Pathology of the Thyroid Flashcards
WHat is Primary vs Secondary Hyperthyroidism
.
What are the Signs and Symptoms of Hyperthyroidism?
Hypermetabolism
Enhanced epinephrine effect
Lid Lag- delay in drop of eyelid when Pt looks down
Atrial Fibrillation-likely
Thyroid Storm- Thyrotoxic Crisis (exreme hypermetabolism)
What is the cause of Graves’ disease?
Autoimmune disease with prod of a IgG Ab against TSH receptor (TRAb) also (TSAb)
5:1 Fem to male ratio
How is Graves’ disease diagnosed?
High T3 and T4(may still be within normal range bc there is much variability)
Low TSH
What causes Opthalmopathy in Graves’ disease?
Lid Lag
Weak eye muscles
Ab against eye musc. and fibroblasts behind the eye
Excess Collagen and ground substance behind the eyeball
What are peripheral findings in Graves’ Disease?
Myxedema AND Nodules confined to the anterior aspect of the lower legs
What is seen grossly on the thyroid gland in Graves’ disease.
diffuse, symmetrical beefy red gland
What is the Histological apearance of the Thyroid in Hyperthyroidism?
1) Hyperplastic Follacles with papillary infoldings
2) Pale Colloid resorption vacuoles (scalloping)
What are the signs and symptoms of Hypothyroidism?
Slowing of Mind and Body
Mental slowness, fatigue, loss of interest
Myxedema => Coarsening of face, enlargement of tongue, puffy eyes, deepening and croaking voice
What is Myxedema?
Accumulation of hydrophilic ground substance (amorphous gel-like substance) throughout the connective tissue of the body
What is cretinism?
Hypothyroidism in infancy or childhood
Stunted Growth
Retarded mental devt
Delayed bone and tooth devt
What are the dangers of Cretinism?
If you do not treat before 3rd week there will be delayed Mental and physical devt. (Irreversible)
US babies are screened for Hypothyroidism
WHat is Hashimoto’s Thyroiditis?
Deficiency in Treg(regulatory T cells)
increase in cytotoxic T cells and activated B cells
HLA-Dr5
What is the Gross appearance in Hashimoto’s Thyroiditis?
Diffusely enlarged thyroid that is firm and light in color (WBCs)
What is the microscopic appearance of Hashimoto’s Thyroiditis?
Hyrthle cells
Abundant eosinophilic, granular cytoplasm
Metaplastic response to ongoing injury
What is De-Quervain (Subacute Granulomatous) Thyroiditis
Secondary to a viral infection to Coxsackie and Adenovirus also Echovirus and mumps Transient Hyperthyroidism (weeks to months) PAINFUL thyroiditis
What is the pathology of De-Quervain Thyroiditis?
Granulomas with giant cells macrophages, lymphocytes and destroyed thyroid cells
WHat is the effect of a goiter?
Thyroid’s ability to produce thyroid hormone is impaired => Inc TSH => Maint of euthyroid state
What is the Progression of a goiter?
Non-tender enlargement of gland => becomes nodular over time
What are the goiterogenic foods?
Cauloflower, Turnups, etc
What is a Multinodular Goiter?
Increaed size and lobulation of gland
Differentiate from neoplasm
What is the difference between Hot and Cold Nodules?
Cold: Palpable mass lesions that fail to take up radiolabeled Iodine (Higher chance of cancer)
Hot: Does take up Radiolabeled Iodine
What is a thyroid adenoma?
No tendency to turn malignant
Solitary sperical encapsulated lesion that is demarkated from the surrounding thyroid tissue
What is the most common type of thyroid cancer?
Papillary (65%)(prob. not die)
Follicular (25%) (50% will eventually die of it)
Medullary
Anaplastic (Almost all die quickly)
What is papillary Thyroid Cancer?
Fibrovascular Stal with tumor cells "Orphan Annie Eye" nuclei -marginated chromatin and optically clear centers -fixation artifact Coffee Bean (folded nuclei)
What is charicteristic of Follicular Thyroid Carcinoma?
Can Metastasise
What gene is Medullary Thyroid CA?
RET
What is Charicteristic of Anaplastic Thyroid CA?
Ugly on microscopic view -Large plieomorphic giant cells -Spindle Cells with SA appearance -Cytokeratin(+) but TG (-) and clinically too!
