What does hemolysis mean?

Hemolysis refers to the premature rupture of red blood cells in the bloodstream, caused by various factors inside or outside the body, resulting in the release of hemoglobin, which is termed hemolysis.

Hemolysis can be divided into two major categories: intravascular hemolysis and extravascular hemolysis. Intravascular hemolysis is usually caused by immune, infectious, or physicochemical factors, such as autoimmune hemolytic anemia and paroxysmal nocturnal hemoglobinuria; extravascular hemolysis mainly occurs in the spleen and is commonly seen in inherited red blood cell membrane or enzyme deficiency disorders, such as hereditary spherocytosis and thalassemia.

After hemolysis, patients may experience symptoms such as jaundice, decreased hemoglobin levels, anemia, hepatosplenomegaly, lethargy, and fever. Severe cases can even lead to acute kidney injury. Depending on the degree and speed of hemolysis, clinical manifestations may vary. For example, acute hemolysis may present with sudden high fever, dyspnea, and dark brown (like soy sauce) urine, while chronic hemolysis mainly manifests as anemia, jaundice, and splenomegaly.