Which condition is associated with Type III hypersensitivity?

Type III hypersensitivity, also known as immune complex-mediated hypersensitivity, occurs when antigen-antibody complexes form and deposit in various tissues. This deposition triggers an inflammatory response, primarily through the activation of complement and recruitment of leukocytes, leading to tissue damage.

Systemic lupus erythematosus (SLE) is associated with Type III hypersensitivity because it is a systemic autoimmune disease characterized by the production of autoantibodies that bind to nuclear antigens, forming immune complexes. These immune complexes can deposit in tissues such as the kidneys, skin, and joints, causing inflammation and damage, which is a hallmark of SLE.

In contrast, Goodpasture syndrome involves Type II hypersensitivity, where antibodies target specific tissue components (such as collagen in the basement membranes of the lungs and kidneys) and lead to a direct cytotoxic effect. Autoimmune hemolytic anemia is also a Type II hypersensitivity condition, characterized by antibodies directed against red blood cells, resulting in their destruction. Anaphylaxis, on the other hand, is a classic example of Type I hypersensitivity, driven by IgE-mediated release of histamine and other mediators from mast cells.

Understanding the underlying mechanisms of each condition helps clarify why systemic lupus erythemat