Anaplasma marginale
Morphology: small, round, dark purple inclusions located at the periphery of red cells. Usually 1 – 2 bacteria per red cell. Present in up to 90% of red cells. Look alike: Howell-Jolly… Read more Anaplasma marginale →
Rouleaux
Morphology: stacks of red blood cells (like a stack of coins). Look alike: agglutination. Rouleaux can be distinguished from agglutination with a saline dilution test: place one drop of blood on a… Read more Rouleaux →
Agglutination
Morphology: three-dimensional clumps of red blood cells. Caused by antibodies binding red blood cells together. Look alike: rouleaux. Agglutination can be distinguished from rouleaux with a saline dilution test: place one drop… Read more Agglutination →
Heinz Bodies
Morphology: dense round granules at the periphery of a red blood cell. Result from oxidant injury to red blood cells which causes hemoglobin to precipitate and form intracellular inclusions. Commonly seen… Read more Heinz Bodies →
Eccentrocytes
Morphology: red blood cells with a clear crescent-shaped area along one side of the periphery. Formed by the fusion of two layers of oxidized cell membrane with no hemoglobin in between.… Read more Eccentrocytes →
Echinocytes
Morphology: red blood cells with small, regular spicules projecting from the cell surface. Spicules are uniform in shape with sharp or blunt tips, uniform in length, and evenly spaced around the… Read more Echinocytes →
Acanthocytes
Morphology: red blood cells with irregular spicules projecting from the cell surface. Spicules are variable in shape (blunt or bulbous tips), variable in size, and unevenly distributed around the periphery of… Read more Acanthocytes →
Cells and Smears 