The spleen performs a large number of important functions including processing and removal of opsonized pathogens, cellular maintenance, immunoglobulin production and the removal of effete worn out red blood cell. When removed either through trauma or for therapeutic indications the risk of overwhelming post splenectomy infection (OPSI) increases significantly; up to 58 times the general population in the setting of trauma and up to 1,100 times increased risk when for thalassaemia.