Anemia - hemolytic

Alternative names

Hemolytic anemia

Definition

Hemolytic anemia is a condition of an inadequate number of circulating red blood cells (anemia), caused by premature destruction of red blood cells. There are a number of specific types of hemolytic anemia which are described individually.

Causes, incidence, and risk factors

Hemolytic anemia occurs when the bone marrow is unable to compensate for premature destruction of red blood cells by increasing their production. When the marrow is able to compensate, anemia does not occur.

There are many types of hemolytic anemia, which are classified by the location of the defect. The defect may be in the red blood cell itself (intrinsic factor), or outside the red blood cell (extrinsic factor).

Causes of hemolytic anemia include infection, certain medications, autoimmune disorders, and inherited disorders. Types of hemolytic anemia include:

• Sickle-cell anemia
  
• Paroxysmal nocturnal hemoglobinuria
  
• Hemoglobin SC disease
  
• Hemolytic anemia due to G6PD deficiency
  
• Hereditary elliptocytosis
  
• Hereditary spherocytosis
  
• Hereditary ovalocytosis
  
• Idiopathic autoimmune hemolytic anemia
  
• Non-immune hemolytic anemia caused by chemical or physical agents
  
• Secondary immune hemolytic anemia
  
• Thalassemia
  

Symptoms

• Chills
  
• Fatigue
  
• Pale color
  
• Shortness of breath
  
• Rapid heart rate
  
• Yellow skin color (jaundice)
  
• Dark urine
  
• Enlarged spleen
  

Signs and tests
These are tests for hemolysis (red blood cell destruction). There are specific tests which identify the specific types of hemolytic anemia. They are performed after hemolysis has been established.

• Elevated indirect bilirubin levels
  
• Low serum haptoglobin
  
• Hemoglobin in the urine
  
• Hemosiderin in the urine