complementrelated

Complement-related disorders refer to a group of conditions caused by dysfunctions in the complement system, a crucial part of the immune response in humans. The complement system consists of a series of proteins found in the blood that enhance the ability to clear microbes and damaged cells from an organism, promote inflammation, and attack the pathogen’s cell membrane. Dysregulation in this system can lead to autoimmune diseases, increased susceptibility to infections, or inflammatory disorders.

One well-known complement-related disorder is **paroxysmal nocturnal hemoglobinuria (PNH)**, a rare, chronic blood disorder characterized by the destruction of red blood cells, leading to anemia, fatigue, and other complications. PNH arises from mutations in the *PIG-A* gene, impairing the attachment of proteins to red blood cells, making them vulnerable to complement-mediated lysis. Treatment often involves complement inhibitors like eculizumab or ravulizumab to prevent excessive complement activation.

Another significant condition is **atypical hemolytic uremic syndrome (aHUS)**, a form of thrombotic microangiopathy caused by uncontrolled complement activation, particularly through mutations in complement regulatory genes such as *CFH* (complement factor H) or *CFI* (complement factor I). This disorder leads to damage in small blood vessels, affecting kidneys, brain, and other organs. Complement inhibitors are also used to manage symptoms and prevent progression.

Complement-related disorders can also contribute to autoimmune diseases like **lupus nephritis** or **myasthenia gravis**, where overactive complement pathways contribute to tissue damage. Research into complement inhibitors has expanded therapeutic options, offering targeted treatments to modulate immune responses without broadly suppressing immunity.

Diagnosis often involves genetic testing, complement activity assays, and clinical evaluations. Management focuses on controlling complement overactivity, managing symptoms, and preventing complications. Ongoing research continues to uncover new mechanisms and potential treatments for complement-related conditions.