Hemolytic anemia
Alternative Names
Anemia - hemolytic
Definition
Anemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues.
Normally, red blood cells last for about 120 days in the body. In hemolytic anemia, red blood cells in the blood are destroyed earlier than normal.
Causes
Hemolytic anemia occurs when the bone marrow is unable to replace the red blood cells that are being destroyed.
Immune hemolytic anemia occurs when the immune system mistakenly sees your own red blood cells as foreign substances. Antibodies then develop against the red blood cells. These antibodies attack the red blood cells and cause them to break down too early.
Red blood cells may be destroyed due to:
- Genetic defects within the red cells (such as sickle cell anemia, thalassemia, and G6PD deficiency)
- Exposure to certain chemicals, drugs, and toxins
- Infections
Other causes are:
- Blood clots in small blood vessels
- Transfusion of blood from a donor with a blood type that does not match yours
Symptoms
You may not have symptoms if the anemia is mild. If the problem develops slowly, the first symptoms may be:
- Feeling grumpy
- Feeling weak or tired more often than usual, or with exercise
- Headaches
- Problems concentrating or thinking
If the anemia gets worse, symptoms may include:
- Blue color to the whites of the eyes
- Brittle nails
- Light-headedness when you stand up
- Pale skin color
- Shortness of breath
- Sore tongue
Exams and Tests
A test called a complete blood count (CBC) can help diagnose anemia and offer some hints to the type and cause of the problem. Important parts of the CBC include red blood cell count (RBC), hemoglobin, and hematocrit (HCT).
These tests can identify the type of hemolytic anemia:
- Absolute reticulocyte count
- Coomb test, direct
- Coomb test, indirect
- Donath-Landsteiner test
- Cold agglutinins
- Free hemoglobin in the serum or urine
- Hemosiderin in the urine
- Platelet count
- Protein electrophoresis - serum
- Pyruvate kinase
- Serum haptoglobin levels
- Serum LDH
- Urine and fecal urobilinogen
Treatment
Treatment depends on the type and cause of the hemolytic anemia:
- In emergencies, a blood transfusion may be needed.
- For an overactive immune system, drugs that suppress the immune system may be used.
- When blood cells are being destroyed at a fast pace, the body may need extra folic acid and iron supplements to replace what is being lost.
In rare cases, surgery is needed to take out the spleen. This is because the spleen acts as a filter that removes abnormal cells from the blood.
Outlook (Prognosis)
Outcome depends on the type and cause of hemolytic anemia. Severe anemia can make heart disease, lung disease, or cerebrovascular disease worse.
When to Contact a Medical Professional
Call your health care provider if you develop symptoms of hemolytic anemia.
References
Jager U, Lechner K. Autoimmune hemolytic anemia. In: Hoffman R, Benz EJ Jr, Silberstein LE, et al., eds. Hematology: Basic Principles and Practice. 6th ed. Philadelphia, Pa: Elsevier Saunders; 2012:chap 44.
Price EA, Schrier SS. Extrinsic nonimmune hemolytic anemias. In: Hoffman R, Benz EJ Jr, Silberstein LE, et al., eds. Hematology: Basic Principles and Practice. 6th ed. Philadelphia, Pa: Elsevier Saunders; 2012:chap 45.