SM_248b: Acquired Hemolytic Anemias Flashcards
____ is premature destruction of RBCs
Hemolysis is premature destruction of RBCs
- Normal RBC life span is 90-120 days
Hemolytic anemia occurs when ___
Hemolytic anemia occurs when rate of RBC destruction exceeds production
Describe the types of hemolytic anemias
Hemolytic anemias

Describe intracorpuscular hemolysis
Intracorpuscular hemolysis
- Hemoglobinopathies: sickle cell anemia, hemoglobin C or E
- Enzyme defects: G6PD deficiency, pyruvate kinase deficiency
- Membrane abnormalities: hereditary spherocytosis / elliptocytosis, acanthocytosis (spur cell anemia), paraxosymal nocturnal hemoglobinuria
____ and ____ are intracorpuscular causes of hemolysis
Acanthocytosis (spur cell anemia) and paroxysmal nocturnal hemoglobinuria are intracorpuscular causes of hemolysis
Describe extracorpuscular hemolysis
____ and ____ are extracorpuscular causes of hemolysis
Immunologic and infectious are extracorpuscular causes of hemolysis
Describe lab features of hemolytic anemia
Lab features of hemolytic anemia
- Anemia
- Reticulocytosis, polychromasia
- Decreased haptoglobin
- Hemoglobinuria or hemosiderinuria
- Indirect hyperbilirubinemia
- Elevated LDH
- Abnormal appearance of RBCs
These are ___

Normal RBCs

These are ____

Spherocytes

These are ____

Reticulocytes
- Immature RBCs
- No longer contain nucleus
- Have residual RNA
- Indicator of increased production of RBCs
- Not specific for hemolysis

This is ___

Polychromasia

Intravascular hemolysis results from ___
Intravascular hemolysis results from direct mechanical damage to RBCs
- Some immune-mediated hemolytic anemias, particularly complement-mediated destruction
Extravascular hemolysis occurs in the ___
Extravascular hemolysis occurs in the reticuloendothelial system
- Mononuclear phagocytes, particularly in spleen and liver
Describe intravascular and extravascular hemolysis

Intravascular and extravascular hemolysis

Describe acquired hemolytic anemias
Acquired hemolytic anemias
- Immune-mediated hemolytic anemia: warm or cold autoantibody, RBC alloantibodies
- Traumatic: microangiopathic hemolytic anemia, cardiac valvular disease
- Infections: malaria, babesiosis
- Membrane disorders: paroxysmal nocturnal hemoglobinuria, acanthocytosis
Warm antibody type of autoimmune hemolytic anemia involves antibody reaction at ___ and ___ hemolysis
Warm antibody type of autoimmune hemolytic anemia involves antibody reaction at 37C and extravascular hemolysis
Cold antibody type of autoimmune hemolytic anemia involves antibody reaction at ___ and ___ hemolysis
Cold antibody type of autoimmune hemolytic anemia involves antibody reaction at 4C and intravascular hemolysis
- Complement-mediated
____ is used to diagnose autoimmune hemolytic anemia
Direct Coombs test is used to diagnose autoimmune hemolytic anemia
- Detects antibody or complement or RBCs
Direct Coombs test involves ____
Direct Coombs test involves anti-IgG / IgM / IgA or anti-complement binding to RBCs and causing clumping

Indirect Coombs test involves ___
Indirect Coombs test involves antiglobulin serum binding to patient antibodies and causing clumping

Describe warm-body hemolytic anemia
Warm body hemolytic anemia
- Idiopathic
- Lymphomas
- Collagen vascular diseases: SLE
- Drugs: alpha-methyldopa, penicillin, quinidine
- Post-viral infections
- Other: tumors

Warm antibody hemolytic anemia pathophysiology involves ____ that are then____
Warm antibody hemolytic anemia pathophysiology involves IgG antibodies coating RBCs that are then removed by macrophages in spleen
- 25% associated with underlying disease

Describe lab findings of warm antibody hemolytic anemia
Warm antibody hemolytic anemia
- Spherocytes / microspherocytes
- Anemia
- Reticulocytosis: nucleated RBCs
- Indirect hyperbilirubinemia, elevated LDH, decreased haptoglobin
- Coombs test: IgG usually postive, complement can be positive or negative








