Sicklecellanemi

Sicklecellanemi, commonly referred to as sickle cell anemia, is a hereditary blood disorder caused by a mutation in the beta-globin gene that leads to the production of hemoglobin S (HbS). It is inherited in an autosomal recessive pattern; individuals with two HbS alleles are typically affected, while those with one HbS allele have sickle cell trait and usually milder symptoms.

The abnormal HbS polymerizes when deoxygenated, causing red blood cells to become rigid and shaped like a sickle. These misshapen cells are prone to hemolysis and can occlude small blood vessels, leading to chronic anemia and episodes of acute pain known as vaso-occlusive crises. Over time, repeated sickling can cause organ damage, functional asplenia, and increased susceptibility to infection.

Clinical features include episodes of severe pain, fatigue from anemia, pallor, jaundice, and a higher risk of infections, particularly in childhood. Other problems may include acute chest syndrome, stroke, Priapism, splenic sequestration, leg ulcers, and avascular necrosis of bones. Growth and development may be affected in untreated children.

Diagnosis is often made by newborn screening or via hemoglobin electrophoresis or high-performance liquid chromatography, which detect HbS. Peripheral blood smear may show sickled cells; genetic testing confirms the diagnosis.

Management focuses on symptom relief, prevention of complications, and reversal of ongoing injury. Treatments include hydroxyurea to raise fetal hemoglobin levels, blood transfusions for severe anemia or prevention of stroke in high-risk individuals, vaccination and penicillin prophylaxis in children, hydration, and pain control during crises. Curative options such as hematopoietic stem cell transplantation exist for select patients. Newer therapies target different pathogenic steps, including inhibitors of HbS polymerization and modifiers of vascular adhesion.