Addisons Disease Causes Symptoms Diagnosis And Treatment

Addison's disease also known as primary adrenal insufficiency or hypoadrenalism is a rare disease caused due to hypofunctioning of the adrenal glands which are located just above the kidneys. The adrenal glands are responsible for the production of hormones namely cortisol and aldosterone. Addison's disease is caused due to lower production of these hormones which could arise due to multiple reasons. These causes may include autoimmune destruction of the adrenal cortex, response to Tuberculosis (TB) infection or amyloidosis.

Cortisol is the body's "Stress" hormone. It is known for its function in the body's "Fight or Flight" response and also, aids in maintaining the rate of metabolism in the body. It has been shown to have anti-inflammatory effects as well. Aldosterone, on the other hand, is known for regulating the salt balance of the body by increasing the resorption of Sodium ions and water into the kidney causing increased secretion of potassium ions. A decrease in the production of these hormones can cause various effects on the body like hypotension, skin, pigmentation, anorexia (loss of appetite), weight loss, fatigue and Depression .

Let us briefly examine the causes of Addison's disease followed by its symptoms, complications, diagnosis and treatment measures.

Causes of Addison's disease
Addison's disease is primarily caused due to deficiency in the hormones produced by the adrenal gland; i.e. glucocorticoid cortisol and mineralocorticoid aldosterone. This condition arises due to production of autoantibodies against the cells on the outer layer of the adrenal gland (adrenal cortex), leading to disruption in production of the key hormones. This is one of the leading causes for the development of this condition. The other causes that may be responsible for the development of this disease include disruption of the adrenal gland caused due to granuloma development (due to TB or histoplasmosis), tumour or hemorrhage. Also, administration of certain drugs like ketoconazole used for blocking synthesis of corticosteroids may be responsible for Addison's disease.

In case of mineralocorticoid deficiency, elevated levels of sodium ions are excreted, while excretion of potassium ions is lowered. Thus, there is excessive water loss leading to dehydration, acidosis, hypotension and finally, circulatory collapse. In case of glucocorticoid deficiency, the body's metabolism of carbohydrates, fats and proteins is disturbed. Absence of cortisol leads to insufficient production of carbohydrates from proteins, causing hypoglycemia and lower levels of glycogen in the liver Impaired neuromuscular function causes tiredness followed by weakened heart muscles and dehydration leading to circulatory failure.

Symptoms of Addison's disease
- Weakness
- Fatigue
These constitute the early signs and symptoms of Addison's disease. This is followed by:
- Hyperpigmentation characterised by diffused tanning of the exposed portions of the body, and to a lower extent unexposed portions like skin folds and scars
- Anorexia (loss of appetite)
- Vomiting
- Diarrhea
The later stages of Addison's disease are characterised
- Weight loss
- Dehydration
- Hypotension

Complications in Addison's disease
In case not diagnosed on time, there could arise a medical emergency condition termed as Addisonian crisis which may lead to coma and can become fatal. This condition may occur if the levels of cortisol suddenly drops too low. When not diagnosed on time or misdiagnosed, the affected patient is suddenly exposed to a highly stressful episode like a surgery, severe injury or infection, etc. Under conditions of such stress, the body ameliorates by producing cortisol. However, due to this condition, the body becomes incapable of coping up with the increased demand for cortisol and hence likelihood for development of Addisonian crisis rises. This condition may also arise if there is excessive loss of salt from the body either due to bleeding or sweating

There could be other possible complications that could arise which are as follows:
- Cardiac arrest which occurs if the heart stops functioning completely
- Stroke if there is an interruption in blood supply to the brain
- Hypovolaemic shock which occurs if there is severe blood and fluid loss
- Hypoxia may occur if the body tissues do not get enough oxygen

Diagnosis of Addison's disease
On approach to a physician post symptom onset, past medical records and history of the patient is first recorded. Symptoms like hyperpigmentation in the skin and gums is generally the first indication for a physician to suspect Addison's disease. Biochemically, higher potassium levels (hyperkalemia) and lower sodium levels (hyponatremia) are positive indicators for Addison's disease.

Serum cortisol level estimation also acts as a fair indicator for this condition. Lower levels of cortisol coupled with increased levels of adrenocorticotropin hormone (ACTH) is the best positive indicator for Addison's disease. Another test called the "synacthen test" aids in assessing functioning of the adrenal glands. This test involves use of a chemical "synacthen" (analog of ACTH) in order to stimulate the adrenal cortex to produce the hormones. Low levels of cortisol even post artificial stimulation is an indicator for Addison's. Other alternatives for diagnosis include X. rays, ultrasound and CT scans of the abdominal region to check for visible signs of damage .

Thyrocare Technologies Limited provides testing options for serum electrolytes (sodium & potassium) using the technology of Ion Selective Electrode (ISE). Testing options are also available for measuring serum levels of cortisol using the Chemiluminescence technology (CLIA) and ACTH using technology of Liquid Chromatography-Mass Spectrometry (LC-MS).

Treatment Options in Addison's disease
The best way to treat Addison's disease is to include regular supplementation with corticosteroids (both cortisol and aldosterone). These medications are required to be taken throughout life, and missing doses can lead to severe complications which can become fatal. At times of Addisonian crisis, hydrocorticosterone must be administered immediately without delay. Patients suffering from this condition are advised Addison's disease. to carry their medical identity cards stating that they have adrenal insufficiency. This ID card should contain information about the type of medication as well as its dosage, in case of an emergency situation.

The treatment recommendations designed varies from one patient to another and is highly individualised. In case of occurrence of any sudden stressful event, these treatment plans may need alterations which should be taken care of. Thus, timely and adequate hormone replacement therapy will aid in better management of this condition to lead a symptom-free life.