An immune-mediated inflammatory disease (IMID) is any of a group of conditions or diseases that lack a definitive etiology

Etiology

Etiology is the study of causation, or origination. The word is derived from the Greek , aitiologia, "giving a reason for" ....

, but which are characterized by common inflammatory pathways leading to inflammation

Inflammation

Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...

, and which may result from, or be triggered by, a dysregulation of the normal immune response. All IMIDs can cause end organ damage

End organ damage

End organ or target organ damage usually refers to damage occurring in major organs fed by the circulatory system which can sustain damage due to uncontrolled hypertension, hypotension, or hypovolemia....

, and are associated with increased morbidity and/or mortality

Death

Death is the permanent termination of the biological functions that sustain a living organism. Phenomena which commonly bring about death include old age, predation, malnutrition, disease, and accidents or trauma resulting in terminal injury....

.

Inflammation is an important and growing area of biomedical research and health care

Health care

Health care is the diagnosis, treatment, and prevention of disease, illness, injury, and other physical and mental impairments in humans. Health care is delivered by practitioners in medicine, chiropractic, dentistry, nursing, pharmacy, allied health, and other care providers...

 because inflammation mediates and is the primary driver of many medical disorders and autoimmune diseases, including ankylosing spondylitis

Ankylosing spondylitis

Ankylosing spondylitis , previously known as Bekhterev's disease, Bekhterev syndrome, and Marie-Strümpell disease is a chronic inflammatory disease of the axial skeleton with variable involvement of peripheral joints and nonarticular structures...

, psoriasis

Psoriasis

Psoriasis is an autoimmune disease that appears on the skin. It occurs when the immune system mistakes the skin cells as a pathogen, and sends out faulty signals that speed up the growth cycle of skin cells. Psoriasis is not contagious. However, psoriasis has been linked to an increased risk of...

, psoriatic arthritis

Psoriatic arthritis

Psoriatic arthritis is a type of inflammatory arthritis that, according to the National Psoriasis Foundation, will develop in up to 30 percent of people who have the chronic skin condition psoriasis...

, Behcet's disease

Behçet's disease

Behçet's disease is a rare immune-mediated systemic vasculitis that often presents with mucous membrane ulceration and ocular involvements...

, arthritis

Arthritis

Arthritis is a form of joint disorder that involves inflammation of one or more joints....

, inflammatory bowel disease

Inflammatory bowel disease

In medicine, inflammatory bowel disease is a group of inflammatory conditions of the colon and small intestine. The major types of IBD are Crohn's disease and ulcerative colitis.-Classification:...

 (IBD), autistic enterocolitis

Autistic enterocolitis

"Autistic enterocolitis" is a controversial term first used by discredited British gastroenterologist Andrew Wakefield to describe a number of common clinical symptoms and signs which he contends are distinctive to autism...

, and allergy

Allergy

An Allergy is a hypersensitivity disorder of the immune system. Allergic reactions occur when a person's immune system reacts to normally harmless substances in the environment. A substance that causes a reaction is called an allergen. These reactions are acquired, predictable, and rapid...

, as well as many cardiovascular, neuromuscular, and infectious disease

Infectious disease

Infectious diseases, also known as communicable diseases, contagious diseases or transmissible diseases comprise clinically evident illness resulting from the infection, presence and growth of pathogenic biological agents in an individual host organism...

s. Some current research even suggests that aging is a consequence, in part, of inflammatory processes.

Characterization

IMID is characterized by immune disregulation

Immune disregulation

Immune dysregulation is an unrestrained or unregulated immune response. An inappropriately robust, or weak immune response. Immune dysfunction....

, and one underlying manifestation of this immune disregulation is the inappropriate activation of inflammatory cytokines, such as IL-12

Interleukin 12

Interleukin 12 is an interleukin that is naturally produced by dendritic cells, macrophages and human B-lymphoblastoid cells in response to antigenic stimulation.-Gene and structure:...

, IL-6

Interleukin 6

Interleukin-6 is a protein that in humans is encoded by the IL6 gene.IL-6 is an interleukin that acts as both a pro-inflammatory and anti-inflammatory cytokine. It is secreted by T cells and macrophages to stimulate immune response, e.g. during infection and after trauma, especially burns or other...

 or TNF alpha, whose actions lead to pathological consequences.