Promyelocyte
- Size : Large, 20 µm
- N/C ratio= Medium, 0.5
- Cytoplasm
- Extension : Abundant
- Basophilia : Intense
- Number of granules : Numerous
- Color of granules : Red = azurophils
- Membrane : Regular
- Nucleus
- Situation : Eccentric
- Chromatin : Fine
- Nucleoli : Present
- Membrane : Regular
- Normal values : Absent in the blood, quite rare in the bone marrow
- Description / Pathology :
Large cell, round eccentric nucleus, quite fine chromatin with nucleolus, very basophilic cytoplasm with light perinuclear area and many primary azurophil granules covering the cytoplasm and nucleus. Absence of Auer bodies.
Present in the blood in high myelemia (CML + +)
A promyelocytic excess with granulocytic maturation blockage can be found in the bone marrow in case of toxic neutropenia.