Term
| What is the pyramidal lobe of the thyroid? |
|
Definition
| remnant of thyroglossal duct |
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Term
| Where is ectopic thyroid tissue usually located? |
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Definition
| the base of the tongue (lingual thryoid) or other sites abnormally high in the neck |
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Term
| What organisms are involved in chronic infections that cause thyroiditis? |
|
Definition
| mycobacteria, fungi, pneumocystitis |
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Term
| When Iodine is sufficient, what is the msot common cause of thyroiditis? |
|
Definition
| Hashimoto's (Chronic lymphocytic thyroiditis) |
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Term
| a middle-aged (45-65) woman with enlarged, painless thyroid gland and hypothyroidism |
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Definition
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Term
| What do Hurthle cells look like, and where do you see them? |
|
Definition
abundant eosinophilic, granular cytoplasm
Hurthel cells line atrophic thryoid follicles |
|
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Term
| What do you see microscopically w/Hashimoto's? |
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Definition
parenchyma: mononuclear inflamm infiltrate containing small lymphocytes, plasma cells, well-developed germinal centers
hurthle cells (eosinophilic cytoplasm(
fibrosis/keloid-like
increased interstitial CT |
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Term
| What do you see grossly w/Hashimoto's? |
|
Definition
| diffuse enlargement, capsule intact, pale/yellow/tan firm surface, somewhat nodular |
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Term
| Describe the thyroid hormone level's in hashimoto's |
|
Definition
| transient thyrotoxicosis (hyperthyroid) from disruption/release of thryoid follicles, followed by gradual onset of hypothyroidism |
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Term
| Describe the thyroid hormone level's in hashimoto's |
|
Definition
| transient thyrotoxicosis (hyperthyroid) from disruption/release of thryoid follicles, followed by gradual onset of hypothyroidism |
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Term
| Patients with Hashimoto's are at risk for developing what? |
|
Definition
| other AI diseases, and B-cell non-Hodkin lymphomas |
|
|
Term
| Patients with Hashimoto's are at risk for developing what? |
|
Definition
| other AI diseases, and B-cell non-Hodkin lymphomas |
|
|
Term
| middle aged (30-50) female presents with neck pain (tender thyroid), fever, fatigue, anorexia, malaise |
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Definition
| subacute (Granulomatous, De Quervain) thyroiditis |
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Term
| If untreated, what happens to De Quervain Thyroiditis? |
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Definition
| it typically goes away in 2-6 weeks, but may be followed by asymptomatic hypothyroidism for 2-8 weeks after |
|
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Term
| What causes Subacute(granulomatous, De Quervain) Thyroiditis? |
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Definition
| a virus or thryoid Ag released secondary to virus-induced host tissue damage stimulates cytotoxic T cells, which then damage thryoid follicular cells |
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|
Term
| What is seen microscopically in subacute thyroiditis? |
|
Definition
early: scattered follicles may be entirely disrupted and replaced by neutrophils forming microabscesses
later: aggregations of lymphocytes, histiocytes, and plasma cells aroudn collapsed and damaged thyroid follicles; multinucleated giant cells |
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Term
| What is the triad associated w/Graves Disease? |
|
Definition
hyperthyroidism from hyperfxnl, diffuse enlargement of the thyroid
infiltrative opthalmopathy>exopthalmos
localized infiltrative dermopathy (pretibial myxedema) |
|
|
Term
| What genetic factors are assoc w/Graves? |
|
Definition
|
|
Term
| What is the most common endogenous hyperthyroidism? |
|
Definition
|
|
Term
| What is the etiology of graves |
|
Definition
autoantibodies against TSH receptor
TSI: causes release of thyroid hormone
TGI: causes thryoid follicular epithel prolif
TBII: prevent TSH from binding to TSH receptor (can stim or inhib thyroid cell fxn) |
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|
Term
| grossly: thyroid appears diffusely enlarged, smooth and soft with soft meaty appearance resembling normal muscle |
|
Definition
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|
Term
| When/why would you hear an audible bruit from the thyroid gland? |
|
Definition
| With Graves disease, there may be an increased flow of blood through the hyperactive glad, causing an audible bruit |
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Term
| When do you see pale colloid w/scalloped margins in the thyroid? |
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Definition
|
|
Term
| What causes the infiltrative opthalmopathy in Graves? |
|
Definition
volume of retro-orbital CTs and extraocular muscles are increased due to:
infiltration by T cells
inflamm edema and swelling of extraocular muscles
accum of ECM components (GAGs)
increased adipocytes |
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|
Term
|
Definition
| radioiodine ablation and/or surgery |
|
|
Term
|
Definition
An ingested substance that interferes with thyroid hormone synthesis
i.e. excessive calcium and vegetables belonging to brassica and cruciferae families (cabbage, cauliflower, brussel sprouts, turnips) |
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|
Term
| What is a dyshormonogenetic goiter? |
|
Definition
A hereditary(AR) enzymatic defect that can interfere w/thyroid hormone synthesis and cause a goiter
peak incidence at puberty |
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Term
| What forms a colloid goiter, and what is its appearance? |
|
Definition
| The involution phase of a diffuse, nontoxic goiter forms a brown, glassy, translucent cut surface |
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Term
| What can cause a diffuse nontoxic (simple) goiter? |
|
Definition
| iodine deficiency, goitrogens, hereditary enzymatic defects |
|
|
Term
| What can cause a diffuse nontoxic (simple) goiter? |
|
Definition
| iodine deficiency, goitrogens, hereditary enzymatic defects |
|
|
Term
| What causes a multinodular goiter? |
|
Definition
| recurrent episodes of hyperplasia and involution |
|
|
Term
| What makes a thyroid nodule more likely to be neoplastic? |
|
Definition
solitary
cold (do not take up radioactive iodine)
younger patients
males
history of radiation treatment |
|
|
Term
| What is the hallmark of follicular (thyroid) adenomas? |
|
Definition
| A well, intact capsule surrounding the tumor |
|
|
Term
| What is the most common type of carcinoma of the thyroid? |
|
Definition
|
|
Term
| What type of thyroid cancer accounts for the most inherited cases? |
|
Definition
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|
Term
| What is the major risk factor predisposing an individual to thyroid cancer? |
|
Definition
| exposure to ionizing radiation during the first two decades of life |
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Term
| Where are Orphan Annie eye nuclei seen, and what else can you see with these? |
|
Definition
| papillary thyroid carcinoma, can also see intranuclear inclusions or grooves, psammoma bodies |
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Term
|
Definition
| seen in papillary thyroid carcinoma |
|
|
Term
| What symptoms suggest advanced disease in papillary thyroid cancer? |
|
Definition
| hoarseness, dysphagia, or cough |
|
|
Term
| What factors determine prognosis of papillary thyroid cancer? |
|
Definition
| age (>40), extrathyroidal extension, presence of distant metastases |
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|
Term
| PTC gene activation is associated w/what type of thyroid cancer? |
|
Definition
|
|
Term
| What neuroendocrine neoplasm is derived from parafollicular (C) cells |
|
Definition
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|
Term
| point mutations in the RET protooncoge plays a role in which type of thyroid carcinoma? |
|
Definition
| familial and sporadic medullary carcinoma |
|
|
Term
| What do you see microscopically with medullary carcinoma? |
|
Definition
| nests of polygonal/spindle-shaped cells, acellular amyloid deposits |
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|
Term
| What type of cancer shows nests of polygonal/spindle-shaped cells microscopically? |
|
Definition
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