pituitary Flashcards
pituitary space occupying lesions can cause underproduction and overproduction what are examples of each
underproduction: hypopituitarism
overproduction:
1) gh-> (gigantism before fusion of epiphysis)
(acromegaly after fusion of epiphysis)
2) prolactin -> galactohrrhea, amenhorrea, erectile dysfunction
3) ACTH –> cushings disease
4) TSH-> hyperthyroidism
if a pituitary tumor is in optic chiasm what would happen
bitemporal hemianopia
if pituitary tumor in cavernous sinus
CN 3,4,6
ooculomotor
abducens
trochlear
what are symptoms in a patient with a tumor compressing cavernous sinus
3- ptosis, diplopia, pupil dilation
4- vertical diplopia difficulty looking downward
6- lateral rectus palsy- inability to abduct the eye
tumor in hypothalamic centers symptoms
obesity
altered apetite and thirst
precocious puberty
diff btwn microadenoma and macroadenoma
micro: <1cm (prolactin lvl and yearly MRI)
macro: > 1cm (prolactin lvl, yearly mri, TSH T4 LH FSH IGF )
what type of surgery is gold standard for pituitary tumors especially macroadenomas
transphenoidal surgery enter thru the sphenoid sinus
almost all pituitary tumors are malignant
T or F
false. most are benign
hypopituitarism meaning
low hormones produced in pituitary
causes of hypopituitarism
1)pituitay or hypothalamic tumor (compression-necrosis-dec hormone )
2)previous surgery /radiation of pituitary adenoma
3) sheehan syndrome, infiltrative process
clinical features of hypopituitarism depending on each hormone
GH- short stature in children, silent in adults, inc LDL, inc risk of heart disease
LH and FSH- loss of libido, amenorrhea, erectile dysfunction
ACTH- hypotension ( secondary adrenal insufficiency)
TSH- fatigue and tiredness (secondary hypothyroidism)
prolactin- no lactate
ADH- diabetes insipidus
MSH- dec skin and hair pigment
most likely cause of compression of pituitary in adults and children
in adults: pituitary tumor/adenoma
in children: craniopharyngiomas from rathkes pouch develop in anterior pituitary
what is cause of pituitary apoplexy
1) hemorrhage : often due to pituitary adenoma, benign tumor demand more blood so more pressure
2) infarction: sheehans syndrome during preg high demand for blood by pituitary cells and escessive blood loss during childbirth , pituitary cells die if not restored
what are symptoms of FSH and LH in hypopituitarism
in women : oligomenhorrea, amenhorrea, infertility
men : loss of pubic hair , reduce muscle mass
in hypopituitarism which hormones are depleted first
LH, FSH, GH
tx of hypopituitarism
hormone replacement therapy
tumor removal
what is kalman syndrome
it is a rare genetic conditions occurs due to defective migration of GnRH-releasing neurons from olfactory bulbs to hypothalamic preoptic nuclei +complete loss of smell
dec GnRH secretion and underdeveloped olfactory bulbs
dec GnRH
dec pituitary secretion of FSH LH
dec testosterone in male
dec estrogen Female
what does it show on imaging of sheehan syndrome
empty sella turcica
what is when pituitary gland is either located eccentrically or in some ppl pituitary atrophy
empty sella syndrome
what is a primary and secondary form of empty sella syndrome
primary: enlarged or malformed of sella turcica which surround pituitary gland so csf leaks in and fill sella turcica –> compression or atrophy of gland
secondary: small gland due to removal
causes of hyperprolactinemia
1)adenoma of pituitary ( prolactinoma, most common type)
2)primary hypothyroidism ( inc in TRH –> stimulate prolactin secretion)
3)acromegaly ( prolactin co-secreted w GH)
4)PCOS- more estrogen more release of prolactin)
5)Drugs
6)compressed pituitary stalk by suprasellar mass lesion causing disassociation and discontinued of dopamine delivery to ant pituitary –> loss of inhibitory factor
features of hyperprolactinemia
1)galactohrrea
2) hypogonadism: Female= amenorrhea, infertility, anovulation, dec libido, risk of osteoporosis
male=erectile dysfunction,dec libido, infertility,
3) headaches and visual defect
what is the diagnosis of hyperprolactinema
1) perform serum prolactin first
2) thyroid function test
3) rule out pregnancy - B-HCG
4) Kidney and liver function - disease eelvate prolactin
when is MRI done if hyperprolactinema is suspected
if high prolactin is confirmed
secondary causes excluded
patient not pregnant
