Asplenia

Asplenia and splenic hypoplasia refer to the complete or partial lack of splenic tissue. Congenital asplenia is a rare life-threatening condition, often presenting with pneumococcal sepsis. It may arise as part of situs abnormalities, or result from an unrelated specific defect of spleen development. The mode of inheritance is usually autosomal dominant. Rarely, a recessive inheritance and sporadic cases are reported. A wide range of diseases can affect the spleen. The spleen plays an important role in the defense against pathogens. Its rich and diverse population of immune cells and its anatomy enables optimal surveillance and phagocytosis of circulating blood elements. For patients suspected to have a spleen with diminished function, it is important to quantify their splenic function in order to assess the risk of developing overwhelming post-splenectomy syndrome and thromboembolic events, the treatment and prevention of which with antibiotics and vaccines is described in this chapter.