1
Q
MPO
A
- myeloid diff
- stains primary (azurophilic) granules
- faint positivity may be seen in monoblasts
- negative in non-myeloid blasts
2
Q
Sudan Black B (SBB)
A
- myeloid diff
- stains lipid material
- faint positivity may be seen in monoblasts
- negative in non-myeloid blasts
3
Q
Chloroacetate esterase (CAE)
A
-positive in granulocytes only
4
Q
Nonspecific esterases (NSE)
A
- Includes alpha-naphthyl acetate (ANA) esterase and alpha-naphthyl butyrate (ANB) esterase*
- monocytic and megakaryocytic lineages
- monocyte staining can be inhibited by sodium fluoride (NaF)
5
Q
PAS
A
- lymphoblasts: shows “block” positivity, often encircling the nucleus in a “rosary bead” fashion
- some myeloblasts: diffuse granular staining
- erythroblasts (neoplastic only)
6
Q
Acid phosphatase (AP)
A
-positive in megakaryoblasts and lymphoid cells (dotlike)
7
Q
Oil Red O
A
-stains vacuoles of Burkitt
8
Q
Leukocyte alkaline phosphatase (LAP)
A
- 100 bands and PMNs are counted and scored on the intensity of cytoplasmic staining from 0-4
- sum of 100 cells is the LAP score
- normal 40-120
- CML have decreased LAP score (0-15)
- other causes of low score: PNH, some MDS, congenital hypophosphatasia, neonatal sepsis
- elevated levels (greater than 100) seen in leukemoid rxn, non-CML MPNs, glucocorticoid tx, pregnancy
9
Q
AML M0
A
All negative
M0: minimal differentiation
10
Q
AML M1-M3
A
MPO, SBB, CAE
- M1: minimal differentiation*
- M2: with maturation*
- M3: APL*
11
Q
AML M4
A
MPO, SBB, CAE, NSE
M4: myelomonocytic-includes eosinophilia
12
Q
AML M5
A
NSE only
M5: monoblastic/monocytic
13
Q
AML M6
A
MPO, SBB, PAS
M6: erythroleukemia
14
Q
AML M7
A
PAS, AP, NSE+/- (mostly +ANA esterase, -ANB esterase)
M7: megakaryoblastic
