EXAM #1: PATHOLOGY OF THYROID Flashcards
What are the signs and symptoms of hyperthyroidism?
1) Hypermetabolism
2) Enhanced epinephrine effect (tremulous and anxiety)
3) Lid lag
4) A-fib
5) Thyroid storm
What is “lid lag?”
A delay in the downward movement of the upper eyelid
A young female patient is sweaty with a-fib. What do you need to rule out?
Thyroid disease
What is thyroid storm?
- This is an acute, life-threatening, hypermetabolic state
- Induced by excessive release of thyroid hormones (THs) in individuals with thyrotoxicosis (Grave’s Disease)
Typically from surgery of childbirth
What is Graves’ Disease?
Autoimmune disease with production of IgG antibody vs. TSH receptor
What is the sex-predominance in Graves’ Disease?
Female
What are the labs that are seen in Graves’ Disease?
High T3/T4 with LOW TSH
What are the ophthalmologic consequences of Grave’s Disease?
Proptosis/ Exopthalmous
What is myxedema?
Swelling of the skin and underlying tissues of the shin giving a waxy/doughy consistency
*This is due to TSH stimulation of fibroblasts with TSHR
What is myxedema most commonly associated with?
HYPOthyroid–however, sometimes it is seen in HYPER; be sure to associate with other symptoms
*Iodine deficiency leads to increased TSH release OR, TSH antibodies in graves
What is the gross appearance of the thyroid gland in Grave’s Disease?
Diffuse, symmetrically beefy red gland
What is the histologic appearance of Grave’s Disease?
- Pale colloid with resporption vacuoles i.e. “scalloping”
- Hyperplastic follicles with papillary infoldings
What are the signs and symptoms of Hypothyroid?
1) Slowing of mind and body
2) Myxedema (accumulation of hydrophilic ground substance in connective tissue)
What is the name of the disease that occurs when a child has hypothyroid?
Cretinism
What are the clinical features of cretinism?
1) Stunted growth
2) Retarded mental development
3) Delayed bone and tooth development (2-4 months is normal)
Also, facial swelling, puffy eyelids, protruding tongue, low hair line, and altered eyebrows.
When does thyroid hormone need to be replaced to reverse the course of cretinism?
Before the 3rd week
*Note that legally you are abound to screen for cretinism
What is Hashimoto Thyroiditis?
Chronic progressive thyroid disease
*Presents as hyperthyroid then progresses to hypothyroid
What causes Hashimoto Thyroiditis?
Autoimmune destruction of the thyroid gland associated with HLA-DR5
What is the gross appearance of Hashimoto Thyroiditis?
- Diffusely enlarged
- Pale
- Intact
What is the histologically pathognomonic for Hashimoto Thyroiditis?
Hurtle Cells and chronic inflammation with germinal centers
What is a Hurtle Cell?
Metaplasia of the cells that line the thyroid follicle due to autoimmune attack
What is De Quervain Thyroiditis?
Transient granulomatous hyperthyroidism secondary to viral infection
What causes De Quervain Thyroiditis?
Viral infection esp. by coxsackie and adenovirus
What is the sex predominance of De Quervain Thyroiditis?
Female
What is the unique clinical aspect of De Quervain Thyroiditis?
PAIN/TENDERNESS
What is a Goiter?
Thyroid enlargement, usually due to relative iodine deficiency
What causes Goiter?
Impaired ability of thyroid to produce thyroid hormone
What happens to TSH with goiter?
Elevated
What causes Goiter?
Typically:
- Decreased iodide
- Compensatory increase in TSH leads to enlargement
What is a Colloid Goiter?
Beginning smooth goiter
What does colloid goiter progress to?
Nodular goiter
How will goiter appear histologically?
Colloid rich follicles with FLATTENED epithelium
What is the difference between hot and cold nodules? Why is it important to known the difference?
Hot= palpable mass that accumulates increased radioiodine
Cold= palpable mass that fails to take-up radiolabeled iodine
- More associated with adenoma and carcinoma
What is the next step in diagnosing a cold nodule?
Fine Needle Aspiration (FNA)
What is a thyroid adenoma?
Benign thyroid tumor
*Remember–if a female has thyroid adenome and a new problem it is very unlikley the tumor has turned malignant
What is the sex predominance of thyroid adenomas?
Female
What is the most common type of thyroid cancer? What is the prognosis?
Papillary= good prognosis
What is the type of thyroid cancer with the worst prognosis?
Anaplastic
*Nearly all die of it in a short time (3-6 months)
What is a major risk factor for papillary thyroid cancer?
Ionizing radiation
*Clinically this is associated with children that get radiation to the face for severe acne
What is a papillary carcinoma composed of?
Papillae lined by cells with
- Orphan Annie eye nuclei
- Nuclear Grooves
*Also, papillae are associated with psammoma bodies
What is a follicular carcinoma?
Malignant proliferation of thyroid follicles surrounded by a fibrous capsule with INVASION through the capsule
What is medullary carcinoma?
Malignant proliferation of parafollicular C cells
What does biopsy of a medullary carcinoma reveal?
Sheets of malignant cells in an amyloid stroma
What genetic mutation is medullary carcinoma associated with?
RET oncogene
What disorders is medullary carcinoma associated with?
MEN 2A and 2B
If a patient has a RET mutation, what surgical procedure is warranted?
Prophylactic thyroidectomy
What is an anaplastic carcinoma?
Undifferentiated malignant tumor of the thyroid
What patient population is anaplastic carcinoma typically seen in? What condition is this is stark contrast to?
Elderly vs. Riedel Fibrosing Thyroiditis* that is seen in younger patients
*This is chronic inflammation with extensive fibrosis of the thyroid gland–presents as hypothyroid with non-tender, “hard as wood” thyroid
