Lecture 86 - Pituitary Path Flashcards
what are the two regions of the Pit?
what is secreted from each?
embryological tissue origin of each portion?
alternate names for each portion
Anterior Pit: FLAT PiG
Dervied from Oral Ectoderm
Aka – Adenohypophysis
Posterior Pit: Vasopressin, Oxytocin
aka Neurohypopphysis
Derived from Neuroectoderm
you’ve determined that the pituitary is hyperfunctioning; what are the possible etiologies?
Adenoma - almost always
hyperplasia –
Null cell Adenoma – (non functional, but has mass effect)
name some etiologies of hypopituitarism
Cysts Apoplexy Empy Sella Syndrome Sheehan Syndrome DIC Sickle Cell Radx Brain injury
what is apoplexy of the pituitary; how does it present?
sudden hemorrhage of the pitutiary, in the setting of an adenoma; presents with HA
what is Empty SElla Syndrome ?
Herniation of arachnoidal tissue into the sella
FIRST AID: atrophy or compression of pit, often idiopathic, common in obese women
what is sheehan syndrome? how does it present?
ischemic infarct of the pituitary following post partum bleeding;
Usually presents with failure to lactate, absent menstruation, cold intolerance
young patient, brain tumor
gross path: machinery oil like cyst fluid
histo: pallisading
what kind of tumor is this? where does it originate from?
prognosis
Craniopharyngeoma
Benign tumor
Originates from cells of tooth remnants in Rathke’s Pouch
describe the histological findings of a pituitary adenoma? what is the difference between a micro and macro adenoma?
Micro 1 cm
Pituitary lacks nested archiecture (best seen with reticular stain) and appears uniform in its cell type
A patient appears to have large pituitary mass but only a mildly elevated prolactin… what is the etiology of the elevated prolactin?
stalk effect – normally there is a direct correlation between the size of a prolactinoma and the serum prolactin levels. This patient only has a mildly elevated prolactin, therefore its likely due to stalk effect (physical disruption of inhibitor dopamine signals) and not an adenoma of prolactin cells
Clinical symptoms of Prolactinoma?
Treatment of prolactinoma
Amenorrhea, galactorrhea, loss of libido, infertility
Treatment: Dopamine agonists (Bromocriptine, cabergoline)
treatment for GH excess
octreotide
what pitutary adenoma classically presents as a microadenoma ? why?
ACTH producing pitutiary adenoma — very symptomatic
cushing syndrome vs cushing disease?
syndrome - any hypercortisolism
Disease – hypercortisol specifically in the setting of ACTH producting pit adenoma
Eponymous histological finding for cushing’s disease?
Crook’s Hyaline (due to negative feedback of cortisol on non ACTH producing cells of the pitutiatary – cytoplasm becomes Cytokeratinized
pathology reports positive Immunohistochemistry of LH and FSH of a pituitary sample, but the patient is actually presenting with Gonadotroph deficeincy. what is going on?
Paradoxical Gonadotroph Deficiency –
some adenomas stain positive for LH/FSH, but are actually non functional. May be destroying viable FSH/LH producing tissue via Mass effect