II. Type: Warm Antibody (IgG mediated, more common)
- Mechanism
- IgG binds RBCs typically at Rh complex at 37 C (Body Temperature)
- Reticuloendothelial Macrophages ingest IgG-bound membrane
- Form microspherocytes which are trapped by Spleen (may result in Splenomegaly)
- Causes
- Idiopathic Hemolytic Anemia (most common)
- Non-Hodgkin's Lymphoma
- Chronic Lymphocytic Leukemia (CLL)
- Systemic Lupus Erythematosus (SLE)
- Human Immunodeficiency Virus (HIV)
- Drug Induced Immune-Mediated Hemolysis
III. Type: Cold Antibody (IgM and complement mediated)
- Mechanism
- IgM transiently binds RBCs at 32 C (cold)
- Activates complement and C3 binds RBC membrane at PolysaccharideAntigens
- C3 bound RBCs are lysed on rewarming and are cleared by the liver
- Causes
- Human Immunodeficiency Virus (HIV)
- Mycoplasma pneumonia or other infection
- Infectious Mononucleosis
- Lymphoma
- Idiopathic
IV. Type: Paroxysmal (Cold Hemolysis mediated by IgG)
- See Paroxysmal Cold Hemoglobinuria
- Causes
- Tertiary Syphilis
- Acute Viral Infection (Mumps, Measles)
V. Labs
- Direct Coombs Test positive
VI. Management
-
General
- Consult with Hematology
- Blood Product transfusions
- Cold Hemolysis
- Avoid cold exposure
- Supportive management
- Warm Hemolysis
- Corticosteroids (e.g. Prednisone 1-1.5 mg/kg/day)
- Splenectomy
- Immunosuppressants
- Danazol
- Intravenous Immunoglobulin
- Plasma exchange
VII. References
- Schreiber in Goldman (2000) Cecil Medicine, p. 876-82
- Dhaliwal (2004) Am Fam Physician 69:2599-606 [PubMed]
- Petz (2001) Curr Opin Hematol 8(6):411-6 [PubMed]
- Phillips (2018) Am Fam Physician 98(6): 354-61 [PubMed]