thyroid diseases

What is a toxic multinodular goiter?

focal patches of autonomous functioning thyroid tissue. 60% due to TSH receptor mutations. hot nodules are rarely malignant

What is the most common histology of a thyroid adenoma. How does it differ from follicular carcinoma?

follicular histology. No capsular or vascular infiltration (in contrast to follicular carcinoma)

what causes hyperthyroidism early in hashimoto disease?

follicular rupture

what is the histology of de quervain disease?

granulomatous inflammation

what thyroid disease is lymphoma associated with?

hashimoto

what is the most common cause of hypothyroidism?

hashimoto thyroiditis

how does follicular carcinoma metastasize?

hematogenously

what are the labfindings in primary hypothyroidism

high TSH. low T3 and T4 hypercholesterolemia due to decreased LDL receptor expression

Whta are the finding in physical examination and histology in hashimoto disease?

hurthle cells, lympoid aggregates with germinal centers. moderately enlarged nontender goiter

What are the clinical findings of de quervain disease?

hyperthyroid early in course followed by hypo

which patient group does the undifferentiated anaplastic carcinoma occur mostly? what is its prognosis

older people. poor prognosis

what is the most common thyroid cancer? What is its prognosis?

papillary carcinoma. excellent prognosis

what does medullary carcionoma look like microscopically?

parafollicular cells in amyloid stroma which stains with congo red

how does papillary carcionoma look like microscopically

empty appearing nucleus (orphan annie eyes), psammoma bodies, nuclear grooves

what cancer is there an incresed risk of in hashimoto disease?

non-hodgkin lymphoma (typically of B-cell origin)

what are the symptoms of hypothyroidism

- GI: weight gain, decreased appetite, constipation - Psych/neuro: hypoactivity, fatigue, lethargy, weakness, decreased reflexes - muscle: hypothyroid myopathy (proximal muscle weakness) - skin: myxedema (facial/periorbital), cool, coarse, brittle -cardiac: bradycardia, dyspneu on extertion - other: cold intolerance

What are the symptoms of hyperthyroidism?

- GI: weight loss, increased appetite, diarrhea - psych/neuro: hyperreactivity, insomnia, tremor, anxiety, increased reflexes - muscle: thyrotoxic myopathy (proximal muscle weakness with normal CK) - skin: pretibial myxedema (graves), periorbital edema, warm, moist skin, fine hari - cardiac: palpitations, chest pain, arrhytmias due to increased senisitivity of B-receptors - other: exophtalmus, heat intolerance

what are the complications of thyroid surgery?

- hypocalcemia due to removal of parathyroid glands - damage of the recurrent laryngeal nerve when ligating the inferior thyroid artery - damage of the superior laryngeal nerve when damaging the superior laryngeal artery

How can a thyroid storm be treated?

4P's propanolol (b-blockers), propylthiouracil, Prednisolon (corticosteroids), potassium Iodine

What are the symptoms of congenital hypothyroidism?

6P's: Pot bellied, pale, puffy face, protruding umbilicus, protuberant tongue, poor brain development

what is the pathofysiology of hashimoto disease?

Auto-immune disorder with antithyroid peroxidadase (antimicrosomal) and antithyroglobulin antibodies

what are parafollicular cells and what do they do?

C-cells: produce calcitonin

when does hyperthyroidism often present itself?

during stress (eg, pregnancy)

What are the clinical findings of riedel thyroiditis

Fixed, hard (rock-like), painless, goiter. fibrosis may exted to local structures (trachea, esophagus) mimicking anaplastic carcinoma, hypothyroidism in 1/3rd of patients

what is the most common cause of hyperthyroidism?

Graves disease

what are the causes of a smooth/diffuse goiter?

Graves, Hashimoto, iodine deficiency, TSH-secreting pituitary adenoma

what is genetics is hashimoto associated with?

HLA-DR5

which diseases are associated with riedel thyroiditis?

IgG4-related systemic disease (eg autoimmune pancreatitis, retroperitoneal fibrosis, noninfectious aortitis)

what mutations is medullary carcinoma associated with?

MEN 2A and 2B (RET muatotions)

Which mutation is follicular carcinoma associated with?

RAS

What is the pathofysiology of graves disease?

Thyroid stimulating Immunoglobulin (IgG; type 2 hypersensitivity) stimulates TSH receptors on thyroid and dermal fibroblasts (pretibial myxedema)

How does a thyroid storm present itself?

agitation, delirium, fever, diarrhea, coma, tachyarrhytmia, increased liver function tests

what is a thyroid adenoma?

benign solitary growth of thyroid. usually cold

when is there an increased risk of papillary carcinoma?

childhood radiation, RET or BRAF mutation

What is a thyroid storm?

complication when hyperthyroidism is incompletely treated or untreated and significantly worsens in acute stress (trauma, infection)

What is congenital hypothyroidism also called?

cretinism

what is the clinical presentation of de quervain disease?

increased ESR (BSE), jaw pain, tender thyoid

What causes exophtalmus?

infiltration of retroorbital space by acitvated T-cells --> increased cytokines like TNF-a, IFN-y --> increased fibroblast secretion of hydrophyilic GAGs --> increased osmotic musle swelling, muscle inflammation and adipocyte count

what does follicular carcinoma look like microscopically?

invasion in vessels and thyroid capsule

What are other causes of hypothyroidism?

iodine deficiency, goitrogens (amiodarone, lithium), wollf chaikoff effect (iodine 'intoxication')

what are the labfindings in primary hyperthyroidism?

low TSH. High T3 and T4. hyporcholesterolemia due to increased LDL receptor expression

what is de quervain disease?

self-limited disease often following flue-like illness

What is congenital hypothyroidism and what causes it?

severe fetal hypothyroidism. caused by: maternal hypothyroidism, iodine deficiency, thyroid agenesis, thyroid dysgenesis, dyshormonogenetic goiter

what is de quervain disease also called?

subacute granulomatous thyroiditis

what is riedel thyroiditis?

thyroid replacement by fibrous tissue with inflammatory infiltrate

What are the causes of a nodular goiter?

toxic multinodular struma, thyroid adenoma, thyroid cancer, thyroid cyst

what is the jod-basedow phenomomenon?

when a hyperthyroidism under iodine deficiency becomes clinical when Iodine is repleted