Content Reviewers:Rishi Desai, MD, MPH
Autoimmune means that the body’s immune system begins to attack its own tissues, and polyglandular means that multiple hormone-producing organs are affected.
Normally, your body should only react to things that are foreign or not-self.
For T-cells, this process takes place in the thymus, where a gene called AIRE, or autoimmune regulator, is expressed by thymic medullary epithelial cells.
In APS type 1, there’s a genetic mutation in AIRE that’s usually inherited in an autosomal recessive fashion.
This means that the thymic medullary epithelial cells lose the ability to display the body’s different self-proteins.
Regulatory T-cells are no longer produced normally either, so the body loses a second mechanism for destroying autoimmune cells.
This allows for the production of antibodies and lymphocytes that target normal tissues of the body. It is still unclear why, but certain glandular tissues, including the adrenal glands and parathyroid glands, are particularly targeted.
There are multiple characteristic signs and symptoms of APS type 1.
One of them is polyendocrine malfunction resulting in hypoparathyroidism, characterized by low calcium and elevated phosphorus in the blood that can cause muscle cramping and seizures, and primary adrenal insufficiency, also called Addison’s disease, which can reduce cortisol and aldosterone levels.