Warm autoimmune hemolytic anemia

This code identifies a type of autoimmune hemolytic anemia characterized by the presence of autoantibodies that react optimally at body temperature (warm-reacting antibodies). These antibodies bind to red blood cells, leading to their premature destruction and resulting in anemia. It is an acquired disorder where the immune system mistakenly attacks the body's own red blood cells.

Assign this code when documentation explicitly states "warm autoimmune hemolytic anemia" or "warm AIHA." This diagnosis is typically supported by laboratory findings such as a positive direct antiglobulin test (DAT) with IgG and/or C3d, spherocytes on peripheral smear, and evidence of hemolysis.

• Do not use this code for other types of autoimmune hemolytic anemia, such as cold agglutinin disease (D59.12).
• Ensure documentation specifies "warm" to differentiate from other autoimmune hemolytic anemias.
• Code any underlying conditions causing secondary warm AIHA, such as systemic lupus erythematosus or lymphoma, as primary diagnoses if applicable, with D59.11 as a secondary diagnosis.