1. Thyroid Disease
Blake Briggs, Class of 2017

2. Introduction Remember the 4 B’s of the Thyroid
Brain development in utero
Increased Basal metabolism
Increased Beta adrenergic effects
Increased bone resorption
Noncancerous thyroid disease can be broken up into whether it is hyper or hypothyroid (AKA does it produce/release hormones or not)

3. Hyperthyroid diseases
Grave’s disease
Toxic multinodular goiter
Subacute thyroiditis
Struma ovarii
Presentation: remember that thyroid hormones increase beta adrenergic effects and basal metabolism. So all the symptoms and signs are based off these 2 concepts.
Tachycardia, palpitations, tremors, diaphoresis
Weight loss, diarrhea, polyuria

4. Grave’s Disease
Autoimmune disease where thyroid-stimulating immunoglobulins bind to TSH receptor and stimulate it, allowing for excess thyroid hormone production.
Unique sign: Exophalmos (bulging eyes)
Diagnosis: diffuse iodine uptake on nuclear imaging.

5. Grave’s Disease
Complication: Thyroid Storm. Massive release of thyroid hormones causes severe beta adrenergic effects. The most concerning complication is an arrhythmia. Other signs are high fever, agitation, nausea, and vomiting.
Tx: beta blockers, steroids, and PTU can save the patient’s life.

6. Grave’s Disease Treatment
Medical therapy: propylthiouracil (PTU) and methimazole block thyroid hormone production by inhibiting peroxidase.
Radioiodine ablation: best option. Administration of radioactive iodine that destroys follicular cells. Contraindicated in pregnancy.
Thyroidectomy: if ablation fails.

7. Toxic Multinodular goiter
”hot” nodules in thyroid release thyroid hormone. Due to Iodine deficiency  decreased T4  TSH induces thyroid cell hyperplasia and rapid “catch up” T4 production.
Dx: “patchy”, nondiffuse uptake of radioactive iodine tracer on nuclear imaging.

8. Subacute Thyroiditis (DeQuervain’s)
Post-viral infection; transient inflammation of thyroid gland.
Patient presents with fever and gland is painful to touch
Diagnosis: high serum thyroid hormone with negative radionucleotide uptake

9. Struma Ovarii Very rare. Ovarian teratoma produces thyroid hormone.
Diagnosis: high serum thyroid hormone with negative radionucleotide uptake. Thyroid is not enlarged and not painful to touch.

10. Hypothyroid diseases
Hashimoto’s
Iodine deficiency
Riedel’s thyroiditis
Lithium toxicity
Cretinism
Ablation
The opposite symptoms and signs of hyperthyroidism.
Decreased beta adrenergism: bradycardia, delayed reflexes, dry skin
Decrease basal metabolism: mental sluggishness, weight gain, constipation

11. Hashimoto’s disease
Autoimmune destruction of thyroid tissue. It is marked by hyperthyroidism at first, due to the targeting and destruction of follicular cells which release preformed thyroid hormone. Eventually, the cells are destroyed and less and less hormone is produced until no functional follicular cells are left.
Special findings: carpal tunnel syndrome, myxedema (pretibial and periorbital swelling)
Complication: Myxedema Coma- profound AMS  coma, hypotension, and hypoventilation.
Mainly from often untreated disease. Tx: hormone replacement, +/- intubation.

12. Riedel’s Thyroiditis
Progressive, irreversible inflammation and fibrosis of thyroid. Firm, hard, painless gland. Classically in young people. Due to autoimmune destruction and fibrosis.

13. Others
Cretinism: almost nonexistent in the US. Hypothyroidism in utero due to maternal hypothyroidism.
Poor brain development  mental retardation, umbilical herniation, short stature, delayed reflexes and hypotonia, jaundice, and macroglossia.

14. Thanks for listening
me with questions (even after I graduate):
Check out my review book: 201 Pathophysiology Questions
Students/dp/ /ref=redir_mobile_desktop?ie=UTF8&keywords=201%20patho physiology%20questions&qid= &ref_=mp_s_a_1_1&sr=8-1
Subscribe to my podcasts: