Brainscape's Knowledge GenomeTM

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


See full index

(C) CM 1A: Heme/Onc/Endo > Lecture 17: Anterior Pituitary Disorders > Flashcards

Lecture 17: Anterior Pituitary Disorders Flashcards

1
Q

What artery supplies the anterior pituitary gland?

A

Superior hypophyseal artery

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

What are the 5 types of endocrine cells in the anterior pituitary? What do they secrete?

A
  • Somatotrophs: GH
  • Lactotrophs: LH
  • Gonadotrophs: LH & FSH
  • Corticotroph: ACTH
  • Thyrotroph: TSH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does a GH deficiency present in general?

A

Growth disorders in children
Abnormal body composition in adults

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

How does a Gonadotropin deficiency present?

A

Menstrual disorders and infertility in women.
Decreased sexual function, infertility, and loss of secondary sex characteristics in men.

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

How does a TSH deficiency present?

A

Hypothyroidism

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

How does an ACTH deficiency present?

A

Hypocortisolism

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

How does a Prolactin deficiency present?

A

Failure of lactation

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

What primarily inhibits prolactin?

A

Dopamine

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

How does prolactin inhibit itself?

A

Release of prolactin can cause a release of dopamine, so it is a negative feedback loop.

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

When is prolactin secretion highest?

A

non-REM sleep, usually 4-6am.

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

When are PRL levels the highest?

A

Pregnancy

10x increase

Declines rapidly within 2 weeks of parturition.

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

What keeps PRL levels elevated post pregnancy? How?

A

Breast-feeding.
The sucking causes a decrease in dopamine.

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

What hormone is responsible for the stimulation of milk release?

A

Oxytocin. PRL stimulates ADDITIONAL milk production.

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

What are the functions of PRL?

A
  • Induce/maintain lactation
  • Decrease reproductive function
  • Suppress sex drive
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does PRL inhibit reproductive function?

A

Suppresses hypothalamic release of GnRH and pituitary gonadotropin secretion and impairs gonadal steroidogenesis.

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

What is the most common pituitary hormone hypersecretion syndrome?

A

Hyperprolactinemia in both sexes.

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

What is the MCC of elevated PRL levels > 200?

A

PRL-secreting pituitary adenomas.

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

What is the mnemonic for hyperprolactinemia etiologies?

A

PROLACTINS
* Pregnancy
* Renal failure
* OCPs
* Liver failure
* Adenoma
* Chest wall disease
* Thyroidal disease
* Infiltrative disease
* Nursing/nipple stimulation
* Stalk effect

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

What are the hallmark signs of hyperprolactinemia in women?

A
  • Amenorrhea
  • Galactorrhea (80% of women)
  • Infertility
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the hallmark sign of hyperprolactinemia in men?

A

Hypogonadotropic hypogonadism

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

What other significant structure is extremely close to the pituitary gland?

A

Optic chiasm

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

When is the ideal time to measure PRL levels?

A

Fasting morning levels

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

What kind of tests can we run to exclude other DDx for hyperprolactinemia?

A
  • TSH/FT4 to r/o hypothyroidism
  • hCG
  • CMP
  • Men: serum total and free testosterone, LH, and FSH.
  • Women: serum estradiol, LH, and FSH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

When is a MRI indicated for evaluating hyperprolactinemia?

A

If we have a PRL > 200 or unable to find another cause.
Cannot detect microadenomas.

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

How do we treat hyperprolactinemia?

A
  • Normalizing PRL levels by finding the cause.
  • Microprolactinemias can be treated with estrogen, estrogen/progesterone, or testosterone.
  • Dopamine agonists
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the general medication for hyperprolactinemia regardless of cause?

A

Dopamine agonists.

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

What are the two dopamine agonists?

A
  • Cabergoline: long-acting
  • Bromocriptine: short-acting (when you want to be pregnant)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the main SE of dopamine agonists?

A
  • Constipation
  • Nasal stuffiness/congestion
  • Dry mouth
  • Nightmares
  • Insomnia
  • Vertigo
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What kind of patients do we need to be wary of when giving higher doses of cabergoline?

A

Parkinson’s. Risk of cardiac valve insufficiency.

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

How long do patients stay on dopamine agonists?

A

Usually a year.
Must resect adenoma for longer-term therapy.

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

Can you take dopamine agonists in pregnancy?

A

Yes if microadenoma.
Requires monitoring in macroadenomas if med stopped.

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

What is the only clinical manifestation of hypoprolactinemia?

A

Inability to lactate after delivery

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

What is sheehan’s syndrome?

A

Postpartum hypoprolactinemia due to necrosis of pituitary gland.
Often the result of severe hypotension or shock during delivery.

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

What are the causes of hypoprolactinemia?

A
  • Sheehan’s syndrome
  • Dopamine agonists
  • Tumors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

How do we treat hypoprolactinemia?

A
  • Dopamine antagonists
  • Surgery if tumor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What are GHIH, GH, and IGF-1?

A
  • GHIH = Growth hormone inhibiting hormone (Somatostatin)
  • GH = Growth hormone (Somatotropin)
  • IGF-1 = Insulin like growth factor 1 (Somatomedin)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What hormone does growth hormone do the opposite effect of?

A

Insulin

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

What does GH act on that releases IGF-1?

A

Liver and other organs, resulting in skeletal growth and cell growth.

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

What is the most abundant anterior pituitary hormone?

A

GH

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

What two things control GH secretion?

A

GHRH
Somatostatin

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

When is GH secretion the greatest?

A

Nighttime

42
Q

What increases GH levels?

A
  • Sleep
  • Stress
  • Exercise
  • Low BG levels
43
Q

As GH levels increase, what happens to IGF-1 levels?

A

Liver will secrete more IGF-1.

44
Q

What sex has higher IGF-1 levels?

A

Women

45
Q

What can cause GH deficiency?

A
  • Disruption of GH axis in either the hypothalamus or pituitary.
46
Q

What are the main etiologies for acquired GH deficiency?

A
  • Trauma
  • Infections (encephalitis, meningitis)
  • Cranial irradiation
47
Q

What is the main cause of mortality of children with GH deficiency?

A

Other hormone deficiencies, usually because of the CV changes from an altered body composition and dyslipidemia.

48
Q

How does isolated GH deficiency typically present?

A
  • Short stature
  • Micropenis
  • Increased fat
  • High-pitched voice
  • Hypoglycemia
49
Q

How can GH deficiency be inherited?

A
  • Autosomal dominant
  • Recessive
  • X-linked
50
Q

What can cause GH insensitivity?

A

Defects in GH receptor structure or signaling

51
Q

What lab tests diagnose GH insensitivity?

A
  • Normal/high GH levels
  • Low IGF-1 levels
52
Q

What is the main and only significant clinical manifestation of a GH deficiency?

A

Growth failure, which requires tracking of growth rate.
Use a growth chart!

53
Q

What criteria prompts us to evaluate for possible GH deficiency?

A
  • Short stature 2.5 SD below the mean
  • Height velocity < 25th percentile
  • Less severe short stature + growth failure without any other explanation.
  • Evidence suggesting hypothalamic-pituitary dysfunction
  • Evidence for deficits in other hypothalamic-pituitary hormones.
54
Q

What are other causes of growth failure besides GH deficiency?

A
  • Chronic systemic disease
  • Hypothyroidism
  • Turner syndrome
  • Skeletal disorders
55
Q

What lab tests should we order to help diagnose GH deficiency?

A
  • GH stimulation test
  • IGF-1
  • IGFBP3 (binding protein 3), carries IGF-1
  • Bone age
56
Q

What makes measuring GH production difficult?

A

GH secretion being pulsatile, since it is highest during sleep.

57
Q

How can we make our GH stimulation tests more useful?

A

Measuring IGF-1 and IGFBP3 also.

58
Q

Explain the process of a GH stimulation test.

A
  • Using either physiologic stimuli or pharmcologic stimuli
  • Must perform 2 different stimulation tests that both show subnormal GH secretion.
  • Must perform both after overnight fasts
  • Positive test = minor increases in GH at most.
59
Q

What imaging test could help us determine if there is a GH deficiency?

A

MRI to visualize the hypothalamus and pituitary.
CT of brain w/ contrast can screen for pituitary tumor.

60
Q

What is the treatment for GH deficiency?

A

Recombinant GH (0.02-0.05mg/kg/day)) SC

61
Q

What is the treatment for GH insensitivity?

A

IGF-1 to bypass GH receptors.

62
Q

What usually causes GH deficiency in adults?

A

Hypothalamic or pituitary somatotrope damage.

63
Q

What is the usual order of hormone loss with hypothalamic/pituitary damage?

A

GH => FSH/LH => TSH => ACTH

64
Q

What are the clinical features of AGHD?

A
  • Changes in body composition
  • Lipid metabolism
  • CV dysfunction
65
Q

What does body composition change look like in AGHD?

A
  • Reduced lean body mass
  • Increased fat mass
  • Increased waist-to-hip ratio
66
Q

What chronic conditions can occur with AGHD?

A
  • HLD
  • LV dysfunction
  • HTN
  • Increased fractures
67
Q

How do we test for AGHD?

A

Same as children. It is extremely rare though.

68
Q

What risk factors would prompt us to evaluate for AGHD?

A
  • Pituitary Surgery
  • Pituitary/hypothalamic tumor or granulomas
  • Hx of cranial irradiation
  • Radiologic evaluation of pituitary lesion
  • Childhood GH replacement therapy
  • Unexplained low age and sex-match IGF-1 levels.
69
Q

What are the CIs to treating AGHD?

A
  • Active neoplasm
  • Intracranial hypertension
  • Uncontrolled diabetes + retinopathy
70
Q

What is the dosing for recombinant GH for treating AGHD?

A

0.1-0.3 mg/d up to 1.25mg/d for IGF-1 level maintenance.

71
Q

What should we monitor when administering recombinant human GH?

A
  • Fundoscopic examinations for intracranial HTN
  • Adults: IGF-1 every 1-2 months, then semiannually
  • Children: Growth curve and PE with skeletal assessment every visit.
72
Q

What SE should we counsel pts on/watch out for when giving rHGH?

A
  • Fluid retention
  • Joint pain
  • CTS
  • Myalgias
  • Paresthesias
  • Hyperglycemia
  • DM
  • HA
  • Increased ICP
  • HTN
  • Tinnitus
  • Slipped capital femoral epiphysis
73
Q

What secretes GH from the anterior pituitary?

A

Somatotrophs

74
Q

What hormone inhibits GH secretion from the anterior pituitary?

A

Somatostatin

75
Q

What is the other name for IGF-1?

A

Somatomedin

76
Q

What is the treatment for GHD?

A

Somatotropin

77
Q

What is the cause of acromegaly/gigantism?

A

GH hypersecretion due to a somatotrope lesion usually.
Rarely an extrapituitary lesion.

Ectopic secretion has come from pancreatic, ovarian, lung, or hematopoeitic origins.

78
Q

What is the MCC of excess GHRH-mediated acromegaly?

A

Chest or abdominal carcinoid tumor.

79
Q

How does acral bony overgrowth typically appear?

A

GRADUAL
* Frontal bossing
* Increased hand and foot size
* Mandibular enlargement with prognathism
* Widened space between lower incisor teeth

80
Q

What kind of soft tissue changes occur due to swelling?

A
  • Heel pad thickness
  • Increased shoe or glove size
  • Ring tightening
  • Coarse facial features
  • Large fleshy nose
81
Q

What organs are typically enlarged with acromegaly/gigantism?

A
  • Cardiomegaly
  • Macroglossia (big tongue)
  • Thyromegaly
82
Q

What are the predominant clinical concerns with patients who have acromegaly/gigantism?

A
  • Cardiomyopathy with arrhythmias
  • LVH
  • Decreased diastolic function
  • HTN
83
Q

What other conditions can result from having acromegaly/gigantism?

A
  • Sleep apnea
  • DM
  • Colon polyps
84
Q

How much is lifespan generally reduced by excess GH levels?

A

10 years on average if left uncontrolled.

85
Q

What confirms the diagnosis of acromegaly?

A

Failure of GH suppression to < 0.4 mg/L within 1-2 hours of an oral glucose load of 75g. High glucose should stimulate somatoSTATIN release.

86
Q

What are the goals of treatment for acromegaly?

A
  • Controlling GH and IGF-1 hypersecretion
  • Ablate/arrest tumor growth
  • Restore mortality rate to normal
  • Preserve pituitary function
87
Q

What is the preferred primary treatment for adenomas in acromegaly?

A

Transsphenoidal surgical resection for both micro and macroadenomas.

88
Q

What is the adjuvant therapy for acromegaly?

A

External radiation therapy or high-energy stereotactic techniques

89
Q

What is the pharmacotherapy for acromegaly?

A
  • Somatostatin analogues
  • Dopamine agonists

Both can be combined.

90
Q

Which somatostatin analogue supresses gallbladder contractility?

A

Octreotide.
Suppresses postprandial gallbladder contractility and delays gallbladder emptying.

91
Q

What is the most common presentation of adult hypopituitarism?

A

Hypogonadism.

92
Q

How does hypogonadism present in females?

A
  • Oligomenorrhea
  • Amenorrhea
  • Infertility
  • Decreased vaginal secretions
  • Decreased libido
  • Osteoporosis
93
Q

How does hypogonadism present in males?

A
  • Decreased libido
  • Impotency
  • Infertility
  • Decreased muscle mass
  • Reduced beard/hair growth
94
Q

What labs help us evaluate hypogonadism?

A
  • Low gonadotropin levels with low sex hormone concentrations
  • IV GnRH should stimulate LH/FSH, causing increased serum levels. Abnormal response shows abnormal pituitary function.
  • MRI/other pituitary hormone tests
95
Q

In primary hypogonadism, what levels of GnRH, LH, and FSH would I see?

A

High for all.

Gonads not responding.

96
Q

In secondary hypogonadism, what levels of GnRH, LH, and FSH would I see?

A

Low for all.

Issue is in the hypothalamus/pituitary

97
Q

For males, what lab tests help evaluate hypogonadism?

A
  • Serum testosterone < 240
  • Free testosterone < 35
  • Serum LH and PRL levels
98
Q

For females, what labs help evaluate hypogonadism?

A
  • hCG (r/o pregnancy)
  • Serum PRL
  • Serum FSH and LH
  • Serum TSH
99
Q

For males, how do we treat hypogonadism?

A
  • Testosterone replacement
  • hCG (if infertile due to oligospermia)
  • Leuprolide/GnRH analog (if intact pituitary)
  • Clomiphene, stimluates pituitary gonadotropins.
100
Q

For females, how do we treat hypogonadism?

A
  • Cyclical replacement of estrogen and progesterone.
  • For ovulation: human menopausal gonadotropin (hMG) or recombinant FSH/LH
  • Pulsatile GnRH for hypothalamic infertility
101
Q

When is ACTH secretion at its peak?

A

6AM

(C) CM 1A: Heme/Onc/Endo (28 decks)

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