Cortisol Hormone, Hydrocortisone (AM and PM) and Cushing’s syndrome
Cortisol Hormone
What sample is needed for the estimation of Cortisol Hormone?
- It is performed on serum (3-5 mL of clotted blood to make serum).
 - Also, it can be done on plasma.
 - Collect the blood at 8 a.m.
 - Then, collect blood at 4 p.m.
- The 4 pm value is one-third to two-thirds of the 8 am value.
 
 - The sample can be stored at 4°C for up to 2 days.
 - For a longer period, freeze the sample.
 - Urine sample: This is a 24-hour urine sample. Add 20 mL of acetic acid (30%) to the container.
- Or preserve with 1 gram of boric acid.
 
 
What are the Indications for the Cortisol Hormone?
- This will measure the serum cortisol level.
 - Cortisol level is estimated to rule out hypo- or hyperfunction of the adrenal gland.
 
What are the precautions for Cortisol Hormone?
- There is increased value during pregnancy.
 - Emotional and physical stress can increase value.
 - Drugs like amphetamine, estrogen, cortisone, oral contraceptives, and spironolactone can increase value.
 - Drugs like androgens, betamethasone, exogenous steroids, lithium, danazol, Dilantin, and methyldopa can decrease the value.
 
How will you discuss the pathophysiology of the Cortisol Hormone?
- This is a major adrenal gland glucocorticoid synthesized in the zona fasciculata of the adrenal cortex, and this will control the metabolism of:
- Glucose (Carbohydrate).
 - Lipids (fats).
 - Proteins.
 
 - The zona fasciculata is the middle zone, and it produces 17-hydroxycortisone, also known as cortisol or hydrocortisone.
 - The inner zone is the zona reticularis, which produces androgens or estrogen.
 
- The adrenal cortex produces a variety of steroid hormones.
 
- This hormone plays a crucial role in the body’s metabolism.
- Cortisone and its oxidation products are inactivated in the liver by two separate reduction processes (hydrogenation) into tetrahydro-derivatives.
 - This will conjugate with glucuronic acid in the liver and then be excreted in the urine.
 
 - Cortisol is a steroid.
- Because of its tight binding with Cortisol-Binding Globulin, cortisol is metabolized slowly.
 
 
What are the types of Cortisol present in the body?
- One of the references gives the following figures.
- 75% is bound to alpha-1-globulins called transcortin.
 - 15% is bound to albumin.
 - 10% is unbound and is in free form.
 - The bound form is not physiologically active.
 
 
- The kidney, liver, and thyroid diseases affect the secretion and metabolism of cortisol (adrenal gland steroids).
 - Other factors that affect cortisol levels include age, stress, nutrition, estrogen therapy, and certain medications.
 - The glucocorticoid hormone is secreted at a rate of 10 to 30 mg/24 hours, influencing carbohydrate metabolism.
- Adrenal Cortisol, roughly 25 mg, is produced in 24 hours, while plasma concentration is 5 to 25 µg/dL.
 
 - Cortisol plays a role in the metabolism of carbohydrates, proteins, and fats.
 - Cortisol breaks down the proteins.
- There is an amino acid formation.
 - Amino acids are converted into glucose.
 - Cortisol is an insulin antagonist.
 - Cortisol is a glucocorticoid secreted by the adrenal cortex in response to ACTH stimulation.
 
 
What is the metabolism of the Cortisol hormone in the body?
- The cholesterol gives rise to cortisol in the adrenal zona fasciculata and reticularis of the adrenal cortex.
 - After entering the bloodstream, it binds with corticosteroid-binding globulin.
 - Cortisol will be metabolized and conjugated in the liver.
- >95% cortisol metabolites conjugate with glucuronic acid and are excreted in urine as such.
 - <2% unmetabolized cortisol is excreted in the urine.
 
 
How is the Cortisol hormone transported in the body?
- Another reference gave these figures:
 -  Freeform.
- Approximately 5% is free.
 
 - Bound form.
- 85% binds the corticosteroid-binding α-globulin (transcortin).
 - 10% bound to albumin.
 
 
What is the cortisol hormone control mechanism?
- The hypothalamus controls ACTH, as well as Corticotropin-releasing hormone (CRH).
 - In the case of increased ACTH, cortisol is excreted within a few minutes.
 - Decreased ACTH level leads to the atrophy of the zona fasciculata (and zone reticularis).
 - Exogenous glucocorticoids lead to suppression of ACTH and adrenocortical atrophy.
 
- Corticotropin-releasing hormone ( CRH ), made in the hypothalamus, stimulates the anterior pituitary gland to produce ACTH, which stimulates the adrenal cortex to produce cortisol.
 - Cortisol in blood exists in the following forms:
- Cortisol-free.
 - Cortisol in total.
 - <2% cortisol is excreted unchanged in the urine.
 
 
What are the functions of the Cortisol hormone?
- Cortisol controls the glucose level in the blood:
- By suppressing the secretion of insulin.
 - It inhibits the uptake of glucose by the peripheral tissues.
 - It promotes hepatic glucose synthesis.
 
 - Cortisol increases glucose levels by increasing gluconeogenesis in the liver (from the glucose store).
 - Cortisol regulates the metabolism of carbohydrates, fats, and proteins.
 - It has anti-inflammatory properties:
- By suppressing the cytokines.
 - It decreases the eosinophils (inhibitory effect on eosinophils).
 - It depresses the T-lymphocytes.
 
 - In case of overproduction of cortisol hormones:
- It causes poor wound healing.
 - There may be bruising.
 - There is immunosuppression during infection.
 
 - Cortisol regulates water-electrolyte balance:
- Water migrates into extracellular fluids through renal excretion.
 - Excessive levels of Cortisol cause an accumulation of water in the face and other body areas.
 
 
- Cortisol plays a role in the immune system.
 - It is influenced by factors such as heat, cold, infection, trauma, exercise, debilitating diseases, and obesity.
 
What are the conditions under which Cortisol level variations occur?
- There are diurnal variations in cortisol secretion, with higher levels in the morning (6 to 8 AM) and the lowest levels between 4 to 6 PM. The level also starts decreasing and reaches its lowest levels at midnight. So, a random sample is not helpful.
- The highest level is between 6 to 8 AM.
 - The lowest level is between 4 to 6 PM. (Gradually false during the day, lower between 4 to 6 pm.)
 - The lowest level is at midnight.
 
 
How will you describe the cortisol variation according to time?
| Cortisol pattern | Cortisol level | Mechanism | 
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| Significance of the cortisol level | 
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- Cushing’s syndrome typically has an elevated morning level.
- Cushing’s syndrome does not show diurnal change.
 - There is no decline throughout the day.
 
 - Addison’s disease has the lowest level.
- The variation is lost under stress.
 
 
What is the mechanism of Cortisol excretion?
- Mostly >1% of the total cortisol is synthesized daily and is excreted as such in the urine.
 - Approximately 30% to 50% appears as glucuronide conjugates, specifically as tetrahydro-derivates of cortisol and cortisone.
 - All these compounds contain the dihydroxyacetone group in the side chain, known as 17-hydroxycorticosteroid (17-OHCS).
 - There is a higher concentration of these compounds in the urine.
 - Chemical estimation of urinary 17-OHCS or 17-ketogenic steroids does not accurately estimate plasma cortisol concentration or output because they may form other steroids with similar structures.
 
What is the Normal Total cortisol hormone?
Source 2
- Serum AM (8 am) = 5 to 23  µg/dL
- Serum PM (4 pm) = 3 to 13 µg/dL
 
 - Urine (free cortisol) = 20 to 90 µg /24 hours
 - Children = 1 to 16 years old.
- 8 AM = 15 to 25 µg/dL
 - 4 PM = 5 to 10 µg/dL
 
 - Newborn = 1 to 24  µg/dL
- Maternal at birth = 51.2 to 57.4 µg/dL
 
 - The blood sample was usually taken at 8 am and 4 pm; the 4 pm level is one-third to two-thirds lower than the 8 am level.
 - Urine 24 hours
- Adult/old people = <100 µg/dL/24 hours (<276 nmol/day).
 - Adolescent = 5 to 55 µg/dL/24 hours
 - Child = 2 to 27 µg/dL/24 hours
 
 
Source 1
What are the values of total Cortisol (free and bound by RIA)?
| Age | µg/dL | nmol/L | 
| Cord blood | 5 to 17 | 138 to 469 | 
| Infants 1 to 7 days | 2 to 11 | 53 to 304 | 
| Children 1 to 16 years | 3 to 21 | 83 to 580 | 
| Adult | ||
| 0080 AM | 5 to 23 | 138 to 635 | 
| 1600 PM | 3 to 16 | 83 to 441 | 
| 2000 PM | <50% of 0800 AM value | <50% of 0800 AM value | 
| Maternal at birth | 54.3 ± 3.1 | |
| Cortisol Free 24 hours of urine | ||
| Child | ||
| 1 to 10 years | 2 to 27/day | 6 to 74 | 
| 11 to 20 years | 5 to 55 | 14 to 152 | 
| Adult | 20 to 90 | 52 to 248 | 
| Serum (free cortisol) | ||
| Adult | ||
| 0800 AM | 0.6 to 1.6 | 1.7 to 4.4 | 
| 1600 PM | 0.2 to 0.9 | 0.6 to 2.5 | 
- For conversion of µg/dL into SI unit x 27.6 = nmol/L
 
Source 4
Cortisol Hormone Level
- 0800 AM =5 to 23 µg/dL (138 to 635 nmol/L).
 - 4.00 PM = 3 to 16 µg/dL (83 to 441 nmol/L).
 - Midnight = <50% of 0800 AM level.
 - Newborn = 2 to 11 µg/dL (55 to 304 nmol/L).
 - Maternal at birth = 52.1 to 57.4 µg/dL   (1413 to 1584 nmol/L).
- After the first week of life, cortisol levels reach adult levels.
 
 
What are the conditions where there is an increased level of cortisol?
- Cushing syndrome (Pituitary disease)
 - Adrenal adenoma and carcinoma.
 - Pregnancy leads to a raised level.
 - Physical and emotional stress can increase levels.
 - Ectopic ACTH-producing tumors.
 - Hyperthyroidism.
 - Stress.
 - Major depression.
 - Severe anxiety.
 - Obesity. All steroid hormones are elevated in obese individuals, which may be due to increased deposition or synthesis in fat tissue.
 
- An extremely high level is seen in Ectopic ACTH syndrome.
 
What are the conditions where there is a decreased level of cortisol?
- Addison’s disease.
 - congenital adrenal hyperplasia ( adrenogenital syndrome )
 - Hypopituitarism.
 - Hypothyroidism.
 
Cushing’s syndrome:
What is the definition of Cushing’s syndrome?
- Cushing’s syndrome is characterized by an increase in serum cortisol production.
 - Basically, this condition is due to excessive body levels of glucocorticoids like cortisol, and this may be:
- Primary where there is overproduction due to the adrenal cortex.
 - The secondary is due to therapeutic therapy.
 
 
What are the causes of Cushing’s syndrome?
- Approximately 70% of cases are attributed to the overproduction of cortisol by the adrenal cortex, resulting from pituitary hypersecretion of ACTH, which leads to bilateral adrenal cortex hyperplasia.
 - 10% of the cases are due to an adrenal cortex gland adenoma.
 - 10% of the cases are due to adrenal cortex carcinoma.
 - Around 28% to 38% of the cases are ectopic production of ACTH, like lung small cell carcinoma.
 - Few cases are caused by thymus carcinoid, pancreatic islet cell tumors, pheochromocytoma, and various adenocarcinomas.
 
What is the clinical presentation of Cushing’s syndrome?
- Cushing’s syndrome is more common in females, 4 times more than in males.
 - There is truncal obesity.
 - Neuropsychiatric symptoms.
 - There is hypertension.
 - There is an intolerance of carbohydrates.
 - There is hyperglycemia and decreased glucose tolerance.
 - There are polyuria and polyphagia.
 - There are hirsutism and acne.
 - There are proximal myopathy and weakness.
 - The patients are prone to easy bruising.
 - There are sexual dysfunction and menstrual problems.
 
How will you diagnose Cushing’s syndrome?
- There is hypokalemic metabolic alkalosis.
 - There is an increase in urinary-free cortisol.
- Single increased serum cortisol level.
 - Or advise 24-hour urinary 17-OHCS.
 
 - Measure urine 17-ketosteroids for the diagnosis of Cushing’s syndrome.
- It has increased from 50% to 55% of Cushing’s syndrome patients.
 
 - Diurnal variation is absent in 90% of the cases.
- Take two blood samples, one at 8 A.M. and one at 8 P.M.
 - There will be no diurnal variation.
 
 - There is a lake of normal suppression by dexamethasone.
- Low-dose dexamethasone suppression test, where the cortisol level remains elevated.
 
 - A high level of cortisol indicates Cushing’s syndrome.
 - A low level of cortisol indicates Addison’s disease.
 
How will you differentiate Adrenal diseases?
| Disease | ACTH value | Cortisol value | 
|---|---|---|
| Cushing’s syndrome causes | ||
| Adrenal adenoma | Low | Raised | 
| Adrenal cancer | low | Raised | 
| ACTH-producing Pituitary tumor | Raised | Raised | 
| Ectopic ACTH (Lung cancer) | Raised | Raised | 
| Addison’s disease causes | ||
| Adrenal gland failure (Infarction, Haemorrhage) | Raised | Low | 
| Congenital adrenal hyperplasia | Raised | Low | 
| Hypopituitarism | Low | Low | 
What is the value of urinary cortisol per/day in various diseases?
| Disease | µg free cortisol/day | 
| Normal | <100 | 
| Adrenal tumors | >120 | 
| Ectopic ACTH syndrome | >120 | 
| Cushing’s syndrome | >120 | 
What is the function of the cortisol hormone?
- It regulates the body’s response to stress.
 - Cortisol stimulates the release of glucose from the liver in response to stress.
 
What happens when the cortisol level is high?
- High cortisol hormone level leads to:
- Weight gain.
 - Headache.
 - Irritability etc.
 - It suppresses inflammation.
 - It regulates blood pressure.
 - It regulates blood glucose levels.
 
 
What is the effect of the cortisol hormone on behavior?
- Excessive levels of cortisol, like in Cushing’s syndrome, lead to depression.
 
Questions and answers:
Question 1:  What is the precursor of the cortisol?
Question 2:  When is the cortisol level high during the day?
Question 3:  What is the cause of Cushing's syndrome?
                        











