Autoimmune hemolytic anemia.
Warm-type autoantibodies of autoimmune hemolytic anemia (AIHA) are usually IgG but may be IgM or IgA. They are usual Rh specific. Cold-type antibodies are IgM or IgG  (Donath-Landsteiner [DL] antibody). IgM antibodies are usually anit-l (occasionally anti-i) and DL antibodies anti-P. The warm IgG antibodies do not fix complement (C); they cause red blood cell (RBC) destruction predominantly in the spleen as the result of interaction between fixing; they cause RBC destruction either by intravascular lysis (complement sequence completed) or by interaction between C3-coated RBCs and phagocytes in liver and spleen. Gentic factors, immunoglobulin deficiency, somatic mutation, viral infections and drugs, and failure of T-lymphocyte function, all probably play a part in breaking immunological tolerance and the development of AIHA.
D000744:Anemia, Hemolytic, Autoimmune / Q000139:chemically induced / Q000209:etiology / Q000276:immunology* / Q000601:surgery; D001323:Autoantibodies / Q000032:analysis*; D003080:Cold Temperature; D004912:Erythrocytes / Q000276:immunology; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D007153:Immunologic Deficiency Syndromes / Q000150:complications; D007239:Infections / Q000150:complications; D008223:Lymphoma / Q000150:complications; D008750:Methyldopa / Q000009:adverse effects; D010586:Phagocytes / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013934:Thymectomy
D001323:Autoantibodies; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D008750:Methyldopa