Pituitary and Hypothalamic Disorders Flashcards
6 Regulatory hormones of the hypothalmus
TRH: Thyrotropin releasing hormone GnRH: Gonadotropin releasing hormone CRH: Corticotropin releasing hormone GHRH: Growth hormone releasing hormone GHIH: Somatostatin PIH: Prolactin inhibiting hormone
Hormones of the anterior pituitary
FLAT PeG FSH LH ACTH TSH Prolactin GH
Most common cause of sellar masses?
Adenoma
Prolactinoma
Most common type of pituitary adenoma
Secretes prolactin
May compress optic chiasm = bitemporal hemianopsia
Prolactin inhibiting hormone?
Dopamine
If this cannot reach the pituitary because of a damaged stalk, prolactin levels will increase unchecked.
Medications that increase serotonin may lead to?
Increased prolactin levels
Antidepressants
Antipsychotics
Hypothyroidism may lead to?
Increased prolactin levels.
What does prolactin block?
Gonadotropins FSH and LH
Is a microadenoma more common in men or women?
Women
Macroadenomas (>1cm) are more common in men
S/S of prolactinoma in women:
Amenorrhea
Galactorrhea (milk w/o baby)
Infertility
S/S of prolactinoma in Men
Decreased Libido, gynecomastia, ED, infertility, bitemopral hemianopsia
Leads to decreased testosterone
Best test to dx prolactinoma?
Prolactin level
MRI to confirm
Tx for prolactinoma?
Dopamine agonists:
Cabergoline **
Bromocriptine
Surgery, chemo and radiation may be needed
Acromegaly
Excess growth hormone
Almost always caused by pituitary tumor
May also be ass’d with pancreas, paraT tumors
Acromegaly S/S
Skeletal changes Prominent brow, jaw protrusion Enlarged hands and feet Deepening of voice Carpal tunnel syndrome CHF Organomegaly Amenorrhea
Acromegaly Dx
IGF-1 level
Serum GH not suppressed following oral glucose load
MRI
Acromegaly Tx
Surgery
Or oral cabergoline
Gigantism
Excessive GH in children prior to closing of epiphyses
W/U and Tx same as acro…
Pituitary Apoplexy
Hemorrhage into the pituitary gland
Usually secondary to adenoma
HA, N/V, AMS, low BP, low glucose
Sheehan’s Syndrome
Post partum pituitary ischemic necrossi
Secondary to hypotension, emboli, HELLP syndrome.
DIfficulty breastfeeding, extended amenorrhea
First hormone deficiency to develop with lack if functioning pituitary? 2nd, 3rd 4th?
1: GH
2: LH/FSH
3: TSH
4: ACTH
S/S of LH/FSH deficiency
Amenorrhea, infertility, decreased pubic, axillary hair, genital atrophy, decreased libido, ED
S/S GH deficiency
Clinically undectable
S/S TSH deficiency
Fatigue, weight gain, weakness, decreased appetite, low BP, Low glucose
S/S ACTH deficiency
Fatigue, decreased appetite, decreased pigmentation, low BP, low glucose
Hypopituitary Dx
Test anterior hormones LH/FSH IGF-1 or GH glucose TSH ACTH (cortisol) MRI
Hypopituitary tx
Adress underlying cause
Replace needed hormone
Decompression may be needed for apoplexy
SIADH
Syndrome of Inappropriate ADH (too high) Euvolemic Hyponatremua **Elevated ADH Levels** Fluid is retained Low sodium, serum osmolarity
SIADH S/S
If chronic: asymptomatic
HA, N/ V
AMS
Seizures
SIADH Causes
TBI
Malignancy
Meningitis
Medications
SIADH Dx
CMP
Urine dip
High urine sodium, low serum sodium
Head CT
SIADH Tx
Increase serum sodium levels
Restrict fluids to 1200-1800 mL/day
Hyperotonic saline (3%) for symptomatic patients
1-2 ml/kg over 3-4 hours slowly
Diabetes Insipidus
Central:: Deficient levels of ADH Deficiency or resistance to ADH OR Nephrologic:: defect of renal tubules that interferes with water reabsorption
Diabetes Insipidus S/S
Elevated plasma sodium, inability to concentrate urine. Intense thirst (2-20L/day) Polydipsia. Polyuria, Nocturia Craving for ice water Hypernatremia
Diabetes Insipidus etiology
Central:: Most common: trauma or tumor Meningitis, radiation, idiopathic, cerebral anoxia Nephrogenic:: Meds: lithium, demeclyocycline Hypercalcemia, hypokalemia Sjogrens Syndrome
Diabetes Insipidus Dx
CMP
Plasma osmolarity
Plasma ADH
DDAVP Test
Diabetes Insipidus Tx
Central: DDAVP
Nephrogenic:
HCTZ or amiloride
Blocks reabsorption, keeps plasma sodium low
