Hereditary Spherocytosis

Hereditary spherocytosis is a genetic condition that affects the red blood cells, which are responsible for carrying oxygen throughout the body. In this disorder, the red blood cells become abnormally shaped like spheres instead of their usual disc shape. These spherical cells are less flexible and more fragile, causing them to break down more easily. This leads to a shortage of red blood cells, known as anemia, which can cause symptoms like fatigue, pale skin, and jaundice. The condition primarily affects the blood and spleen, as the spleen removes the damaged cells from circulation. People with this condition may also experience episodes of enlarged spleen and gallstones due to increased breakdown of red blood cells.

Hereditary spherocytosis is a congenital hemolytic anemia characterized by the presence of spherocytes—red blood cells with decreased membrane surface area leading to a spherical shape and increased fragility. It is most commonly caused by mutations in genes encoding red cell membrane proteins such as ANK1, SPTA1, SPTB, SLC4A1, and EPB42, resulting in defective vertical membrane cytoskeleton interactions. This defect causes premature destruction of red blood cells primarily in the spleen, leading to extravascular hemolysis. Clinically, patients present with anemia, jaundice, splenomegaly, and sometimes gallstones due to chronic hemolysis. The severity ranges from mild to severe depending on the specific mutation and degree of membrane protein deficiency. Laboratory findings include increased mean corpuscular hemoglobin concentration (MCHC), reticulocytosis, and spherocytes on peripheral smear. The condition is inherited in an autosomal dominant pattern in most cases but can also be autosomal recessive.