Hemolysis: Causes, Symptoms, Diagnosis, Treatment, and Prevention
The medical term hemolysis refers to the destruction of red blood cells (RBCs). RBCs carry oxygen from your lungs to the rest of your body, making them a vital part of your blood. When your spleen removes old or damaged RBCs, your body produces new ones. In some cases, however, hemolysis can occur faster than your body can make new RBCs, resulting in hemolytic anemia.
Causes of Hemolysis
Hemolysis can be caused by various factors, either intrinsic or extrinsic. Intrinsic causes are related to defects or abnormalities in the RBCs themselves, such as:
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Genetic disorders, such as sickle cell anemia, thalassemia, or hereditary spherocytosis, that affect the shape, size, or structure of the RBCs.
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Enzyme deficiencies, such as glucose-6-phosphate dehydrogenase (G6PD) deficiency or pyruvate kinase deficiency, that impair the metabolism or energy production of the RBCs.
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Hemoglobinopathies, such as hemoglobin C or E, that alter the function or stability of the hemoglobin molecule, which carries oxygen in the RBCs.
Extrinsic causes are related to factors outside the RBCs, such as:
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Infections, such as malaria, babesiosis, or clostridium, that invade or damage the RBCs.
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Medications, such as penicillin, acetaminophen, or quinine, that trigger an immune reaction against the RBCs or interfere with their function.
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Toxins, such as lead, copper, or snake venom, that poison or rupture the RBCs.
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Immune disorders, such as autoimmune hemolytic anemia (AIHA) or hemolytic disease of the newborn (HDN), that cause your body to produce antibodies that attack your own or foreign RBCs.
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Mechanical trauma, such as artificial heart valves, hemodialysis, or heart-lung bypass machines, that shear or crush the RBCs as they pass through.
Symptoms of Hemolysis
The symptoms of hemolysis depend on the severity and duration of the condition, as well as the underlying cause. Some common symptoms include:
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Fatigue, weakness, or dizziness
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Pale or yellow skin or eyes (jaundice)
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Dark or red urine (hemoglobinuria)
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Shortness of breath or chest pain
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Rapid or irregular heartbeat
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Enlarged spleen or liver
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Fever or chills
Diagnosis of Hemolysis
To diagnose hemolysis, your doctor will ask you about your medical history, symptoms, and medications. They will also perform a physical examination and order some blood tests, such as:
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Complete blood count (CBC), which measures the number and size of your RBCs, as well as the levels of hemoglobin and hematocrit (the percentage of RBCs in your blood). Hemolysis can cause low RBC count, low hemoglobin, and low hematocrit.
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Reticulocyte count, which measures the number of immature RBCs in your blood. Hemolysis can cause high reticulocyte count, as your body tries to make more RBCs to compensate for the loss.
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Peripheral blood smear, which examines the shape and appearance of your RBCs under a microscope. Hemolysis can cause abnormal or fragmented RBCs, such as spherocytes, schistocytes, or sickle cells.
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Lactate dehydrogenase (LDH) level, which measures the enzyme that is released when RBCs are destroyed. Hemolysis can cause high LDH level.
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Haptoglobin level, which measures the protein that binds to hemoglobin when RBCs are destroyed. Hemolysis can cause low haptoglobin level.
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Bilirubin level, which measures the pigment that is produced when hemoglobin is broken down. Hemolysis can cause high bilirubin level, especially the indirect or unconjugated type.
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Direct antiglobulin test (DAT) or Coombs test, which detects the presence of antibodies or complement proteins on the surface of your RBCs. Hemolysis can cause a positive DAT, indicating an immune-mediated cause.
Depending on the results of these tests, your doctor may order further tests to identify the specific cause of hemolysis, such as:
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Genetic tests, which look for mutations or abnormalities in the genes that code for RBC components, such as hemoglobin, enzymes, or membrane proteins.
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Blood cultures, which check for the presence of bacteria or parasites in your blood that may cause hemolysis.
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Blood typing and crossmatching, which determine your blood group and Rh factor, and test the compatibility of your blood with donor blood for transfusion.
Treatment of Hemolysis
The treatment of hemolysis depends on the cause and severity of the condition, as well as your overall health and preferences. Some possible treatment options include:
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Treating the underlying cause, such as antibiotics for infections, chelation therapy for lead poisoning, or surgery for mechanical trauma.
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Stopping or changing the medications that may cause hemolysis, under the guidance of your doctor.
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Taking supplements of iron, folic acid, or vitamin B12, which are essential for RBC production and function.
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Receiving blood transfusions, which provide healthy RBCs to replace the ones that are destroyed. This may require immunosuppressive drugs or special filters to prevent further hemolysis or reactions.
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Taking corticosteroids, which suppress your immune system and reduce the inflammation and destruction of your RBCs. This is mainly used for AIHA or HDN.
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Taking immunoglobulins, which are antibodies that block the action of your own antibodies that attack your RBCs. This is mainly used for AIHA or HDN.
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Undergoing splenectomy, which is the surgical removal of your spleen. This may reduce the rate of hemolysis, especially for extravascular causes. However, this also increases your risk of infections, so you may need vaccinations and antibiotics.
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Undergoing stem cell transplantation, which is the infusion of healthy stem cells from a donor into your bone marrow. This may cure some genetic causes of hemolysis, such as sickle cell anemia or thalassemia. However, this is a risky and complex procedure that requires a compatible donor and immunosuppressive drugs.
Prevention of Hemolysis
Some forms of hemolysis are not preventable, such as those caused by genetic disorders. However, you may be able to prevent or reduce the risk of hemolysis by:
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Avoiding or limiting exposure to medications, toxins, and infections that may cause hemolysis. You should consult your doctor before taking any new drugs or supplements, and follow the prescribed dosage and instructions. Also, practice good hygiene and get vaccinated against preventable diseases.
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Getting regular check-ups and blood tests to monitor your RBC count and hemoglobin level, and reporting any symptoms or changes in your condition to your doctor.
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Drink plenty of fluids, avoid alcohol, and consume a balanced and nutritious diet that provides iron, folic acid, and vitamin B12.
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You should also avoid activities that may cause physical trauma or exertion to your RBCs, such as contact sports and high-altitude travel, to improve your overall health and well-being.
