There are two main types of Addison’s disease, also known as primary adrenal insufficiency:
- Autoimmune Addison’s Disease: This is the most common form of Addison’s disease, accounting for approximately 70-80% of cases. In autoimmune Addison’s disease, the body’s immune system mistakenly attacks and destroys the adrenal cortex, which is the outer layer of the adrenal glands. The destruction of the adrenal cortex leads to a deficiency in cortisol and aldosterone production. Autoimmune Addison’s disease is often associated with other autoimmune conditions, such as autoimmune thyroid disease or type 1 diabetes.
- Non-Autoimmune Addison’s Disease: This type includes cases of Addison’s disease that are not caused by autoimmune destruction of the adrenal cortex. Non-autoimmune Addison’s disease can be further classified into various subtypes based on the underlying cause. Some examples include:a. Infections: Certain infections, such as tuberculosis, fungal infections (e.g., histoplasmosis, coccidioidomycosis), or HIV/AIDS, can affect the adrenal glands and result in adrenal insufficiency.b. Adrenal Gland Damage: Trauma, bleeding into the adrenal glands (adrenal hemorrhage), tumors (e.g., metastatic cancer), or surgical removal of the adrenal glands can lead to adrenal insufficiency.c. Genetic Disorders: Rare genetic disorders, such as congenital adrenal hyperplasia, adrenoleukodystrophy, or familial glucocorticoid deficiency, can cause adrenal insufficiency.d. Medications or Toxins: Prolonged use of medications that suppress adrenal function, such as corticosteroids, can result in adrenal insufficiency when the medication is withdrawn or reduced. Certain toxins, such as those found in some fungal infections or certain chemicals, can also damage the adrenal glands.e. Other Causes: Less commonly, other factors such as amyloidosis, metastatic cancer, or sarcoidosis can affect the adrenal glands and lead to adrenal insufficiency.
It’s important to note that autoimmune Addison’s disease is the most prevalent form, while non-autoimmune causes are less frequent. However, the specific type and underlying cause of Addison’s disease can vary from person to person. Proper evaluation and diagnosis by a healthcare professional are necessary to determine the specific type and appropriate management for each individual case.