Hemolytic anemia

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 people with hemolytic anemia, red blood cells in the blood are destroyed earlier than normal.

Alternative Names

Anemia - hemolytic

Causes

The bone marrow is mostly responsible for making new red cells. Bone marrow is the soft tissue in the center of bones that helps form all blood cells.

Hemolytic anemia occurs when the bone marrow isn't making enough red cells to replace the ones that are being destroyed.

There are several possible causes of hemolytic anemia. Red blood cells may be destroyed due to:

An autoimmune problem in which the immune system mistakenly sees your own red blood cells as foreign substances and destroys them
Genetic variations within the red cells (such as sickle cell anemia, thalassemia, and G6PD deficiency)
Exposure to certain chemicals, medicines, and toxins
Infections
Blood clots in small blood vessels
Transfusion of blood from a donor with a blood type that does not match yours
Faulty, damaged, or artificial heart valves

Symptoms

You may not have symptoms if the anemia is mild. If the problem develops slowly, the first symptoms may be:

Feeling weak or tired more often than usual, or with exercise
Feelings that your heart is pounding or racing
Headaches
Problems concentrating or thinking

If the anemia gets worse, symptoms may include:

Lightheadedness when you stand up
Pale skin
Shortness of breath
Sore tongue
Left upper abdominal pain due to an enlarged spleen

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:

Treatment

Treatment depends on the type and cause of the hemolytic anemia:

In emergencies, a blood transfusion may be needed.
For immune causes, medicines 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)

The 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

Contact your health care provider if you develop symptoms of hemolytic anemia.

References

Araten DJ, Brodsky RA. Paroxysmal nocturnal hemoglobinuria. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 32.

Gallagher PG. Hemolytic anemias: red blood cell membrane and metabolic defects. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 147.

Kumar V, Abbas AK, Aster JC, Deyrup AT, Das A. Hematopoietic and lymphoid systems. In: Kumar V, Abbas AK, Aster JC, Deyrup AT, Das A, eds. Robbins and Kumar Basic Pathology. 11th ed. Philadelphia, PA: Elsevier; 2023:chap 10.

Mentzer WC, Schrier SL. Extrinsic nonimmune hemolytic anemia. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 48.

Michel M, Jäger U. Autoimmune hemolytic anemia. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 47.