Pituitary Pathology - Krafts Flashcards
What hormones does the anterior pituitary secrete?
GH, ACTH, TSH, LH, FSH, and prolactin.
What hormones does the posterior pituitary store?
Oxytocin, ADH (vasopressin)
What five things can cause Hyperpituitarism?
- pituitary adenoma
- destruction of end organs
- hypothalamic disorders
- hyperplasia of anterior lobe
- carcinoma of anterior lobe
What are the clinical findings in a pt with Pituitary Adenoma?
None, at first (Common incidental finding)
Endocrine abnormalities (sometimes)
Mass effects: visual deficits, increased intracranial pressure, HYPOpituitarism
Rarely, can be “invasive”
Can bleed suddenly
What visual fields are impaired with a Pituitary Adenoma?
Loss of vision in bilateral lateral fields (temporal fields)
AKA = bitemporal hemianopsia
What is the microscopic appearance of a Pituitary Adenoma?
Sheets/cords
Uniform cells of one type
May be pleomorphic (bad, cells look different from each other)
May have mitoses
Can’t tell hormonal type
What is the most common secreting-type of Pituitary Adenoma? Least common?
Most common = Prolacting-producing
Least common = TSH-producing
What is a Prolactinoma?
Commonest type of pituitary adenoma
Efficiently secretes prolactin
What are the two main symptoms of a Prolactinoma?
Amenorrhea, galactorrhea
What is the treatment for a Prolactinoma?
Can treat with dopamine receptor agonists
What are the symptoms of a Growth Hormone Adenoma?
Gigantism (Pre-pubertal adenoma) => Very tall, Very very long arms, legs
Acromegaly (Post-pubertal adenoma) => Very tall, Enlarged bones of face, hands
What are some other manifestations of a Growth Hormone Adenoma other than getting tall/big?
Diabetes mellitus
Hypertension
Arthritis
Gastrointestinal carcinoma
What are the laboratory findings in a Growth Hormone Adenoma?
↑ GH (spurts)
↑ IGF-I (better)
GH unresponsive to glucose
What are the consequences of an ACTH Adenoma?
Makes ACTH
Cushing syndrome
Cushing disease (only when cushing syndrome due to ACTH adenoma)
Nelson syndrome (remove adrenals => no cortisol => no negative feedback => explosive growth of adenoma)
What are the five potential causes of Hypopituitarism?
Pituitary destruction
Ischemic necrosis
Empty sella syndrome
Pituitary apoplexy
Hypothalamic lesions
What causes pituitary destruction?
big pituitary adenoma (if they get big enough => compress remaining pituitary)
surgery or radiation
What happens in ischemic necrosis of the pituitary?
Pituitary gets BIG, blood flow stays same
Hemorrhage (delivery after ischemia) causes hypotension
Pituitary (already hypoxic) becomes necrotic
Pregnancy => sheehen syndrome?
What is Empty Sella Syndrome?
Arachnoid, CSF herniation
Pituitary compression
Usually NO hypopituitarism!
What is a Pituitary Apoplexy?
Sudden infarction of adenoma
Meningeal symptoms
Can be deadly (can look like a stroke)
What are the clinical findings in Hypopituitarism?
Insidious, chronic (HARD TO DX)
One or two hormones
Panhypopituitarism rare
GH, then FSH/LH, TSH, ACTH
What are the consequences of decreased GH, FSH, LH, PL, TSH, ACTH?
↓GH => pituitary dwarfism, pituitary dwarfism
↓FSH/LH=> loss of libido, menstrual abnormalities
↓PL => inability to lactate
↓TSH => hypothyroidism
↓ACTH => adrenal insufficiency
What is the two Posterior Pituitary Syndromes that we need to know?
- Diabetes Syndrome
2. SIADH
Diabetes insipidus
Central or nephrogenic ↓ ADH Pee dilute urine (would taste sweet) Serum osmolality increases Head trauma, tumors, alcohol consumption Increase water intake
Syndrome of Inappropriate ADH Secretion (SIADH)
↑ ADH Retain water Blood becomes hypotonic Usually mild, sometimes bad Ectopic ADH production (small-cell lung CA) Decrease water intake
