Hyperprolactinemia Flashcards Preview

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Flashcards in Hyperprolactinemia Deck (21):
1

What is the most common disturbance of the pituitary

Hyperprolactinemia

2

What is hyperprolactinemia

Elevated serum prolactin (N levels

3

How many of women presenting with amenorrhea + galactorrhea are hyperprolactinemic

70%

4

Actions of prolactin

Acts to stimulate breast cell proliferation and induce milk production
Promotes formation of corpus luteum
Suppressed pulsatile secretion of GnRH
Inhibitory for spermatogenesis and steroidogenesis

5

How is prolactin secretion controlled

Inhibitory effect of dopamine-> D2 receptors on lactotroph cells
+by estrogen, TRH, VIP and oxytocin

6

Urgent considerations with prolactinoma

May rarely present as pituitary apoplexy

7

What is pituitary apoplexy, predisposing factors, clinical features and management

Clinical syndrome->infarction or hemorrhage of pituitary adenoma->extends rapidly to compress neighbouring structures

Predisposing: -ve pituitary blood flow, acute +blood flow (diabetes, HTN), +stimulation of gland through +estrogen states or pituitary testing, anticoagulated states

May be asymptomatic or sudden onset of headache, visual loss, nausea and vomiting, cranial nerve palsies, hemiparesis, and impairment of pituitary function.

If extends into Subarachnoid space, can be accompanied by meningism
Can have shock due to secondary adrenal insufficiency

Mx: supportive->fluids, dexamethasone. If conservative doesn't work->transphenoidal surgical decompression

8

Red flags

Prolactinoma
Acromegaly
Hypothalmic mass compressing pituitary stalk
MEN1
Chronic renal failure

9

Overview of differentials

+Pituitary production
Disinhibition by compression of pituitary stalk
Dopamine antagonist

Physiological:
Pregnancy (+estrogen, oxytocin)
Breast feeding
Stress (+TRH)
Hypoglycemia, MI, surgery, exercise, sex, sleep

Drugs:
Metoclopramide
Haloperidol
a-methyldopa
estrogens
MDMA
Antipsychotics

Diseases:
Prolactinoma->micro or macro
Stalk damage->pituitary adenoma, surgery, trauma
Hypothalmic disease->craniopharyngoma, tumors
Hypothyroidism (+TRH)
Chronic renal failure (-ve excretion)
Cirrhosis

10

Most common causes

Prolactinoma
Primary hypothyroidism
Drug-induced
Macroprolactinemia
Pregnancy

11

Presenting features

Amenorrhea
Galactorrhea
Erectile dysfunction
Headaches

Low libido
Weight+
Vaginal dryness

Hypogonadism
Infertility
Osteoporosis

-ve LH/FSH, testosterone and estrogen

12

Diagnostic approach on detection of +PRL

Detailed history and examination
Exclude physiological causes
Extensive drug history

Examination:
VFD, cranial nerve neuropathies
Thyroids
CRF
Cirrhosis
Evidence of metabolic abnormalities
Pregnancy

Laboratory investigations:
LFTs
UEC, renal function
Thyroid
Pregnancy
Prothrombin, albumin

Imaging:
MRI->once physiological, drug induced and secondary hyperPRL excluded
If macroadenoma->investigate for hypopituitarism->ACTH, LH, FSH, GH, TSH, free T4, glucose tolerance test, cortisol, testosterone, estradiol, DHEAS, insulin-like growth factor 1

13

Why doe women experience decreased libido, sexual dysfunction, hirsutism and vaginal dryness, osteoporosis

Hypoestrogenemia

14

What are the physiological causes to exclude

Pregnancy (+estrogen, oxytocin)
Breast feeding
Stress (+TRH)
Hypoglycemia, MI, surgery, exercise, sex, sleep

15

Most appropriate time to measure prolactin levels

At least 1 hour after patient has awaken/eaten

16

How to avoid pulsatile secretion

2-3 samples separated by at least 15-20 minutes

17

What is the diagnosis when physiological, drug induced and secondary hyperprolactinemias have been excluded and no lesion is detected on MRI

Idiopathic hyperprolactinemia

18

Management

Treat underlying cause

Dopamine agonist->bromocriptine= -ve PRL secretion, reduction in tumor size and restoration of mestural cycle
(alternative is cabergoline->less SE, more effective, unknown safety in pregnancy, can cause fibrosis)

If intolerant to dopamine agonist therapy->transphenoidal surgery->risk of permanent hormone deficiency and prolactinoma recurrence

19

Side effects of bromocriptine

Nausea
Depression
Postural hypotension

20

When is surgery indicated

Visual symptoms
Pressure effects
Failure of medical therapy

21

Follow up

Monitor prolactin
If headache/visual loss check fields and consider MRI
Medication is decreased after 2 years
Monitor carefully