Pituitary tumors Flashcards
what visual pattern do you see with pituitary tumors
bitemporal hemianopsia
clinical presentation of acromegaly
changes in appearance, sizes for gloves, hats, rings, shoes
see carpal tunnel syndrome, hypertension, impaired glucose tolerance and OSA and increased risk for colon cancer
initial screening exam for acromegaly?
IGF-1 and if elevated next step is to do a glucose tolerance test and measure Growth hormone levels
diagnosis of acromegaly
positive IGF-1
then a impaired glucose tolerance test and high Growth hormone levels
treatment of acromegaly
surgical
if pt has prolactinoma then try medical management.
But if any loss of vision need surgery.
normal physiological causes of hyperprolactinemia
pregnancy, breast feeding and stress
pathological causes hyperprolactinemia
pituitary adenomas (prolactinomas)
hypothalamic dx with decreased dopamine (malignancy, sarcoidosis)
drugs (antipsychotics, metoclopramide)
hypothyroidism
chest wall injury (burns and herpes zoster)
chronic kidney disease
following a generalized tonic clonic seizure or focal seizure
what kind of seizures can cause an acute rise in prolactin?
generalized tonic clonic or focal seizure
pt has elevated prolactin and herpes zoster
chest wall injury can increase prolactin levels
what other endocrine disorder can be associated with high prolactin level?
hypothyroidism
due to stimulatory effect of TRH on prolactin as it’s trying to stimulate pituitary to release TSH.
what medications can cause an elevated prolactin level?
antipsychotics, metoclopramide
how does CKD cause elevated prolactin level?
it is not cleared as well and drop in 30% clearance. See a 3 fold increase in prolactin release (as a result of altered inhibitory effect of dopamine
mens symptoms of high prolactin
ED, decreased libido, infertility, gynecomastia, and rarely galactorrhea
pre menopausal women with high prolactin have these symptoms
galactorrhea and menstrual irregularities
can have amenorrhea
post menopausal women with elevated prolactin levels
asymptomatic.
what is screening test for acromegaly (first test)
IGF-1 level.
If elevated need to follow with a oral glucose suppression test.
if considering acromegaly and first IGF-1 was elevated, what test do you order to confirm this?
oral glucose suppression test.
If adequate GH suppression then not acromegaly
If inadequate GH suppression then you need to order a MRI of pituitary to look for a mass.
what does oral glucose suppression test look at?
test is (75 g oral glucose load) then measure GH hormone within 2 hrs
confirmatory testing for acromegaly since there was an elevated IGF-1 level.
A normal (non acromegaly pt) will have adequate GH suppression. GH decreases to <1 ng/ml
Someone with acromegaly will have inadequate GH suppression. GH levels <2 ng/ml
management of acromegaly with a pituitary mass
needs surgical management
could consider medical management
If pt has suspected acromegaly with (elevated IGF-1 and inadequate GH suppression) but MRI brain DOES NOT have a pituitary mass what to check next?
need to evaluate for extra pituitary cause of acromegaly (ectopic GH or GHRH secreting tumor)
presentation of acromegaly
new bilateral carpel tunnel syndrome
new skin tags, oily skin, excessive malodorous sweat and enlarging hands
OSA
how many people with acromegaly also have carpel tunnel syndrome?
about 20% incidence and likely from edema in the median nerve.
how to treat carpel tunnel induced acromegaly?
treat acromegaly and symptoms of CTS resolve.
Why do we check IGF-1 levels when concerned for acromegaly
because IGF-1 levels are consistently high in pts with acromegaly.
Don’t measure growth hormone levels because this can fluctuate in diurnal pattern and cannot be used to make diagnosis.
indications for treatment for prolactinoma female
females: classic symptoms of amenorrhea, galactorrhea,
infertility
acne and hirsutism
indications for treatment for prolactinoma male
hypogonadism, erectile dysfunction
gynecomastia
indications for treatment for prolactinoma for both sexes
enlargement of adenoma, mass effect symptoms
osteoporosis or increased risk for bone loss
Treatment of lactotroph pituitary adenomas or prolactinoma is dependent on
tumor size and metabolic complications
> 10 mm is a macroprolactinoma and needs tx
<10mm is a microprolactinoma and doesn’t need tx.
long term effects of not treating a microprolactinoma
Hyperprolactinoma causes gonadotropin secretion suppression and can cause low estrogen leading to infertility, amenorrhea, oligomenorrhea, vaginal dryness with dyspareunia and hot flashes. can also cause osteoporosis.
treatment of microprolactinoma
treat with cabergoline which can lower prolactin production and stop hypoestrogenic complications
untreated acromegaly clinical features of local tumor effect
pituitary enlargement visual field defects, headache, cranial nerve defects
untreated acromegaly clinical features of MSK/skin
gigantism, maloccluded jaw, arthralgias, arthritis, proximal myopathy
hyperhidrosis
skin tags
carpel tunnel syndrome
untreated acromegaly clinical features of: cardiovascular
cardiomyopathy, HTN, heart failure, valvular disease (mitral and aortic regurgitation)
untreated acromegaly clinical features of pulmonary and GI
OSA, narcolepsy, colon polyps and cancer and diverticulosis
untreated acromegaly clinical features of enlarged organs?
tongue, thyroid, salivary glands, liver, spleen, kidney and prostate
endocrine effects of untreated acromgely are:
galactorrhea, decreased libido, DM2, hyperparathyroidism and hypertriglycercidemia
acromegaly is at increased risk for:
colon, esophageal, gastric and melanoma
due to IGF1 stimulating the mucosal cell proliferation.
who has higher risk for developing cancer with acromegaly?
family history of colon cancer, age >50
male sex
longer duration of acromegaly
>3 skin tags
screening colon colonoscopy should be at
time of diagnosis and every 3-4 years after the age of 50 yrs
untreated acromegaly also has a higher risk for
mortality for cardiovascular dx and cancer
hyperphosphatemia is seen in
acromegaly pts too due to IGF1 stimulation of renal tubular phosphate reabsorption
what is lymphocytic hypophysitis?
rare disease that is caused by inflammatory infiltration of the pituitary gland and marked by inflitration of the lymphocytes
seen in women and mostly those after pregnancy or post partum period
will have hypopituitarism and so needs testing.
Diagnosis of lymphocytic hypophysitis
MRI will show diffuse homogenous sellar mass with both an enlarged pituitary gland and largement of the pituitary stalk which looks “pear shaped”
lymphocytic hypophysitis presentation
mimic a pituitary adenoma and so see headache which can be severe, intractable and generalized or focal retroorbital or bitemporal.
see fatigue, lethargy and loss of libido, amenorrhea, dizziness, nausea and vomiting and DI
pituitary hypofunction from tumors in sella result from
compression of normal pituitary stalk
seen with craniopharyngiomas, Rathke cleft cysts, arachnoid cysts
hypophysitis is
diffuse enlargement of the pituitary gland
seen in infiltrative disorders like sarcoidosis, TB, lympohma and normal pregnancy.
for macroadenomas visual field testing should happen every
6-12 months.
prolactinoma present and pt is pregnant. what is preferred treatment
bromocriptin over cabergoline due to shoert acting
side effects of dopamine agonists (bromocriptine and cabergoline)
insomnia, constipation and nasal stuffiness and dry mouth
when do we transphenoidal surgical resection of prolactinoma?
if prolactinoma doesn’t respond to maximal drug therapy after several months of treatment
also can be done in women who want fertility and have masses >3 cm
what is macroprolactinemia?
benign condition that has NOTHING TO DO WITH A PROLACTINOMA
caused by preciptitation of IgG bound to prolactin.
