Hemolytic anemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells (RBCs), either in the blood vessels (intravascular hemolysis) or elsewhere in the human body (extravascular). This most commonly occurs within the spleen, but also can occur in the reticuloendothelial system or mechanically (prosthetic valve damage). Hemolytic anemia accounts for 5% of all existing anemias. It has numerous possible consequences, ranging from general symptoms to life-threatening systemic effects. The general classification of hemolytic anemia is either intrinsic or extrinsic. Treatment depends on the type and cause of the hemolytic anemia.Symptoms of hemolytic anemia are similar to other forms of anemia (fatigue and shortness of breath), but in addition, the breakdown of red cells leads to jaundice and increases the risk of particular long-term complications, such as gallstones and pulmonary hypertension. Signs and symptoms
Symptoms of hemolytic anemia are similar to the general signs of anemia. General signs and symptoms include: fatigue, pallor, shortness of breath, and tachycardia. In small children, failure to thrive may occur in any form of anemia. In addition, symptoms related to hemolysis may be present such as chills, jaundice, dark urine, and an enlarged spleen. Certain aspects of the medical history can suggest a cause for hemolysis, such as drugs, medication side effects, autoimmune disorders, blood transfusion reactions, the presence of prosthetic heart valve, or other medical illness.Chronic hemolysis leads to an increased excretion of bilirubin into the biliary tract, which in turn may lead to gallstones.
A positive Coombs test is a relative contraindication to transfuse the patient. In cold hemolytic anemia there is advantage in transfusing warmed blood. In severe immune-related hemolytic anemia, steroid therapy is sometimes necessary. In steroid resistant cases, consideration can be given to rituximab or addition of an immunosuppressant (azathioprine, cyclophosphamide). Association of methylprednisolone and intravenous immunoglobulin  can control hemolysis in acute severe cases. Sometimes splenectomy can be helpful where extravascular hemolysis, or hereditary spherocytosis, is predominant (i.e., most of the red blood cells are being removed by the spleen).Mitapivat was approved for medical use in the United States in February 2022. Other animals
Hemolytic anemia affects nonhuman species as well as humans. It has been found, in a number of animal species, to result from specific triggers.Some notable cases include hemolytic anemia found in black rhinos kept in captivity, with the disease, in one instance, affecting 20% of captive rhinos at a specific facility. The disease is also found in wild rhinos.Dogs and cats differ slightly from humans in some details of their RBC composition and have altered susceptibility to damage, notably, increased susceptibility to oxidative damage from consumption of onion. Garlic is less toxic to dogs than onion. References


== External links ==