Describe the most common red blood cell inclusions and their composition, relating each inclusion to clinical conditions in which they may be found.
Howell-Jolly bodies: nuclear remnants containing DNA that are 1 to 2µm in size and appear singly or doubly on the periphery of the cell membrane (surgical splenectomy, thalassemic syndromes, sickle cell anemia, megaloblastic anemias)
basophilic stippling: ribosomal and mitochondrial remnants produce a fine blue dusting or coarse dots around the periphery of RBCs (alcoholism, thalassemia syndromes, megaloblastic anemias, arsenic intoxication, lead poisoning)
Pappenheimer bodies (siderotic granules when seen in a stain other than Wright-Giemsa): small, irregular magenta inclusions seen along the periphery of red cells (any condition with iron overloading, hemoglobinopathies, splenectomy)
Heinz bodies: resulting from denatured/precipitated hemoglobin (alpha thalassemic syndroms, G6PD deficiency, unstable hemoglobin syndromes)
Cabot rings: figure-8 conformations (megaloblastic anemias, dyserythropoiesis, homozygous thalassemia, postsplenectomy)