Complement-mediated thrombotic microangiopathy associated with lupus nephritis.

Complement-mediated thrombotic microangiopathy (CM-TMA) is a clinical disorder driven by the generation of excess complement. It is characterized by thrombocytopenia and microangiopathic hemolytic anemia (MAHA) with microvascular thrombosis resulting in systemic organ damage (TMA). One form of CM-TMA, atypical hemolytic uremic syndrome (aHUS), is characterized by pathologic complement activation due to the loss of the natural regulators of the complement system, which results in systemic endothelial and organ damage.