Warm autoinumne hemolytic anaemia may be seen in all of the following conditions except :

Answer is D (Mycoplasma Pneumonia) Mycoplasma pneumoniae infections are associated with a cold antibody haemolytic anemia Autoimmune hemolytic anemias are characterized by formation of autoantibodies against patient's own red cells. Depending upon reactivity of autoantibodies these are fuher divided into two types. Warm Antibody Hemolytic Anemia Cold Antibody Hemolytic Anemia * Antibodies here bind with antigens (on RBC) at * Antibodies here bind with antiens (on RBC) better at body temperature (37degC) temperatures lower than 37degC * These antibodies are called warm antibodies and are * These antibodies are called cold reactive antibodies and are nearly IgG (Rarely IgM or IgA) usually IgM Q Causes Causes 1. Idiopathic 1. Acute: Mycoplasma infection Q Infectious mononucleosis e 2. Lymphomas: CLL Q,Non-Hodgkins, etc 2. Chronic : IdiopathicQ 3. SLE deg and other Collagen Vascular Diseases 3. Paroxysmal cold hemoglobinuria e 4. Drugs: eg. a MethyldopaQ Mechanism of Hemolysis Mechanism of Hemolysis Human red cells cooled with IgG are trapped by splenic Antibodies of IgM type bind on Red cell surface and cause macrophages - red cell destruction agglutination. Hemolytic effect is mediated through fixation of C3 to RBC surface.Q Diagnosis Diagnosis Positive direct Coomb's test, at 37degC for presence of Positive direct Coomb's test for detection of C3 on the red cell warm antibodies on surface of Red cellQ surface but 1gM responsible for coating on red cells is not Positive Indirect Coomb's test at 37degC for presence of large quantities of warm antibodies in serum. Q found. Q