Description:

Small, irregularly shaped erythrocytes or fragments of erythrocytes (schizocytes).

Size:

Changeable.

Shape:

Dystrophic erythrocytes, including oval-, pear-, racket-, and tear-shaped, and crenated cells, with more or less marked irregular outlines.

Significance:     

Formed mainly by mechanical damage and deformation of particularly fragile erythrocytes. Poikilocytes can be found in pernicious anemia, and many other types of anemia. Neverhless, the type of poikilocytosis is specific for the anemia type - e.g., elongated, pencil shaped cells for iron deficiency anemia, pointed tear-shaped cells for megaloblastic anemias, and myelosclerosis and schizocytes for certain types of haemolytic anemia.