Thyroid part II Flashcards
What are first signs subacute lymphocytic thyroiditis
mild hyperthyroidis,, goitrous enlargement of gland
demographics subacute lymphocytic thyroiditis
middle aged adults more common in women
postpartum thyroiditis and subacute lymphcytic (painless) thyroiditis are subtypes of what
autoimmune thyroiditis
must look into what with patient with painless thyroiditis
family history for autoimmune disorders
and look for antithyroid peroxidase Ab
what is difference morpho of hashimoto and painless thyroditis
no fibrosis or hurthle cell metaplasia in painless thyroiditis
progression of painless thyroiditis over 10 years
progress to hypothyroidism
what cna trigger granulomatous thyroiditis
viral infeciton, usually URI
coxsackie, mumps, measles, adenoa and other viral infections
describe radioactive iodine uptake in granulomaotus thyroidits
iodine uptake is diminished even though high T3 T4 and low TSH
extensive fibrosis of thyroid and contiguous neck structures
riedel thyroiditis
riedel thyroiditis is assoc with what
systemic autoimmune IgG4 disease
start at
thyroid neoplasm
what is the most common cause of impaired synthesis of thyroid hormone
dietary iodine deficiency
what occurs with impaired synthesis of thyroid hormone
goiter, enlargement of thyroid
what is a diffuse nontoxic goiter
enlargement without producing nodularity
where are areas of endemic goiters
in the mountains, low levels iodine
what food interfere with thyroid hormone synthesis
cabbage, cauliflower, brussel sprouts, turnips and cassava
sporadic goiters are more common in who
young females at puberty or young adult life
how does impairment of thyroid hormone synthesis lead to large thyroid
compensatory rise in TSH which causes hypertrophy and hyperplasia
what are the phases of diffuse nontoxic goiter
hyperplastic phase and phase of colloid involution
histo characteristics of colloid goiter
thyroid is brown and translucent, follicular epithelium is flattened cuboidal and colloid abundant
clincal Sx nontoxic/simple goiter
mass effects from enlarged gland
T3T4TSH levels in simple goiter
T3 T4 normal
TSH high normal
recurrent episodes of hyperplasia of the thyroid can lead to what
multinodular goiter
what is an intrathoracic or plunging goiter
when the thyroid grows behind the sternum
microscopic appearance of colloid rich follicles with inactive epithelium and areas of follicular hyperplasia
multinodular goiter
how to distinguish multinodular goiter from follicular neoplasm
absence of prominent capsule that is present in follicular neoplasm
what can a large multinodular goiter lead to
airway obstruction, dysphagia and compression of large vessels in neck and upper thorax (superior vena cava syndrome)
What is Plummer syndrome
toxic multinodular goiter when it starts to produce hyperthyroidism
radioiodine scan of a toxic multinodular goiter
uneven iodine uptake
what is a solitary thyroid nodule
palpable discrete swelling within an otherwise apparently normal gland
what is the concern for a person with a thyroid nodule
possibility of malignant neoplasm
majority benign10:1
what thyroid nodules are more likely to be neoplastic
solitary, nodules in younger patients
nodules in males
history of radiation
hot nodules (take up lots of iodine) are more likely to be benign or malignant?
benign
US can tell you what about thyroid mass
solid or cystic
most thyroid adenomas are what
follicular adenomas because derived from follicular epithelium
what is a toxic adenoma
an adenoma that produces thyroid hormones–> thyrotoxicosis
hormone production without stimulation
morphology follicular adenoma
solitary, encapsulated lesion demarcated by intact capsule
average 3 cm diameter
gray-white to red brown
areas of hemorrhage, fibrosis calcification and cystic changes
difference of follicular adenoma from carcinoma
carcinoma invades BM
Hurthle cell change
adenoma
lots of mitochondria, Tx aggressively
nonfunctioning adenomas appear how on radionucleotide scan
cold nodules
how is Dx made of thyroid adenoma
histologic examination of capsular integrity
Common types of thyroid carcinomas
papillary– majority!!
follicular
anaplastic (undifferentiated)
medullary
majority papillary carcinomas have what mutation
point mutation in BRAF signaling
some have RET translocation or inversion
follicular and anaplastic carcinomas have what mutations
RAS point mutation
PI3K point or amplification mutation
PTEN point mutations
majoirty of thyroid carcinomas are what
papillary
gray/white tumor
papillary carcinoma till proven otherwise
orphan annie nuclei (optically clear nuclei)
papillary carcinoma
psamomma bodies
papillary carcinoma
ovarian cancer
craniopharyngioma
patient with mass in cervical lymph node, otherwise asymptomatic
papillary carcinoma, isolated cervical mets no significance on prognosis
good test for distinguishing benign and malignant papillary carcinomas
fine needle aspiration
prognosis of papillary thyroid cancer
excellent
depends on age and distant mets
