The spleen normally removes abnormal and aged RBCs from the circulation, including RBCs released prematurely from bone marrow containing remnants of DNA (Howell-Jolly bodies) and denatured haemoglobin (Heinz bodies). Howell-Jolly and Heinz bodies are rarely seen in normal peripheral blood, but are seen in a significant percentage of RBCs in subjects with hyposplenism. Thrombocytosis and monocytosis are often present.