Acth Stimulation Test For Cortisol Blood

The ACTH stimulation test is used to assess the functioning of adrenal glands and their response to adrenocorticotropic hormone (ACTH). This test helps in diagnosing congenital adrenal hyperplasia and to evaluate primary or secondary adrenal insufficiency.

What is the importance of ACTH?

Adrenocorticotropic hormone (ACTH) stimulates the adrenal gland and it produces two hormones: adrenaline and cortisol.

• Adrenaline is also known as epinephrine. It is transported through the bloodstream and affects the autonomous nervous system, which plays a role in controlling heart rate, secretion of sweat and saliva, dilation of pupils, etc.
• Cortisol is the main hormone which is involved in fight-or-flight and stress response and regular blood glucose. If you experience sudden emotions like a threat, the adrenocorticotropic hormone is released in your brain which stimulates the adrenal gland to produce cortisol and adrenaline. When high levels of cortisol are released, it boosts energy and strength. In most cases, the cortisol levels are observed to be highest in the morning and lowest around midnight.

These hormones support the immune system and help in dealing with stress.

Why this test is performed?

This test may be recommended to you if you experience certain conditions like high blood pressure, high blood sugar, bruises on the skin, skin that is thin, pink or purple color streaks on the thighs, stomach or hip region, acne, osteoporosis (a condition in which, bones become weak and brittle), muscle weakness, irregular menstrual periods or hair growth on face and chest in women, weight loss, low blood pressure, muscle aches, joint pains, stomach ache, extreme tiredness, nausea and vomiting, diarrhea, dark patches on the skin, decreased armpit hair and pubic hair and also decreased sexual desire in case of women, etc,

This test may also be preferred if you are suspected to have ACTH deficiency, adrenal gland related problems, like Addison disease or pituitary insufficiency or disorder of steroid biosynthesis, Congenital adrenal hyperplasia, etc. This test is also used to check if pituitary or adrenal glands have recovered the damage caused due to long-term use of glucocorticoid medicines.

Precautions:

Certain medications as glucocorticoids (prednisolone, budesonide, cortisone, betamethasone, etc) may interfere with your test results. Hence inform your doctor or technician about all your current medications and medical conditions prior to the test.

The normal reference range may vary depending on gender, age, health history, etc.

There will be an increase in cortisol levels after stimulation by ACTH. Post-stimulation the cortisol levels in the blood should be greater than 20 mcg/dl.

If your test results show abnormal results, it may be due to an acute adrenal crisis (insufficient cortisol production), hypopituitarism (low pituitary function), Addison disease (a condition in which adrenal glands do not produce sufficient cortisol), pituitary tumors, etc.