for Grave’s Disease and for how long?
Thioamides
18-24 months (try normalize slowly then see if in remission)
What percent of Grave’s pts have Grave’s ophthalmopathy?
50%
What part of the eye breaks down in 3-5% of patients threatening their sight?
corneal breakdown or optic neuropathy
What is the brand name for Teprotumumab?
Tepezza
What type of medication is Teprotumumab?
Humanized human monoclonal antibody
What is the MOA of Teprotumumab?
IGF-1R inhibitor (insulin growth factor receptor
decreases initiation of thyrotropin receptor & IGF-1R
How many doses are needed, how is it administered, and what is the cost?
8 Doses
Intravenous
18,200 per vial x 23 vials for treatment
What does Teprotumumab treat?
teary red eyes
Grave’s opthamopathy
What is the treatment of choice for Toxic Nodular Goiters?
RAI therapy → usually gets to euthyroid
Surgery
avoid Iodides - nodules just eat it up
What is the treatment of choice for thyroiditism?
usually self-limited
inflammatory → treat w/ NSAIDs or BB as needed
look for subsequent transient hypothyroidism - 10% of postpartum women
What is the treatment of choice for neonatal thyrotoxicosis?
Treat w/ thioamides or beta blockers
Prevalence is 1:100 births to mothers with a history of Grave’s disease (> chance of passing antibody to newborns)
Who receives testing for hyperthyroidism?
every newborn
What is the treatment of choice for Iodine-induced HTR disease?
from excessive iodine ingestion
d/c source of iodine -usually self-limited
What is the treatment of choice for thyrotoxicosis factitia?
Due to excessive TH administration
d/c or decrease dose of TH
What is the treatment of choice for a pituitary adenoma?
Requires neurosurgical resection
CT/MRI → plucked through nose
What is the treatment of choice for a subclinical hyperthyroidism?
usually don’t treat unless TSH <0.1 mL
What is the treatment of choice for a thyroid storm?
supportive therapy: fluids, fever, nutrition
Treat precipitating event
High dose PTU
Iodide therapy
Beta blocker therapy
IV Glucocorticoids → in case of Grave’s disease
