Inclusion Body - Inclusion Bodies in Erythrocytes

Inclusion Bodies in Erythrocytes

Normally a red blood cell does not contain inclusions in the cytoplasm. However, it may be seen because of certain hematologic disorders.

There are three kinds of erythrocyte inclusions:

1. Developmental Organelles
   1. Howell-Jolly bodies: small, round fragments of the nucleus resulting from karyorrhexis or nuclear disintegration of the late reticulocyte and stain reddish-blue with Wright stain.
   2. Basophilic stipplings - this stipplings is either fine or coarse, deep blue to purple staining inclusion that appears in erythrocytes on a dried Wright stain.
   3. Pappenheimer bodies - are siderotic granules which are small, irregular, dark-staining granules that appear near the periphery of a young erythrocyte in a Wright stain.
   4. Polychromatophilic red cells - young red cells that no longer have nucleus but still contain some RNA.
   5. Cabot Rings - ring-like structure and may appear in erythrocytes in megaloblastic anemia or in severe anemias, lead poisoning, and in dyserythropoiesis, in which erythrocytes are destroyed before being released from the bone marrow.
2. Abnormal Hemoglobin Precipitation
   1. Heinz bodies - round bodies, refractile inclusions not visible on a Wright stain film. It is best identified by supravital staining with basic dyes.
   2. Hemoglobin H Inclusions - alpha thalassemia, greenish-blue inclusion bodies appear in many erythrocytes after four drops of blood is incubated with 0.5mL of Brilliant cresyl blue for 20 minutes at 37°C.
3. Protozoan Inclusion
   1. Malaria
   2. Babesia