autoimmune hemolytic anemia
Quick Summary
Autoimmune hemolytic anemia (AIHA) is a condition where the body's immune system mistakenly attacks and destroys its own red blood cells. This self-attack is due to the formation of autoantibodies against red blood cells, leading to hemolysis, or the breakdown of these cells.12
AIHA can be triggered by various factors, including infections like Mycoplasma pneumoniae or by certain medications such as alpha methyldopa, quinine, sulfonamides, or penicillin. The autoantibodies are categorized as either warm-reacting (active at body temperature) or cold-reacting (active at lower temperatures). Warm-reacting antibodies cause about 80% of AIHA cases and are typically of the IgG class, while cold-reacting antibodies are mainly IgM and can be activated by exposure to cold.2
While the immune system usually distinguishes between self and non-self, errors can lead to autoimmunity. The presence of autoantibodies doesn't always mean disease; it's the resulting dysfunction that defines an autoimmune disorder.2
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