Cabot rings appear as thin, red-violet-staining strands in the shape of rings, figure eights, or shapes of the letter B on Wright-stained smears. They are rarely seen in peripheral blood. The rings are probably microtubules from the mitotic spindle that remain behind after the rest of the erythrocyte nucleus is extruded.
Cabot rings have been observed in megaloblastic anemia, lead poisoning, severe anemia, leukemia, myelodysplastic syndromes, and other cases of dyserythropoiesis.
