Health Library

Hemolytic crisis

Hemolysis - acute

Hemolytic crisis occurs when large numbers of red blood cells are destroyed over a short time. The loss of red blood cells occurs much faster than the body can produce new red blood cells.

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Considerations

During a hemolytic crisis, the body cannot make enough red blood cells to replace those that are destroyed. This causes acute and often severe anemia.

The part of red blood cells that carries oxygen (hemoglobin) is released into the bloodstream. This can lead to kidney damage.

Causes

Causes of hemolysis include:

• A lack of certain proteins inside red blood cells
• Autoimmune diseases
• Certain infections
• Defects in the hemoglobin molecules inside red blood cells
• Defects of the proteins that make up the internal framework of red blood cells
• Side effects of certain medicines
• Reactions to blood transfusions

When to Contact a Medical Professional

Contact your health care provider if you have:

• Symptoms of anemia, including pale skin or fatigue, especially if these symptoms get worse
• Urine that is red, red-brown, or brown (tea-colored)

What to Expect at Your Office Visit

Emergency treatment may be necessary. This may include a hospital stay, oxygen, blood transfusions, and other treatments.

When your condition is stable, your provider will perform a physical exam and ask about your medical history and symptoms. The physical exam may show swelling of the spleen (splenomegaly).

Tests that may be done include:

• Blood chemistry panel
• Complete blood count (CBC)
• Coombs test
• Haptoglobin
• Lactate dehydrogenase

Treatment depends on the cause of hemolysis.

Related Information

References

Elghetany MT, Banki K. Erythrocytic disorders. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 33.

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.

Michel M. Autoimmune and intravascular hemolytic anemias. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 146.

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.

Review Date: 1/29/2026  

Reviewed By: Warren Brenner, MD, Oncologist, Lynn Cancer Institute, Boca Raton, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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