Which condition is most likely associated with autosplenectomy?

Sickle cell disease is most closely associated with autosplenectomy, which is the process by which the spleen becomes fibrotic and nonfunctional due to repeated splenic infarctions. In sickle cell disease, the abnormal hemoglobin (hemoglobin S) can polymerize under low-oxygen conditions, causing red blood cells to become rigid and sickle-shaped. These abnormal cells can occlude blood vessels, leading to ischemia and damage to the spleen over time.

In sickle cell patients, the repeated splenic damage reduces the spleen's ability to function effectively, which can ultimately lead to its auto-removal from circulation as a functioning organ—this is what is meant by autosplenectomy. The loss of spleen function put these patients at greater risk for infections, particularly with encapsulated organisms, due to the spleen's role in filtering bacteria from the blood and generating a protective immune response.

Understanding the link between sickle cell disease and autosplenectomy is crucial for managing patients who may have increased susceptibility to infections and require appropriate vaccinations and prophylactic measures. The other conditions, while they may affect blood cells or the splenic system, do not typically lead to the same degree of splenic dysfunction as sickle cell disease does