Endo - Hypopituitarism Flashcards
(20 cards)
Anterior Pituitary Failure - how does this happen??????
Primary disease = glands fail (thyroid, adrenal cortex, gonads)
Secondary disease (no signals from hypothalamus or AP)
Primary Hypothyroidism?
Causes?
Low T3 and T4
High TSH
autoimmune destruction of thyroid gland
Secondary Hypothyroidism?
Causes?
ALL low
pituitary tumour damages thyrotrophs, much les common
Primary Hypoadrenalism?
Causes?
Low C
High ACTH
NOT aldosterone
(AI) destruction of adrenal cortex
Secondary Hypoadrenalism
Causes?
ALL low
pituitary tumour damaging corticotrophs
Primary Hypogonadism?
Causes?
Low T and O
High LH and FSH
Destruction of testes (mumps) or ovaries (chemo)
Secondary Hypogonadism?
Causes?
ALL low
pituitary tumour damaging gonadotrophs
Congenital causes of hypopituitarism - how?
RARE, usually due to TF gene mutations for AP development
Congenital causes of hypopituitarism - hormones?
Deficiency in GH and at least one other
Congenital Causes - signs?
Short stature
Hypoplastic AP on MRI
Acquired causes of hypopituitarism?
TTRIPPP
Tumours e.g. adenomas, metastases, cysts
Traumatic brain injury
Radiotherapy (hypothalamic/pituitary damage)
Infection e.g. Men
Inflammation (hypophysitis)
Pituitary surgery
Peri-partum infarction
Pituitary apoplexy
Hypopituitarism NOMENCLATURE
- any number of axes
- usualy AP, some processes esp INF or surgery can cause PP
- Panhypopituitarism = total loss of both
Radiotherapy-induced HypoP?
Both hypothalamus and pituitary sensitive to radiation.
GH and FSH/LH most sensitive.
Can be direct radiotherapy to P or indirect.
Higher dose (Gy) = higher risk of HPA axis damage
Risk up to 10yr after so annual assessment
Presentations of HypoP?
In terms of hormones
FSH/LH - 2 amenorrhea
ACTH - fatigue
TSH - fatigue, LT weight gain
GH - redcued QoL, short stature in children
PRL - inability to breastfeed
What is Sheehan’s syndrome?
PPH > hypotension > pituitary infarction > PP hypopituitarism
What happens to the anterior pituitary during pregnancy?
Enlarges (lactotroph hyperplasia)
Symptoms of Sheehan’s Syndrome?
By hormone deficiency
TSH/ACTH/(GH) - lethargy, anorexia, weight loss
PRL - failure of lactation
LH/FSH - failure to resume menses post-delivery
* weight loss due to cortisol deficiency
PP usually not affected
Why can it be difficult to diagnose Sheehan’s Syndrome?
Not red flag symptoms, a lot are comon after pregnancy
What is the best imaging for pituitary?
MRI as highest resolution
Pituitary is tiny and at base of skull
What is pituitary apoplexy
