Cortisol

[SarahB79]

I recently took a cortisol test to check for pituitary and adrenal gland tumors (with a pill taken at 11 PM the night prior).  I think the test would come back with a high level to indicate the precence of a tumor.  What would a really low level indicate?  

[Lama Chahine, MD]

Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with your doctor.

It sounds like you'd like more information regarding cortisol levels, and specifically what a low cortisol level implies.

Normally, a structure in the brain stimulates the pituitary gland in the brain to secrete as substance called ACTH. ACTH then stimulates the adrenals (a gland in the kidneys), to secrete cortisol and other hormones.

A low cortisol level is sometimes medically referred to as "adrenal insufficiency". It can be what is called primary, meaning the adrenal gland itself (a gland above the kidney that normally secretes cortisol) is not working properly. It can also be secondary, meaning that the problem is not in the adrenal gland but rather in the glands that stimulate the adrenal i.e the pituitary gland (located in the brain) or the hypothalamus (also located in the brain).

A low cortisol level (assuming that is confirmed with further testing and the testing is done appropriately and at the right time of day) implies that either (1) the hypothalamus is not functioning OR (2) the pituitary gland is not functioning or (3) the adrenal gland is not functioning.

In some uncommon cases, a tumor in the pituitary gland can develop that secretes ACTH. Since ACTH stimulates the adrenal gland to secrete cortisol, the tumor overproduces ACTH, causing the adrenal gland to overproduce cortisol, and cortisol levels will be high.

On the other hand, if there is another type of tumor in the pituitary gland which is NOT secreting ACTH, the entire gland may not function properly. In such cases, the pituitary is unable to release ACTH, and is therefore unable to stimulate the adrenal gland to secrete cortisol. In such cases, cortisol levels will be low.

The link between all the areas that are involved in the secretion of cortisol, called the hypothalamic-pituitary-adrenal axis, is very complex. Sometimes several tests are required to confirm and abnormality and determine its cause. It is also very important that the blood test findings are correlated with clinical information: what the patient is experiencing and the physical examination of the patient.

Thank you for this opportunity to answer your questions, I hope you find the information I have provided useful, good luck.

[SarahB79]

Wow!  Thank you for such detailed information.  I was at work when I posted yesterday and didn't have my test results to provide more information.. nor did I mention any of my symptoms.  

My test was done at 8 AM and from my paper work it looks like the 7-9 AM test reference range would be between 4.0-22 mcg/dl.  My result was 1.9.

I am newly diagnosed diabetic.  Recently have experienced weight gain of about 35 lbs.  And have been experiencing stress, stomach aches, and mild depression.  

One thing that has happened twice in the last few weeks, when sudden stress comes on the normal stress symptoms appear, but then I get very bad pain in both of my kidneys.  It happened 2 days ago when under sudden stress and it now continues to be a dull ache.  

Also, my gyno requested and ACTH test about a year and a half ago along with a few other hormone related tests due to the fact I was still secreting minor amounts of breast milk after 5 years of non-nursing.  They also started me on birth control for ovulation pain, endometriosis and cysts.  The secretion stopped, so I failed to follow through with the test.  Now, I am thinking that was probably dumb...


Thank you again for your help.