Macrocytes
Morphology: red blood cells that are larger than normal, may be hypochromic or normochromic. Look alike: polychromatophils (also larger than normal but stain dark purple). Commonly seen with: other features of… Read more Macrocytes →
Torocytes
Morphology: red blood cells with increased central pallor and a normal thick rim of hemoglobin creating a “punched out” appearance. Look alikes: codocytes (bullseye), hypochromasia (increased central pallor with thin rim of… Read more Torocytes →
Codocytes
Also called: target cells Morphology: canine red blood cells with a bullseye appearance. Caused by increased ratio of cell membrane to hemoglobin content which results in a central bulge. Look alike:… Read more Codocytes →
Reticulocytes
Morphology: immature red blood cells that stain blue with new-methylene blue due to precipitation of retained cytoplasmic RNA. Aggregate reticulocytes are less mature with large amounts of RNA that form dark… Read more Reticulocytes →
Polychromatophils
Morphology: immature red blood cells that stain dark purple on Romanowsky stains (Wright’s, Diff-Quick) due to retained cytoplasmic RNA. Larger than normal red cells. Commonly seen with: features of regenerative anemia (macrocytosis,… Read more Polychromatophils →
Keratocytes
Also called: blister cells (vesicle), helmet cells (ruptured) Morphology: red blood cells with a blister-like vesicle on the margin, or a bite-shaped defect with horn-like projections on the margin (which results… Read more Keratocytes →
Schizocytes
Also called: schistocytes Morphology: red blood cell fragments. Usually oblong with irregular margins, but may appear in a variety of shapes and sizes. Commonly seen with: keratocytes and acanthocytes (if caused by… Read more Schizocytes →
Basophilic Stippling
Morphology: numerous small, blue, punctate inclusions in red blood cells. Caused by spontaneous aggregation of ribosomes in the cytoplasm. Look alike: Mycoplasma Commonly seen with: features of regenerative anemia (macrocytes, anisocytosis, polychromatophils), features… Read more Basophilic Stippling →
Cells and Smears 