[Biology Class Notes] on Adrenal Insufficiency Pdf

The Adrenal glands are the producer of hormones, which sits atop of your kidneys. The outer part of the gland is called the Adrenal cortex, which produces the hormones Cortisol and Aldosterone. When the cortex is not producing the normal hormone level it is known as Adrenal Insufficiency. According to the Mayo clinic, Adrenal Insufficiency is a disorder that is caused when Adrenal glands produce too little Cortisol and often Aldosterone. This condition affects both men and women and can happen at any age. When your adrenal glands are not functioning properly your entire body could be affected. As cortisol plays a role in converting your food into energy keeping your immune system inflammatory response in check and helps your body respond to stress. Aldosterone helps to keep your blood pressure normal. Symptoms of adrenal insufficiency include extreme fatigue, nausea or vomiting, depression, and darling of your skin among others. The failure of your adrenal glands to produce a sufficient amount of hormones is most commonly the result of an autoimmune disease, but also can be caused by tuberculosis, the spread of cancer to the adrenal glands, and infection of the adrenal glands among others. Treatments are available that can help correct or replace hormones in your system, so it’s important to speak to your doctors if you have any of these symptoms. The term adrenal insufficiency refers to as a syndrome, while by the specific diseases that cause a syndrome are differentiated as the primary adrenal insufficiency referring to the adrenal glands as the source of the pathology or the secondary adrenal insufficiency referring to the hypothermic or the pituitary as the source of the pathology.  

PRIMARY ADRENAL INSUFFICIENCY

This is also known as Addison’s Disease is a rare endocrine disorder that happens when the adrenal gland isn’t able to produce enough of the hormones that the body needs particularly aldosterone and cortisol. The reason it is called as primary is that the underlying problems localized to the adrenal glands itself. Rather than a problem of a hormone that acts on the adrenal gland or elsewhere in the body. We need to first understand the adrenal gland and its functions. The inner part of the adrenal gland is called the Medulla, this Medulla secretes the catecholamine. The outer part is the Cortex, this secretes aldosterone, cortisol, and sex steroids. Let us first understand the functions of these hormones

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ALDOSTERONE

1. Aldosterone increases sodium and water reabsorption in the kidneys.

2. It also causes excretion of potassium in the kidneys. 

3. It also helps to maintain normal blood pressure   

 CORTISOL

1. Cortisol stimulates gluconeogenesis in the liver and helps to maintain normal glucose concentration of the blood

2. It also stimulates lipolysis throughout the body

3. It depresses the immune response

4. It also helps to decrease the inflammation

SEX STEROIDS

They are mainly associated with the development of secondary sexual characteristics.

The deficiency in the secretion of all these hormones which causes to develop Addison’s disease If we see the etiology of Addison’s disease, if we see the causes for this it would include.

CAUSES

1. AUTOIMMUNE ADRENALITIS 

In this case, the bodies own B cells and the D cells attack the adrenal glands and damage it.

2. INFECTIONS

This is caused by organisms like mycobacterium, tuberculosis, and also fungal infections like Histoplasmosis. 

3. ADRENAL INFECTION

This happens in cases of systemic lupus erythematosus and antiphospholipid antibody syndrome.

4. DRUGS

Drugs like mitotic and ketoconazole, when taken in excess, can damage the adrenal glands.

5. METASTASIS

Metastasis from the organs like lungs and the stomach can also damage the adrenal glands.

6. TRAUMA

Trauma to the abdomen either blunt or sharp will also cause damage to the adrenal gland.

7. ADRENAL HEMORRHAGE

This happens in the case of Waterhouse Fredrickson syndrome and anticoagulation therapy can also cause adrenal insufficiency.

8. STORAGE DISORDERS

Storage disorders like amyloidosis and hemochromatosis also affect the adrenal gland.

9. SURGERY

The surgical removal of the adrenal gland which is also known as the bilateral adrenalectomy causes Addison’s disease. 

 

CLINICAL FEATURES

1. CORTISOL DEFICIENCY 

The clinical features due to cortisol deficiency usually manifest as fatigue, anorexia, weight loss, muscle weakness, abdominal pain, diarrhea, and hypoglycemia which manifests as sweating and headache. Another symptom is the hyperpigmentation which occurs in areas like hands and the buccal mucosa. It is important to understand why the hyperpigmentation occurs, the pituitary secretes Melanocyte-stimulating Hormone (MSH) and Adrenocorticotropic Hormone (ACTH). The ACTH acts on the adrenal and causes an increase in the secretion of cortisol and rest is converted into alpha MSH. In the case of Addison’s disease, the cortisol secretion is decreased through a feedback machinist, there is a reflex that causes the increase of the secretion of MSH and ACTH. The increase in MSH causes hyperpigmentation.

2. ALDOSTERONE DEFICIENCY

Since aldosterone is important to maintain normal blood pressure, it’s deficiency manifests as low blood pressure. These patients also have orthostatic hypotension, as the blood pressure further falls when they rise up after sitting. In this, the patents have a craving for salty food.  

3. SEX STEROID DEFICIENCY

This manifests as a loss of libido in both sexes and menstrual irregularities in females. 

DIAGNOSIS   

1. Blood glucose measurement shows a low plasma blood group.

2. Plasma cortisol between 8 am to 9 am shows a value of fewer than 3 mg/DL.

3. ACTH stimulation test is important to diagnose adhesions disease. 

4. Plasma ACTH levels are usually elevated 100

5. Autoimmune adrenalitis organ-specific antibodies can be deducted like adrenal cortex antibodies 21 hydroxylase antibodies.

SECONDARY ADRENAL INSUFFICIENCY

This is also called acute secondary Adrenal insufficiency, meaning the pathology has been present for days or weeks or chronic, meaning the pathology has been present for weeks or months. The pathology of the level of the hypothalamus or the pituitary. With the pathology at the level of the pituitary such that the  (Adrenocorticotropic hormone) production is deficient since cortisol is entirely dependent upon ACTH, even though are healthy and capable there is no cortisol synthesis. Thus the pathognomonic laboratory characteristics include low basal cortisol, inappropriately low ACTH. Some patients might be hyponatremic, however, since aldosterone regulations are not dependent on ACTH potassium homeostasis should be unimpaired. The clinical manifestation in secondary Adrenal insufficiency depends upon the degree of stress the patience is facing and the relative deficiency of cortisol in that degree of stress. Thus the manifestation can range from almost no abnormalities to mild, moderate, or severe signs of fatigue, orthostasis, hypotension, in the situations of stress. Since the adrenal glands in acute secondary Adrenal insufficiency are intact, in response to exogenous cosyntropin they are expected to display a robust cortisol secretion. However, if the deficiency of ACTH should continue for weeks or months over time it will lead to decreased secretion of adrenal androgens and cortisol.

CAUSES  

1. Secondary Adrenal insufficiency can be caused by an insult or injury to the hypothalamus of the pituitary which can include 

2. The most common cause is the medication, which includes

3. A condition that damages your pituitary gland will eventually result in reduced production of ACTH, this then further leading to the cortex not receiving sufficient hormones to stimulate it.

4. A sudden miss of corticosteroid drugs that are used to treat conditions like Asthma or Arthritis will also lead to Cortex malfunction and which is also known as Secondary Adrenal Insufficiency

5. This state would result in a reduction in the secretion of Cortisol and Aldosterone, even though there is no issue in the adrenal cortex.

TREATMENT

In this case, the patients require glucocorticoid replacement such as prednisone or hydrocortisone.