Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
59 Cards in this Set
- Front
- Back
Where will a thyroglossal duct cyst most commonly be found?
|
Midline neck above the thyroid isthmus but below the hyoid bone
|
|
What can potentially develop from a thyroglossal duct cyst if it contains thyroid tissue?
|
Primary thyroid carcinoma
|
|
What are the 3 most common causes of hyperthyroidism?
|
1. Graves disease
2. Hyperfunctional multinodular goiter 3. Hyperfunctional thyroid adenoma |
|
What are the top 3 causes of Hyperthyroidism?
|
1. Graves disease
2. Hyperfunctional Multinodular Goiter 3. Hyperfunctional Thyroid Adenoma |
|
What are 4 less common causes of Hyperthyroidism?
|
-TSH secreting pituitary adenoma
-Thyroiditis -Struma ovarii -Factitious thyrotoxicosis |
|
What changes physiologicaly in hyperthyroidism?
|
Basal metabolic rate is generally increased
|
|
What is the best lab test for hyperthyroidism?
|
TSH
|
|
What will the TSH/T4 be in hyperthyroid usually?
|
Low TSH
High T4 |
|
When would both the TSH/T4 be elevated in hyperthyroidism?
|
If the cause is a TSH-secreting pituitary adenoma
|
|
What is a useful lab test for diagnosing hyperthyroidism in addition to measuring TSH/T4?
|
Radioactive Iodine uptake
|
|
What pattern of RAI uptake will be seen in
-Graves disease -Toxic adenoma -Thyroiditis |
Graves: diffusely increased uptake
Toxic adenoma: Increased uptake in just one nodule Thyroiditis: decreased uptake |
|
What are 4 causes of Primary hypothyroidism?
|
-Surgery/Radiation ablation
-Autoimmune disease -Inborn errors of thyroid metabolism -Drugs |
|
What is the autoimmune disease of primary hypothyroidism?
|
Hashimoto's
|
|
What is 2ndary hypothyroidism?
|
Decreased thyroid function due to pituitary failure
|
|
What causes tertiary hypothyroidism?
|
Hypothalamic failure
|
|
What is Cretinism?
|
Hypothyroidism in infants and young children
|
|
What is Cretinism usually caused by?
|
Dietary deficiency of iodine
|
|
What are 4 symptoms of Cretinism?
|
-Mental retardation
-Short stature -Tongue protrusion -Coarse facial features |
|
What is myxedema?
|
The constellation of findings in Hypothyroidism seen in older children and adults
|
|
What will the lab findings for TSH and T4 be in primary hypothyroidism?
|
T4 will be low
TSH will be high |
|
What will the lab findings for TSH and T4 be in secondary or tertiary hypothyroidism?
|
TSH will be low
T4 will be low |
|
What is Thyroiditis?
|
Inflammation of the thyroid gland
|
|
What is Hashimoto's Thyroiditis?
|
Inflammation of the thyroid gland leading to failure
|
|
What causes the gradual failure of the thyroid in Hashimoto's?
|
Autoimmune destruction
|
|
What clinical symptom is commonly seen in Hashimoto's thyroiditis?
|
Goiter
|
|
What is the avg age group and sex ratio seen with Hashimoto's thyroiditis?
|
45-65 yrs old
F: M = 10-20:1 |
|
How does the pathology of Hashimoto's start and progress?
|
CD4+ Thelper cells become sensitized to self antigens and initiate destruction of the thyroid
|
|
What are 3 cells that are stimulated by the CD4+ Th cells sensitized to self thyroid antigens?
|
1. CTLs
2. Th1 cells 3. Plasma cells |
|
What results from the CTL stimulation?
|
Fas/FasL interaction and cell-mediated cytotoxicity
|
|
What results from the Th1 differentiation?
|
Secretion of IFN-y and activation of macrophages for thyrocyte injury
|
|
What results from the Plasma cell stimulation?
|
Secretion of anti-thyroid antibodies for NK-cell mediated ADCC
|
|
Are the thyroid hormones always decreased in Hashimoto's?
|
No, initially they mey be elevated to inappropriate release due to the inflammatory destruction of the gland.
|
|
Do all cases of Hashimoto's end in hypothyroidism eventually?
|
Yes
|
|
Is the thyroid enlargement in Hashimoto's painful or painless?
|
Painless
|
|
What does Hashimotos thyroiditis increase the risk for patients developing? (6 diseases)
|
-Type I diabetes
-Autoimmune adrenalitis -SLE, myasthenia gravis, SS -Bcell NHL |
|
What are 2 other types of thyroiditis that cause HYPERthyroid function?
|
-Subacute Granulomatous Thyroiditis
-Subacute Lymphocytic Thyroiditis |
|
What are the main things to remember about Subacute Granulomatous Thyroiditis?
|
-Younger adults (30-50 yo)
-Postviral Upper resp infection -Neck PAIN -Self limited/complete recovery |
|
Despite the increased thyroid function, what will the RAI uptake be in SGT?
|
Decreased
|
|
In what patients is Subacute Lymphocytic thyroiditis most commonly seen?
|
Postpartum women
|
|
What are the 3 main things to remember about SLT?
|
-Post partum women
-NOT painful -Self-limited, may be asympmt |
|
What is Fibrous Thyroiditis often confused as? Why?
|
Carcinoma - because of extensive fibrosis that creates a hard and fixed thyroid mass.
|
|
What is the most common cause of endogenous hyperthyroidism?
|
GRAVES disease
|
|
What is the triad of clinical findings seen in Graves disease?
|
1. Diffuse enlargement of the thyroid causing Hyperthyroidism
2. Opthalmopathy 3. Infiltrative dermopathy |
|
What is the infiltrative dermopathy in Graves also called?
|
Pretibial myxedema
|
|
In what age /sex of patients is Graves most often seen?
|
Age: 20-40
Sex: Females 7: Males 1 |
|
What causes the thyroid hyperfunction in Graves?
|
Autoantibodies to the TSH receptor that stimulate it
|
|
What are the autoantibodies in Graves disease called?
|
TSI - Thyroid stimulating globulin
|
|
What type of immunoglobulin is the TSI?
|
IgG
|
|
At what other tissue site is the TSH receptor also expressed and thus stimulated by the TSI in graves?
|
Orbital preadipocyte fibroblasts
|
|
What is the effect that TSI stimulation of the TSH receptor on Orbital preadipocyte fibroblasts has?
|
Exopthalmosis
|
|
What happens to the exopthalmosis in Graves disease when treated?
|
It may go away, or may persist
|
|
How is Graves disease diagnosed?
-Lab findings -RAI uptake |
Lab: increased T3/T4, low TSH
RAI: diffusely increased |
|
What is a Goiter in general?
|
An enlargement of the thyroid gland from any benign cause
|
|
What is the most common cause of Goiters?
|
Dietary deficiency of iodine resulting in decreased circulating T3/T4, so upregulated TSH
|
|
What are the thyroid functionality most often in patients with goiters?
|
Euthyroid
|
|
What are the T3/T4/TSH levels usually in patients w/ goiters?
|
T3/T4 = normal
TSH = normal to sl high |
|
What type of goiter is seen in
-Young adults -Older adults |
Young: simple
Older: multinodular |
|
What is a complication that Nodular goiters can lead to?
|
Secondary hyperthyroidism due to toxic multinodular goiter
|
|
In what syndrome is Toxic multinodular goiter a component?
|
Plummer syndrome
|