HYPERCORTISOLISM

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HYPERCORTISOLISM

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9 Posts

jama
Forum Newbie

Topics: 1
Posts: 3

01/12/08 - 01:28 AM

hi every body

can some help me with questions

i am reading that the best way to differentiate between primary and secondary hypercortisolism is that in primary hyper... the plasma ACTH goes down but in the secondary one it goes up, my question is why does it go up in the secondary doesn't it get brought down and controlled by the negative feedback just like the primary hyercortisolism??

thank you

cirus
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Topics: 108
Posts: 740

01/12/08 - 12:52 PM

In secondry Hypercortisolism, the tumor (most commanly in Lungs), secretes ACTH, not cortisol, so thats why, however the cortisol level is high, the ACTH secretion is not repressed from the tumor, but of course not from the Pitutary.

know it this way:

2ry Hypercortisolism---->

Tumor in lungs ( secretes ACTH) so both ACTH & Cortisol are high, associated with Adrenal Hyperplasia.

Tumor in Adrenal gland (less comman)(Secretes cortisol) So ACTH is very low

hope it helps

jama
Forum Newbie

Topics: 1
Posts: 3

01/13/08 - 01:49 AM

it does help thanks cirus

Ig F
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02/27/08 - 06:14 PM

easy and simple explanation.....good work cirus......

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taipei817
Forum Junior

Topics: 2
Posts: 78

03/03/08 - 10:20 AM

a little confused on this topic in terms of ACTH molecules or ACTH-like molecules. In squamous cell carcinoma of the lung, usually it secretes a PTH-like molecule and the patient would be hypercalcemic with low PTH. What about the small cell carcinoma? Do they secrete ACTH or ACTH-like or both or who cares?

pr20
Forum Senior
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Topics: 20
Posts: 168

03/03/08 - 10:52 AM

Small cell carcinoma of lung and Medullary carcinoma of thyroid secrete ACTH causing ectopic cushing's syndrome(hypercortisolism).Plasma ACTH levels will be markedly increased.Plasma levels of ACTH are even greater than those seen with pituitary cushing's.

keepgoing
Forum Guru

Topics: 63
Posts: 1,676

03/05/08 - 04:48 AM

secondary hypercortisolism also from pit.tumor secreating large amount of ACTH which stimulates fasiculta and retucularis layers of adrenal gland and secreting large amount of cortisol that cant supress ACTH(exceeds valueb/c continous secreation by tumor) by negatiive feedback so we see.increased ACTH and increased cortisol.isn't it?

new_n_lost
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03/05/08 - 06:11 AM

My way of looking at it is like this that any cause of Secondary Hyper cortisolism is due to the fact that extra ACTH is being produced which is not regulated by the Pituitary. Whether the tumor is in Pituitary or Lungs the ACTH will be increased. While in the Adrenal (primary) case it will be decreased as the production of cortisol is due to a tumor in adrenal gland.

And in case of Secondary Hypercortisolism the Pituitary has the highest number of incidence 60% and then comes Neuroendocrine tumors eg Oat cell ca 15%

But remember the overall and most common cause of Cushing sydrome is exogenous intake of steroids.

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keepgoing
Forum Guru

Topics: 63
Posts: 1,676

03/05/08 - 07:29 AM

new_n_lost wrote:
My way of looking at it is like this that any cause of Secondary Hyper cortisolism is due to the fact that extra ACTH is being produced which is not regulated by the Pituitary. Whether the tumor is in Pituitary or Lungs the ACTH will be increased. While in the Adrenal (primary) case it will be decreased as the production of cortisol is due to a tumor in adrenal gland.

And in case of Secondary Hypercortisolism the Pituitary has the highest number of incidence 60% and then comes Neuroendocrine tumors eg Oat cell ca 15%

But remember the overall and most common cause of Cushing sydrome is exogenous intake of steroids.

i agree.

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