Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ENRP Exam 2 > thyroid martin > Flashcards

thyroid martin Flashcards

1
Q

the thyroid gland consists of tow lateral lobes connected by the _

it is located blow and anterior to the _

A

isthmus

larynx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are some abberant locations of thyroid tissue

A

lingual, thyroglossal, substernal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

describe the HPA axis for thyroid

A
  1. stimulus like low body temperature will cause the hypothalmus to secrete TRH
  2. TRH stimulates the AP to secretes TSH
  3. TSH acts on the thyroid gland to release TH from the follicular cells
  4. TH through negative feedback stops the production of TSH and TRH when there are adquate levels
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

TH (thyroid hormones) essential action in a _ in basal metabolic rate

A

increase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

example of TH stimulation

A

increased fatty acid mobilization, increased heart rate, hypertrophy, increases cholesterol synthesis, increased gluconeogensis, increased protein catablism, increased growth, ,increased resportion of bone

decreased TSH and increased GH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Th _ growth hormone

A

increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

thyroglobulin is synthesized and stored in _. Iodide is transported into the cell and incorporated into TG (thyroglobulin) to form _ _ , TG is _ and cleaved to release _ and _

A

colloid

idodinated tyrosines

endocytosed

T4 and T3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

the thyroid is divided by thin _ into lobules there are about 20-40 lobules, they are lined by _ to _ _ epitheliun abd are filled with _ positive thyroglobulin

A

septae

low cuboidal (not active)

to low columnar epithelium (active)

PAS+ thyroglobulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

the thyroid follicle is formed by simple _ to low _ epithelium = follicular epithelium

A

cuboidal

columnar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

follicular cells aka _ cells produce

A

principle

T4 and T3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

_ induces follicular cells to transform from cuboidal to columnar

A

TSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

_ and _ regulate cell and tissue basal metabolism, _ production, and influence _ growth

A

T3 and T4

heat production

body growth/development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

follicles contain colloid what is a prinicple component of colloid?

A

thyroglobulin which is an idoniated glycoprotein (gel like substance)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

thyrogloblin is not a hormone is stores?

A

inactive form of thyroid hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

thryoid follicles convert thyroglobulin to _ and to a lesser amount of _

A

T4

T3 (lesser)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

_ and _ trasnport T4 and T3 to the periphery

A

thyroxine-binding globulin and transthyretin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

_ proteins keep T3 and T4 unbound or free in narrow limits

A

binding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

majority of T4 deionitaed to _ in the periphery which binds to thryoig hormone nuclear receptors with way greater affinity

A

T3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

multiprotein hormone receptor complex binds to _ in target genes regulating their transcription

A

thyroid hormone response element

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

upregulation of _ and _ catabolism plus stumulation of _ synthesis results in a new increase in basal metabolic rate

A

carbohydrate and lipid catabolism

protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

thyroid hormone has a critical role in _ development of fetus and neonate

A

brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

when the TSH reaches its TSH receptor in the thyroid what happens

A

Gs protein activation increased inctracellular CAMP which stimulated thyroid growth

T3 and T4 go to the thyroid hormone receptor and alter gene expression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is a goitrogen?

A

this is an inhbitor of T3 and T4 synthesis with an increase in TSH leading to a hyperplastic goiter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is propylthiouracil (PTU)

A

an antithyroid agent that inhibits oxidation of iodide

thus blocking thyroid hormone production

also blocks peripheral deiodination of T3 to T4 (getting rid of symptoms)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what does iodine adminsitration do?

A

it is adminsitered to people with hyperthyroidism and blocks the release of thyroid hormones

high doses of iodine inhibit proteolysis of thyroglobulin

Th is synthesized by not released

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what are parafollicular cells?

A

C cells that are in the periphery of follicular epithelium and lie on the basal lamina of the follicle(they are not expoased to the follicle lumen)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what do c cells look like (parafollicular cells)

A

pale staining, they are solitary cells or small clusters of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what do c cells secrete?

A

they secrete calctonin which lowers blood calcium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

how does calcitonin work

A

it lowers blood calcium levels. by suppressing osteoclastic activity and promoting calcium deposition in bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

secretion of calcitonin is directly regulated by?

A

serum calcium levels

if serum calcium levels are high they calcitonin is secreted to lower them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

thyrotoxicosis

A

this is a hypermetabolic state where there is hyperfunctionof the thyroid glands (increased T3 and T4)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

hyperthyroidism

A

overactive thyroid that releases preformed T3 and T4

can be used interchangeable with thyrotoxicosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

primary hyperthyroidism

secondary hyperthyroidism

A

primary: thyroid abnormality producing too much T3 and T4

secondary: extrinsic problem (too much TSH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what are the pathologies that have thyrotoxicosis (metablic state) and hyperthyroidism

A

primary: graves, toxic multinodular goiter, toxic adenoma, iodine induce hyperthyroidism, neonatal thyrotoxicosis associated with maternal graves disease

secondary: TSH secreting pituitary adenoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what are pathologies that are thyrotoxicosis only

A

granulomatous thyroiditis
subacute lymphocytic thyroiditis
struma ovarii
factitious thyrotoxicosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

hyperthyroid clinically is a hypermetabolic state and has overactivity of?

increased _ tone

A

sympathetic nervous system

increased B adrenergic tone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

skin in hyperthyroid

A

soft, warm, flushed

this is due to increased blood flow and peripheral dilation to facilitate heat loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what are symptoms of hyperthyroid

A

heat intolerance, weight loss, cardiac manifestations, neuromusclar changes, ocular changes, GI system and skeletal muscle changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what are the cardiac manifestations of hyperthyroid

A

increased cardiac output, tachycardia, palpitation, arrythmias, CHF, thyrotoxic/hyperthyroid cardiomyopathy

earliest symtoms of hyperthyroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what is thyrotoxic/hyperthryoif cardiomyopathy

A

reversible left ventricular dysfunction and low output heart failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

what neuromusclar changes are seen in hyperthyroid

A

termor, hyperactivity, emotional lability, anxiety

overactive sympathetic nervous system

**thyroid myopathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what is thyroid myopathy

A

a neuromusclar change that leads to proximal muscle weakness and decreased muscle mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

what GI tract changes are seen in hyperthyroid

A

hypermobility,malabsorption, hyperdefection

not diarrhea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

what ocular changes are seen in hyperthyroid

A

wide staring gaze, lid lag

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

true thyroid opthalmopathy is proptosis and is only in _ disease

A

graves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

what skeletal muscle changes are in hyperthroid

A

increased bone resorption and increase porosity so osteoporsis and fractures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

what other findings are consitent with hyperthyroid

A

fatty liver, lympoid hyperplasia, atrophy of skeletal mscule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

how do you diagnose hyperthyroidism

A

serum TSH

low TSH with high free T4 (primary hyperthyroidism)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

if TSH is normal or high and T4 is also high then this means?

A

pituitary associated (secondary )

if the TRH stimulation test normalizes high TSH then this excludes secondary hyperthryoidism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

radioactive iodine test

graves:

toxic adenoma:

thyroiditis:

A

graves: diffuse uptake

toxic adenoma: uptake in solitary nodule

thyroiditis: decreased uptake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

b blocker in hyperthyroid controls

A

symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

thionamide blocks

A

new hormone synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

iodine blocks

A

release of hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

radioiodine can be incorptiated into thyroid tissue and will ablate thyroid function over

A

6-18 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

graves is?

A

diffuse hyperplasia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

what is apethetic hyperthyroidism ?

A

older adults with hyperthyroisism that has masked symptoms

unexplained weight loss

57
Q

what is a thyroid storm

A

extreme and abrupt episode of life threatned thyrotoxicosis ( leakage of hormone)

58
Q

thyroid storm is abrupt and severe hypethryoidism that usually has underlying _ disease

A

graves

59
Q

in thyroid storm there is diffuse _ and enlargement of the thyroid which increases blood flow to the thyroid creating an audible _

A

hyperplasia

bruit

60
Q

what triggers thyroid storm

A

infection, surgery, stress!!!

stopping antithyroid medication

pregnancy/postpartum

61
Q

symptoms of a thyroid storm

A

wide, staring gaze, lid lag

exopthalmos (proptosis), corenal injury

pretibial myedema
weight loss
diarrhea
fever, tachcardia (disprportiant to fever)

62
Q

thyroid storm is a medical emergency and most people die of

A

arrythmias

63
Q

how do you diagnose thyroid storm

-scoring system

A

burch wartofsky score

64
Q

in apethetic hyperthyroidism there is thyrotoxicosis in the elderly and unexplained wight loss and worsening of _ issues

A

cardiovascular

65
Q

hypothyroidism prevelance increases with _ and is more common in _

A

age

females

66
Q

what is a goiter

A

thyroid enlargement

67
Q

what is the mutation in thyroid hormone resistance syndrome

A

THRB mutation

68
Q

what developmental cause would cause hypothyroidism

mutations

A

thyroid dysgenesis

PAX8
FOXE1
TSH

69
Q

what is autoimmune hypothyroidism

A

hasimitos thyroiditis

70
Q

what drug can cause hypothyroidism

A

lithium (for depression)

71
Q

what accounts for the majority of cases of hypothyroidism in high income countries

A

hasmimotos (autoimmune) and postablative hypothyroidism

72
Q

what is myxedema?

A

a symptom of hypothyroidism that presents with weight gain, cold intolerance, low cardiac output, mental sluggishness, dry brittle hair, thick tongue

73
Q

what are causes of congenital hypothyroidism

A

endemic iodine def. - most common

inborn erroer of thyroid metabolism

thyroid agenesis- no gland

thyroid hypoplasia - small sixe

74
Q

what is an inborn erroer of thyroid metabolism

A

a dyshormonogentic goiter that has thyroid hormone syntehsis defect

iodide transport
organification (binding to thyroglobulin)
T4 to T3 conversion

issues in any of these steps

75
Q

what are the two causes of inborn thyroid metabolism errors

A

thyroid peroxidase mutation

pendred syndrome

76
Q

what is pendred syndrome

A

congenital hyperthyroidism + sensorineural deafness

mutation in SCL26A4

77
Q

pendrin is a?

A

transporter of throcytes and in the inner ear

78
Q

germeline mutations in thyroid agensis

A

TTF-2, FOXE1, PAX8

79
Q

what is the TSH receptor germline mutation

A

thyroid nodules contain activating somating mutations of TSHR

80
Q

what antiboides are in hasimotos thyroidits ( autoimmune)

A

anti-microsomal, anti-thyroid peroxidase, anti-thyroglobulin

presents with a goiter

81
Q

hasimotos syndrome can sometimes be seen in conjunction with?

A

APS type 2

82
Q

what is thyroid hormone resistance syndrome mutation

affect

T4, T3, TSH levels

A

rare, autosomal dominant

mutation in THRB: thyroid hormone receptor mutation

so the hormone cant bind the receptor

increased T4 and T3 and TSH

resistance to hormone

83
Q

iatrogenic hypothyroidism is acquired what treatments can cause this (surgery/drugs)

A

thyroidectomy

radioiodine
methinmazole, PTU
lithium

84
Q

secondary hypothyroidism is usally central and can be caused by?

A

pituitary tumor, sheehan syndtome, hypothalamic damage

85
Q

symptoms of hypothyroidism

A

creatinism and myxedema

86
Q

what is cretinism

A

hypothyroisim in infancy that causes mental defects

87
Q

what is myxedema

A

hypothyroidism in older children or adults

“cretinoid state”

88
Q

cretinism is common in areas with?

A

iodine def endemics

89
Q

what casues creatinism

A

dyshormonogenetic goiter

iodine def

in infancy

90
Q

creatinism severity of impairement is dependent upon

A

timing of iodine def in utero

91
Q

maternal t3 and t4 cross the placenta and this is critical for fetal brain development, if maternal hypothyroidism occur before fetal thyroid development there is _ brain def

if it is after fetal thyroid development then the _ fetal brain fxn

A

severe

normal

92
Q

creatinism features

A

severe intellectual disability
short stature
coarse facial fatures
protruding tongue
umbilical hernia

93
Q

thyroid hormones regulate transcrption of several _ genes whose products are critical to maintaining efficent cardiac output

A

sarcolemmal

94
Q

hypothyroidism promotes a _ proflie

A

atherogenic

increases LDL and cardiovascular mortality

increases accumulation of matrix substanes (mucin) in the skin

95
Q

symptoms of myxedma

A

can present later

increased LDL
skin accumulation deposits: warts
non pitting edema, coarse facial features, thick tongue
deepening voice

slowing of physcial and mental activity

cold intolerance, cool skin, reduced cardiac output, consipation, decreases sympathetic activity

96
Q

inital symptoms of myxedma minmics?

A

depression

97
Q

unxplained increase in body weight and hypercholesterolemia should be assessed for

A

hypothyroidism

98
Q

testing for hypothyroidism

A

TSH screening

increased TSH in primary hypothyroisim decreased levels of hypothyroidism

99
Q

in hypothyroidism due to hypothalamic or pituitary disease what is TSH levels

A

normal/low

100
Q

what is thyroiditis

A

acute illness of the thyroid with severe pain, sudden onset of gland tenderness, fever, chills

101
Q

what are the three most common acute thyroditis

A

hasimotos
granulomatous thyroiditis
subacute lymphocytic thyroidits

102
Q

hasimotos thyroiditis is gradual thyroid failure due to _ destruction

A

autoimmune

103
Q

hasimoto thyroiditis is a major cause of _ goiter in pedatric populatoin

A

nonendemic

104
Q

what polymorphisms are associated with hasimoto

A

CTLA4
PTPN22
IL2RA

negative regulators of T cell responses

105
Q

dm type 1 and graves disease polymorphisms

A

CTLA4, PTPN22, IL2RA

associated with hasimotos because there is a break down in immune tolerance

106
Q

in hasimotos there is a breakdown of self tolerance to thyroid _ _

A

auto antigens

107
Q

what are the circulating antibodies in hasimoto thyroiditis

A

thyroglobulin and thyroid peroxidase

108
Q

hasimoto thyroditis is an induction of thyroid autoimmunity accompanined by progressive depletion of _ by apoptosis and replacement of thyroid parenchyma by _ and _

A

thyrocytes

lymphocytic iniltrate and fibrosis

109
Q

what are the three way antibodies kill thyrocytes in hasimoto thyroiditis

A

CD8+ cytotoxic T cell killing
cytokine mediated death (CD4+)
antibody medicated killing

110
Q

hasimotis histology

cut surface:

infiltrate:

follicles:

cellsK

A

yellow-tan on cut surface

minonuclear inflammatory infiltrate: lymphs, well developed germinal centers

atrophic follicles

hurthle cells

111
Q

what are hurthle cells

A

a metaplastic response of low cuboidal epithelium to chronic injury : eosinophilic!

112
Q

_ cells + heregenous population of _ = hashimotos

A

hurthle

lymphs

113
Q

clinical course of hasimotos

A

painless elnargment of thyroid and hypothyroidism develops gradually

decreased T3 and T4 , increased TSH

114
Q

what is hashitoxicosis

A

transient thyrotoxicosis that is caused by diruption of gollicles with release of thyroid hormones

brief change from normal (increased T3 and T4 and decreased TSH)

115
Q

hasimotos has an increased risk of?

A

b cell non hodgkins lymphoma and other autoimmune disorders (DM1, SLE, MG)

116
Q

what is subacute lymphocytic/post partum/painless thyroiditis

A

a painless thyroiditis that is an autoimmune disorder with antithyroif peroxidase antibodies

117
Q

in painless thyroiditis there is transient _ thyroidism but it is mostly _ thyroidism

there is a painless _ enlargement

A

hyperthyroidism

hypothyroidism

goiter

118
Q

in postpartum thyroiditis can resmeble

antibodies

A

graves disease

antithyroid peroxidase antibodies

normal thyroid without one year post partum

119
Q

painless and postpartum thyroditis are variants of _ thyroiditis

A

hasimotos

all have anti-thyroid peroxidase antibodies

1/3 of the cases can progress to hypothyroidism and resemble hasimotos

120
Q

histology of postpartum/painless/subacute lymphocytic thyroiditis

A

lymphocytic infiltration with hyperplastic germinal centers

no fiboris and no hurtlthle cells

121
Q

what is granulomatous thyroiditis = de quervain

A

thyroditis that is triggered by a viral infection.URI

it is painful

**peaks in summer

coxsackievirus, mumps, measles

122
Q

theory behind granulomatous thyroiditis

A

expsoure of viral or thyroid antigen released secondary to virus induced host damage, antigen stimulates CD8+ T cells that damage the thyroid

limited process- initiated by virus

123
Q

granulomatous causes a transient _ thyroid for 2-6 weeks and the will return back to normal function

A

hyperthyroidism

124
Q

serum for granulomatous thyroiditis

A

increased T4 and T3
decreased TSH
decreased radioactive iodine uptake

125
Q

histology of granulomatous thyroiditis

A

chronic inflammatory infiltrate with giant cells

126
Q

what is riedel thyroiditis?

what cells are involved

A

extensive fibrosis of the thyroid and surrounding neck structures

plasma cells and lymphocytes

127
Q

riedel thyroditis is a hard and fixed thyroid mass that stimulates _

A

carcinoma

128
Q

what antiboides are seen in riedel thyroiditis

A

igG4 and anti-thyroid antibody

129
Q

gross apperance of riedel thyroiditis

histology :

A

pale white color with replacement of thyroid tissue with fibrous tissue

histology: fibrosis

130
Q

what is the triad of graves disease

A

hyperthyroidism (diffuse)
exopthlamos
pretibial myxedema (scaly thicking over shins)

more common in women

131
Q

describe grave infiltrative opthalmopathy (exopthalmos)

A

there is in increase volune of the retro-orbital connective tissues and extraocular muscles
- infiltration by T cells
- -inflammation, edema and swelling
- accumulationof ECM (glycosaminoglycans)
- increase adipocytes

displacement of the eyeball and interefernce of extraocular muscles (tendons are spared)

132
Q

polymorphisms in graves

A

CTLA4, PTPN22, IL2RA

increase risk for other autoimmune disorders

133
Q

antibodies in graves

A

TSH (most important)
TSI (thyroid stimulating immunoglobulin)- most common
TSH receptor blcoing

134
Q

in graves disdease it is not unsual to see both stimulating and inhibiting igs in serum this explains episodes of _ in graves

A

hypothyroidism

135
Q

labs for graves

A

increased T3 and T4

decreased TSH

increased iodine uptake

high TSI ig

136
Q

histology of graves

A

diffuse hypertrophy and hyperplasia of the follicular cells

tall and crouded cells

small papillae that project into the follicular lumen

scalloped pale colloid

lymphoid infiltrate, generminal centers

137
Q

why are the margins of colloid scalloped and pale in graves

A

increased thyroglobulin utilization

actively resrob colloid in the centers of the follicles

138
Q

treatment of graves

A

B blockers

and reduce thyroid hormone synthesis

radioiodine ablation

surgical intervention

ENRP Exam 2 (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions