Sphärozytose

Sphärozytose refers to a condition where red blood cells become spherical in shape rather than their normal biconcave disc. This change in morphology is primarily caused by defects in the proteins that maintain the red blood cell membrane's structure and flexibility. The most common cause is hereditary spherocytosis, an inherited disorder characterized by mutations in genes encoding spectrin, ankyrin, or band 3 protein, which are crucial for the cytoskeleton of the red blood cell. Acquired spherocytosis can also occur, often as a result of autoimmune hemolytic anemia where antibodies target red blood cell membranes, leading to their destruction and the formation of spherocytes.

Spherocytes are less flexible than normal red blood cells and are more prone to destruction in the spleen. As they pass through the narrow splenic sinusoids, their altered shape and rigidity make them susceptible to being trapped and phagocytosed by splenic macrophages. This premature destruction of red blood cells leads to anemia. The severity of symptoms in spherocytosis can vary widely, from mild anemia to severe, life-threatening conditions. Common symptoms include fatigue, jaundice, and an enlarged spleen (splenomegaly). Diagnosis typically involves a blood smear showing spherocytes, along with tests to assess red blood cell fragility and hemolysis. Treatment strategies depend on the severity and underlying cause, and may include blood transfusions, folic acid supplementation, or surgical removal of the spleen (splenectomy) to reduce red blood cell destruction.