Cushing syndrom Flashcards
(23 cards)
Endocrine disorders involve what?
Involve control by the anterior pituitary gland
What are the various degrees to endocrine disorders?
Primary - intrinsic malfunction of the hormone-producing target gland
Secondary - malfunction of the pituitary cells that control the hormone produce gland
Tertiary - malfunction of the hypothalamus
Normal periphery MOA
CRH(from hypothalamus) - ACTH(from pituitray) - produce cortisol in the glands
Cortisol has a negative feedback loop that decreases CRH
MOA of Addsion’s disease
Low cortisol so increase in CRH and ACTH
- increase in ACTH causes skin pigmentation
MOA of Cuhsing’s disease
There is a tumor in the pituitary or the hypothalamus causing too much ACTH and cortisol
MOA Ectopic ACTH
ACTH elaborated by tumor, causing increased cortisol and decreased ACTH secretion
MOA Ectopic CRH
A tumor causes excess CRH secretion and thus more ACTh and cortisol
MOA of adrenal adenoma or carcinoma
Tumor creates autonomous Cortisol so CRH and ACTH are low and atrophy of adrenal glands
MOA of latrogenic Cushing syndrome
glucocorticosteroids cause an increase in cortisol
Adrenal cortex function - what does it produce
Synthesises:
1. glucocorticosteroids (cortisol)
2. mineralocorticoids
3. androgens
What is produced by each area of the cell? medulla and cortex
medulla - catecholamines
Cortex:
Zone reticularis - gonadocorticoids
Zone fasciculata - glucocorticoids
Zone glomerulosa - mineralocorticoids
How to glucocorticosteroids work?
in the bloodstream, there is a plasma protein carrier molecule from which the steroid hormone detaches and enters the target cell
upon entry to the target cell, the steroid affects processes such as transcriptional regulation (up or down reg), anti-inflammatory and immunomodulatory effects, metabolic effects (making glucose from other sources), stress response, suppression of hypothalamic pituitary adrenal Axis (HPA axis)
what are the functions of glucocorticosteroids?
- Accelerate the breakdown of the proteins and lipids
- help maintain BP
- immune suppression
- support life under stressful events
What is congenital adrenal hyperplasia?
- rare cause in ped patients
- enzymatic defects in the biosynesis of corstiol by the adrenal glands
- causes severe and life-threatening symptoms
- overpordutcion of ACTh causes hyperplasia of the adrenal glans and excessive androgen production
Primary adrenal insufficiency causes
- also known as Addison’s disease
destruction of the adrenal gland through idopathic or autoimmune mechanisms
ex: tuberculosis, trauma, hemorrhage, fungal disease, neoplasia
Secondary adrenal insufficiency causes
- examples is latrogenic cushing syndrome - caused by corticosteroid disease
-hypothalamic-pituaitray dysfucntion
-may also occure due to damage to anterior pituitray or hypothalamus - tumors, infection, radiation, postpartum necrosis, trauma and surgery
What is pro-opiomelanocortin?
it causes increase in MSH which can cause hyperpigmenttation
what is Addisonian crisis and how is it causes?
acute withdrawal of corticosteroids, stree or trauma causes it
life-threathening condition caused by inadequante levels of Glucocorticosteroids and mineralcorticocoids in circulation
Adrenocortical insufficiency diagnostic evaluation
- pateint hx and physcial exam, decrease plasma cortisol levels,
- ACTH test
- MRI or Ct to see size of adrenal glands
Cushing syndrom
hypercortisolism results from chronic exposure to excess circulating levels of glucocorticosteroids
Cushing disease is the most common cause of the syndrome
Cushing Syndrom types?
Spontaneous - 9 times more common in women
latrogenic - chronic glucocorticosteroids
If Acth levels are low/ high?
low - primary
high - secondary
What clinical manifesttaions can we see with cushing’s?
Glucose intolerance, protein catabolism, fat redistribution, skin changes, bone tissues, susuceptibility to infections, hypertension, reproductive system, ocular, CNS,
