20-22 Pituitary, Adrenal, Thyroid Flashcards
1
Q
Front (Term)
A
Back (Definition)
2
Q
What inhibits prolactin secretions?
A
dopamine
3
Q
What does the posterior pituitary produce?
A
ADH, Oxytocin
4
Q
What nuclei in the hypothalamus produces ADH? and Oxytocin?
A
supraoptic, paraventricular
5
Q
What does the anterior pituitary produce?
A
FSH, LH, ACTH, TSH, prolactin, GH
6
Q
Nonfunctional tumors of the pituitary are almost always what type? what is the tx?
A
macroadenomas, transsphenoid resection
7
Q
What rx might cause a response in TSH and FSH/LH secreting pituitary tumors?
A
bromocriptine (dopamine agonist)
8
Q
What is the most common pituitary adenoma?
A
prolactinoma (mostly microadenomas)
9
Q
Prolactinoma macroadenoma of the pituitary should be resected if hemorrhage, visual loss, CSF leak or if pt wants what?
A
pregnancy
10
Q
Prolactinoma microadenoma of the pituitary should be resected if ____ unsafe or ineffective (is OK in pregnancy)
A
bromocriptine
11
Q
Gigantism is a sx of acromegaly. Name 2 more.
A
HTN, DM
12
Q
Name the acromegaly preoperative rx that inhibits the release of GH.
A
octreotide
13
Q
How can acromegaly be life-threatening?
A
cardiac sx (valve dysfunction, cardiomyopathy)
14
Q
Postpartum trouble lactating is usually the 1st sign of what syndrome?
A
Sheehan’s syndrome
15
Q
Craniopharyngioma is a caclified cyst, remnants of what?
A
Rathke’s pouch
16
Q
What syndrome occurs after bilateral adrenalectomy; increased CRH causes pituitary enlargement resulting in amenorrhea and visual problems?
A
Nelson’s syndrome
17
Q
Why is there hyperpigmentation in Nelson’s syndrome?
A
bilateral adrenalectomy causes increased ACTH, beta-MSH (melanocyte-stimulating hormone) is a peptide byproduct of ACTH
18
Q
What is the tx for Nelson’s syndrome?
A
steroids
19
Q
What syndrome is caused by adrenal gland hemorrhage that occurs after meningococcal sepsis infection; can lead to adrenal insufficiency.
A
Waterhouse-Friderichsen syndrome
20
Q
What is the arterial supply of the adrenal gland and what is their origin?
A
Superior adrenal - inferior phrenic artery
Middle adrenal - aorta
Inferior adrenal - renal artery
21
Q
What is the venous drainage of the adrenal glands?
A
Left adrenal vein goes to left renal vein
Right adrenal vein goes to inferior vena cava
22
Q
What percentage of abdominal CT scans show adrenal incidentalomas? what percentage are mets or primary adrenal tumors?
A
1-2%, 5%
23
Q
When is surgery indicated for asymptomatic adrenal mass?
A
ominous characteristics (nonhomongenous),
>4-6 cm,
functioning,
enlarging
24
Q
How often to follow up for asymptomatic adrenal mass?
A
every 3 mos for first year and yearly after that
25
What is the most common mets to adrenal?
lung CA
26
What is the workup for asymptomatic adrenal mass with a cancer history?
bx
27
What are the 3 layers of the adrenal cortex and what do they produce?
GFR
Glomerulosa - aldosterone (salt)
Fasciculata - glucocorticoids (sugar)
Reticularis - androgens/estrogens (sex)
28
What is the innervation to the adrenal cortex? and the medulla?
none, splanchnic nerves
29
What does 4 things does aldosterone affect in the kidney?
sodium resorption, secretion of potassium, hydrogen ions, and ammonia
30
What does excess estrogens and androgens by adrenals almost always indicate?
CA
31
What is the most common (90%) congenital adrenal hyperplasia?
21 hydroxylase deficiency
32
In 21 hydroxylase deficiency what hormone is produced in excess and what is the effect on BP?
increased testosterone causes precocious puberty in males and virilization in females. Is salt wasting so causes hypotension
33
What are the 2 treatments for 21 hydroxylase deficiency and 11 hydroxylase deficiency?
cortisol and genitoplasty
34
List the 3 types of congenital adrenal hyperplasia and their sexual development and BP sx.
21 hydroxylase deficiency causes precocious puberty in males virilization in females. It is salt wasting so it causes hypotension
17 hydroxylase deficience causes ambiguous genitalia in males at birth and is salt saving
11 Hydroxylase deficiency precocious puberty in males, virilization in females. Salt saving so it causes hypertension
21 hypotensive boy, 17 hypertensive girl, 11 hypertensive boy
35
What is the name of the syndrome with hyperaldosteronism?
Conn's syndrome
36
What are the two types of Conn's syndrome and their primary marker?
Primary disease has low renin (adenoma),
| Secondary disease has high renin (CHF, RAS, liver failure, diuretics, Bartter's syndrome - renin secreting tumor)
37
What is more common primary or secondary Conn's syndrome?
secondary
38
What is the #1 and #2 causes of primary hyperaldosteronism?
adenoma, hyperplasia
39
Localizing studies in hyperaldosteronesim include Localizing studies – MRI, and ___ (shows hyperfunctioning adrenal tissue; differentiates adenoma from hyperplasia; 90% accurate); ___ if others nondiagnostic
NP-59 scintigraphy,
| adrenal venous sampling
40
In the tx of hyperaldosteronism, hyperplasia is seldom cured (↑ morbidity with bilateral resection) Try medical therapy first with hyperplasia using ___, calcium channel blockers, and potassium. If bilateral resection is performed (usually done for refractory hypokalemia), patient will need ___ postoperatively
spironolactone,
| fludrocortisone
41
What is the number one cause of hypocortisolism?
withdrawal of exogenous steroids
42
What is the number one cause of hypercortisolism?
iatrogenic
43
In the diagnosis of hypercortisolism what is done first (most sensitive test)? What is done 2nd?
24 hour urine cortisol, low dose overnight dexamethasone suppression test
44
What is the dx if low-dose overnight dexamethasone suppression test results in low urinary cortisol?
Cushing's disease (pituitary adenoma)
45
What is the #1 non-iatrogenic cause of Cushing's syndrome?
Cushing's disease (pituitary adenoma)
46
What is the #2 noniatrogenic cause of Cushing's syndrome? what is its most common cause?
Ectopic ACTH, small cell lung CA
47
Cortisol is not suppressed with either the low-dose or high-dose dexamethasone suppression test, what is the most likely diagnosis?
ectopic ACTH
48
With ectopic ACTH resection of the primary tumor is the tx. What are two alternatives if resection is not possible?
medical suppression or bilateral adrenalectomy
49
Name the drug used for adrenocortical cancer with metastatic disease that is an adrenal-lytic
Op-DDD (mitotane)
50
What is the origin of the adrenal medulla?
ectoderm neural crest cells
51
Catecholamine production starts with tyrosine. What are the next 4?
dopa -> dopamine -> norepinephrine -> epinephrine
52
What is the rate limiting step in the production of catecholamines and what is the enzyme?
tyrosine to dopa, tyrosine hydroxylase
53
PNMT is the enzyme only found in the adrenal medulla. What does it doe?
converts norepinephrine to epinephrine
54
What is the only type of pheochromocytomas that will produce epinephrine?
adrenal
55
What is the most notable location for extra-adrenal neural crest tissue?
organ of Zuckerkandl
56
What are the 5 things in the 10% rule for pheochromocytoma?
malignant, bilateral, in children, familial, extra-adrenal
57
What type(s) of MEN syndrome are associated with pheo?
MEN IIA and IIB
58
Which side are most pheos on?
right
59
Extra-adrenal pheos are more likely what?
malignant
60
What type of scan is useful in finding the location of a pheo?
MIBG (noepinephrine analogue)
61
Why don't you use venography with pheo dx?
can cause hypertensive crisis
62
How do you control pressure in a pheo pt preoperatively?
alpha blocker (phenoxybenzamine) before beta blocker to prevent a hypertensive crisis from unopposed alpha blockade
63
What drug is used in the tx of pheo, inhibits tyrosine hydroxylase causing decreased synthesis of catecholamines?
metyrosine
64
What is an important step in the resection of a pheo?
ligate veins before manipulating tumor
65
Name 4 extra adrenal sites for pheo.
vertebral bodies, opposite adrenal gland, bladder, aortic bifurcation
66
Name the rare benign, asymptomatic tumor of neural crest origin in the adrenal medulla or sympathetic chain.
Ganglioneuroma
67
What is the origin of the thyroid?
1st and 2nd pharyngeal pouches
68
What is the blood supply of the thyroid with origins?
superior thyroid arter is the 1st branch off the external carotid artery,
inferior thyroid artery is off the thyrocervical trunk
69
What is the blood supply to the parathyroids and how should they be ligated in thyroidectomy?
inferior thyroid arteries, ligate close to thyroid to avoid injuring parathyroids
70
What is the blood supply to the thyroid isthmus that is occurs in 1% and its origin?
Ima artery arises from the innominate or aorta
71
What is the venous drainage of the thyroid and where do they drain?
Superior and middle thyroid veins drain into the internal jugular. The inferior vein drains to the innominate vien
72
Nonrecurrent laryngeal nerve arises directly from the vagus and occurs in 2-3%. Which side is more common?
right
73
The superior laryngeal nerve tracks close to what other structure?
superior thyroid artery but is variable
74
What is the innervation of the cricothyroid muscle and what does injury result in?
superior laryngeal nerve, loss of projection and easy voice fatigability
75
Where does the recurrent laryngeal nerve track?
runs posterior to thyroid lobes in the tracheosophageal groove. can track with inferior thyroid artery but is variable
76
What structures do the right and left recurrent laryngeal nerves loop around?
right loops around right subclavian, left loops around aorta
77
What does the recurrent laryngeal nerve innervate?
motor to all larynx except cricothyroid
78
Injury to recurrent laryngeal nerve results in hoarseness. What additional tx is need for bilateral injury and why?
needs emergency trach since bilateral injury can obstruct airway
79
What is the posterior medial suspensory ligament of the thyroid that is close to the RLNs and requires careful dissection?
Ligament of Berry
80
What is the molecule that stores T3 and T4 in colloid?
thyroglobulin
81
What is the most lateral posterior extension of thyroid tissue called? They can be rotated medially to find what structures? (left behind with subtotal thyroidectomy because of proximity).
Tubercles of Zuckerkandl
82
What is the name of the cells that produce calcitonin?
Parafollicular C cells
83
What is a long-term side effect of thyroxine treatment?
osteoporosis
84
Postthyroidectomy pt develops stridor. What do you do?
open neck emergently to remove hematoma, can result in airway compromise
85
Thyroid storm is most common after surgery in pt with undiagnosed ____?
Grave's disease
86
What are the following sx of?:
increased HR, fever, numbness, irritability, vomiting, diarrhea, high-output cardiac failure (most common cause of death)
Thyroid storm
87
Describe the Wolf-Chaikoff effect which is very effective for pts in thyroid storm.
Patient given high doses of iodine (Lugol’s solution, potassium iodide), which inhibits TSH action on thyroid and inhibits organic coupling of iodide, resulting in less T3 and T4 release
88
What is the first step in dx of asymptomatic thyroid nodule?
thyroid function tests
89
Asymptomatic thyroid nodule FNA shows cyst fluid. It is drained and it recurs, what next?
thyroidectomy or lobectomy
90
Asymptomatic thyroid nodule with normal TFTs what is the next step in dx?
FNA
91
Thyroid FNA shows colloid tissue what is the tx?
Low chance of malignancy (<1%), thyroidectomy or lobectomy if it enlarges
92
Thyroid FNA shows follicular cells, what next and what is the malignancy rate?
thyroidectomy or lobectomy (5-10% malignancy rate)
93
What percentage of thyroid nodules are benign?
85%
94
What next if a thyroid nodule FNA is indeterminate?
Radionucleotide study
95
Thyroid nodule FNA is indeterminate, radionucleotide study shows hot nodule, what next?
Give thyroxine for 6 months, if size does not decrease perform lobectomy
96
Thyroid nodule FNA is indeterminate, radionucleotide study shows cold nodule, what next?
thyroidectomy or lobectomy
97
Diffuse enlargement of thyroid without evidence of functional abnormality = nontoxic colloid goiter. What is the tx?
Tx: try to suppress with thyroxine; 131I (may be ineffective), thioamides, subtotal thyroidectomy or lobectomy on side of goiter if medical treatment ineffective
98
What is the name of the thyroid lobe that occurs in 10%, extends from the isthmus toward the thymus?
pyramidal lobe
99
What is the cyst that classically moves upward with swallowing?
thyroglossal duct cyst
100
What is the tx for thyroglossal duct cyst and why?
Resection, susceptible to infection and my be premalignant. (Also need to take midportion or all of hyoid bone along with the cyst)
101
What are the two main side effects of PTU and Methimazole?
aplastic anemia or agranulocytosis
102
What is the treatment for hyperthyroidism that is good for young pts, small goiters and mild T3 and T4 elevation?
PTU and methimazole
103
What is the treatment for hyperthyroidism that is good for pts who are poor surgical candidates or unresponsive to PTU?
radioactive iodine (131I)
104
When is the best time to operate in pregnant women with hyperthyroidism?
2 trimester due to decreased risk of teratogenic events and premature labor
105
What is the most common cause of hyperthyroidism and what is the pathophys?
Graves' disease, IgG antibodies to TSH receptor
106
What is the recurrence rate for tx of Graves' disease with thioamides, 131I, and subtotal thyroidectomy?
70%, 10%, 10%
107
Suspicious nodule in pt with Graves' disease, what is the tx?
bilateral subtotal or total thyroidectomy
108
What is the preop preparation for a pt with Graves' disease undergoing a bilateral subtotal or total thyroidectomoy?
Preop preparation: PTU or methimazole until euthyroid, β-blocker, 1 week before surgery, Lugol’s solution for 10–15 days to decrease friability and vascularity (start only after euthyroid)
109
What is the most common cause of thyroid enlargement?
toxic multinodular goiter
110
Sx of toxic multinodular goiter include:
cardiac symptoms, weight loss, insomnia, airway compromise;
What could precipitate sx?
contrast dyes
111
What is the tx for toxic multinodular goiter and single toxic nodule?
131I and thioamides; 131I can be less effective in some (inhomogeneous uptake by gland); subtotal thyroidectomy or lobectomy if medical treatment ineffective
112
What is the most common cause of hypothyroidism in adults?
hashimoto's disease
113
Why can a goiter develope in Hashimoto's disease?
lack of organification of trapped iodide inside gland
114
What usually precipitates DeQuervains's thyroiditis?
viral URI
115
What is the tx for De Quervains thyroiditis?
steroids, ASA
116
Rare condition of woody, fibrous component to thyroid that can involve adjacent strap muscles and carotid sheath • Can resemble thyroid CA or lymphoma (need biopsy) • Disease frequently results in hypothyroidism and compression. Tx is steroids and thyroxine. May need isthmectomy or trach.
Riedel's fibrous struma
117
What is the most common endocrine malignancy in the US?
thyroid CA
118
What is the most common type of thyroid CA?
papillary
119
What type of thyroid CA is the least aggressive, slow growing and has the best prognosis?
papillary
120
What is the prognosis in papillary thyroid CA based on?
local invasion
121
What type of thyroid cancer's pathology has psammoma bodies and ophan Annie nuclei?
papillary
122
Papillary thyroid CA less than what size can have a lobectomy instead of total thyroidectomy?
<1 cm
123
Papillary Thyroid CA with clinically positive cervical nodes or extrathyroidal tissue requires what additional tx?
ipsilateral MRND
124
Papillary thyroid CA with metastatic disease, residual local disease, positive lymph nodes or capsular invasion requires what addtional tx?
131I 6 weeks after surgery
125
When would you give XRT for papillary thyroid CA
unresectable or no response to 131I
126
What is the 5 year survival in papillary thyroid CA?
95%
127
Enlarged lateral neck lymph node that shows normal appearing tissue. What is it and what is the tx?
papillary thyroid CA with lymphatic spread, total thyroidectomy and MRND
128
What percentage of follicular thyroid carcinoma has metastatic disease at the time of presentation?
50%
129
What is the route of metastasis and most common site with follicular thyroid carcinoma?
hematogenous, bone
130
If thyroid nodule FNA shows just follicular cells, what is the chance of malignancy?
10%
131
Lobectomy for follicular cells on thyroid FNA. Pathology shows adenoma or follicular cel hyperplasia. What next?
nothing
132
What size thyroid lesions showing follicular CA need total thyroidectomy?
>1 cm
133
Follicular thyroid CA with clinically positive cervical nodes or extrathyroidal tissue involvement. What additional tx is needed?
ipsilateral MRND
134
Follicular thyroid CA > 1 cm or extrathyroidal disease need what tx in addition to thyroidectomy?
131I 6 weeks after surgery
135
What is the 5 year survival rate with follicular thyroid CA?
70%
136
What does the pathology show in medullary thyroid carcinoma?
amyloid deposition
137
What can be used to test for medullary thyroid CA? Causes increase in calcitonin?
Gastrin
138
From what cells does Medullary thyroid carcinoma arise and what do they secrete?
parafollicular C cells, calcitonin
139
What two other conditions should be screened for if medullary thyroid carcinoma is diagnosed?
hyperparathyroidism and pheochromocytoma
140
What are two sx of elevated calcitonin?
flushing and diarrhea
141
Tx for medullary thyroid carcinoma is total thyroidectomy with what other dissection?
central neck
142
Prophylactic thyroidectomy and central node dissection in MEN IIa or IIb patients at what age?
2 years
143
What can be monitored for disease recurrence in medullary thyroid carcinoma?
calcitonin
144
What is the 5 year survival in medullary thyroid carcinoma?
50%
145
What is the 5 year survival for anaplastic thyroid cancer?
0%
146
What types of thyroid CA is 131I effective?
papillary and follicular only
147
When do you give I 131?
4-6 weeks after surgery when TSH levels are highest
148
When are TSH levels highest?
4-6 weeks after surgery
149
Should you give thyroid replacement before treatment with I131?
No. This would suppress TSH and uptake of I131
150
What are the indications for I131?
papillary and follicular only, recurrent CA, primary inoperable tumors due to local invasion, tumors that are >1cm or have extrathyroidal disease (extra-capsular invasion, nodal spread, or mets)
151
What do you do for pts with papillary or follicular cell CA and mets?
perform total thyroidectomy to facilitate uptake of I131 to the metastatic lesions (otherwise all gets absorbed by the thyroid gland).
152
What are the side effects of I-131?
sialoadenitis, GI sx, infertility, bone marrow suppression, parathyroid dysfunction, leukemia.
