Cytoplasmic Variations

Toxic Granulation

  • Toxic granulation is manifested by the presence of large granules in the cytoplasm of segmented and band neutrophils in the peripheral blood. The color of these granules can range from dark purplish blue to an almost red appearance.

  • Toxic granules are azurophilic granules normally present in early myeloid forms, but which are not normally seen at the band and segmented stages of neutrophil maturation. These granules contain peroxidases and hydrolases.

  • Toxic granulation is seen in cases of severe infection, as a result of denatured proteins in rheumatoid arthritis or, less frequently, as a result of autophagocytosis. Infection is the most frequent cause of toxic granulation.

  • This type of granulation may be seen in cells which also contain Dohle bodies and/or vacuoles. Cells containing toxic granules may have decreased numbers of specific granules.

  • Cells containing only a few specific granules, with or without toxic granules, are said to be degranulated. The nucleus in degranulated cells may often be round-bilobed, smooth and pyknotic. This type of nucleus is the result of aging and will disintegrate soon.

  • Increased basophilia of azurophilic granules simulating toxic granules may occur in normal cells with prolonged staining time or decreased pH of the stain.

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