What is the term for the condition when the body's immune system attacks its own tissues?

The condition when the body's immune system attacks its own tissues is referred to as an autoimmune disease. In autoimmune disorders, the immune system fails to distinguish between self and non-self, leading to the attack of the body's own cells, tissues, or organs. This misdirected immune response can result in inflammation and damage to various body parts, potentially causing a wide range of health issues, depending on the specific tissues affected.

For instance, conditions like rheumatoid arthritis, lupus, and type 1 diabetes fall under this category, highlighting the diverse ways the immune system can malfunction. The specificity of this term is critical since it encapsulates the fundamental characteristic of the condition—an attack on self rather than an external invader.

Other terms in the options describe different processes. An allergy involves an exaggerated response of the immune system to usually harmless substances, while immunodeficiency refers to a weakened state of the immune system that makes an individual susceptible to infections. Infection, on the other hand, pertains to the invasion of the body by pathogens such as bacteria or viruses, which is distinct from the self-targeting behavior seen in autoimmune diseases.