Primary Hematopoietic and Lymphoid Tissue ›› Bone Marrow ›› Myeloid ›› Granulocytes & Precursors ›› Abnormal
Promyelocyte with Auer Rods
›Microscopic Features:
- 3-4x larger than a mature RBC
- High nuclear to cytoplasmic ratio
- Round Nucleus with immature chromatin (not clumped)
- Prominent nucleoli
- Cytoplasm is not as scant as myeloblast, gray to pale blue with primary granules
- Multiple Auer rods may be seen as well
›Normal % blood-PB, marrow-BM, lymphoid tissue-LN:
- PB: None
- BM: None
- LN: None
›May Resemble:
›Differential Diagnoses:
If in blood or in bone marrow:
Acute Promyelocytic Leukemia (APL)
Acute Promyelocytic Leukemia (APL)
›Classic Immunophenotype:
- CD34-
- CD117+
- HLA-DR-
- CD13+
- CD33+
- (they may have immunophenotypic aberrancies such as gain of CD56, etc.)
›Cartoon Image:
Click and drag
for direct comparison
for direct comparison
›Misc:
Promyelocyte with multiple Auer rods are called a "Faggot cell" (Faggot meaning "Bundle of Sticks", the numerous auer rods resemble such)