A patient with autoimmune hemolytic anemia experiences increased red blood cell destruction. Which mechanism explains why IgG autoantibodies cause this destruction?

💡 Explanation

In autoimmune hemolytic anemia, IgG autoantibodies bind to red blood cells, which then triggers complement activation, leading to membrane attack complex formation and cell lysis, because complement-mediated lysis directly destroys the cells. Therefore complement activation explains the destruction, rather than direct T-cell cytotoxicity or erythropoietin receptor blockade, which are less common mechanisms in this condition.

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