Autoinflammatory diseases

Not to be confused with Autoimmune disease.

Autoinflammatory diseases (AIDs) are a group of rare disorders caused by dysfunction of the innate immune system. They are characterized by periodic or chronic systemic inflammation, usually without the involvement of adaptive immunity.

Autoinflammatory diseases are a separate class from autoimmune diseases. Both are characterized by an immune system malfunction that may cause similar symptoms, such as rash, swelling, or fatigue, but the cardinal cause or mechanism of the disease is different. A key difference is a malfunction of the innate immune system in AIDs, while in autoimmune diseases there is a malfunction of the adaptive immune system.

The boundaries between autoinflammation (overactivity of the innate immunity), autoimmunity (overactivity of the adaptive immunity), and immunodeficiency (decreased activity of the innate or adaptive immunity) are often fluid. Clinical phenotypes associated with these processes are driven by the cell type most affected by a particular mutation or signal. Excessive activation of neutrophils, monocytes/macrophages, and dendritic cells leads to autoinflammatory symptoms, while T cell and B cell dysfunction leads to autoimmunity. Failure of innate and/or adaptive immune cells to appropriately activate, recognize, and clear infectious agents causes immunodeficiency and vulnerability to infection.