16) Bone marrow & cytochemical stains Flashcards
2 BM compartments
- hematopoietic
- vascular
contents of the hematopoietic compartment of BM
- hematopoietic cells
- stroma (support)
- red & yellow marrow
parts of the vascular compartment of the BM
- nutrient artery
- veins
- arterioles
- sinuses
2 parts of BM that may be collected
aspirate
core biopsy
example of needle used for BM
Jamshedi
sites for BM collection
adult—posterior ileac crest
child <2yo—tibia
not a contraindication for BM collection
low platelet
anticoag therapy
aspirate is used for…
- cell morphology, quantity, maturation process
- cytogenetics
- flow cytometry
- molecular studies
- cultures
crush smear made from aspirate
particle smear
push smear made from aspirate
direct smear
made by touching core biopsy to slide
touch prep
obtained from special needle to take out piece of marrow without distorting its arrangement
core biopsy
core biopsy & particle prep used for…
- architecture of BM
- cellularity of BM
——— are counted on 10x BM aspirate
megakaryocytes
RR megakaryocytes
5-10 per 10x
how is differential count different for BM?
- 500-1000 cells counted
- megakaryocytes not counted
if there is no aspirate, use ——– for differential
touch prep
up to ——– of BM is lymphs in children <3yo
1/3
normal M:E ratio
2:1 to 4:1
used for assessing BM cellularity
core biopsy
used for assessing BM iron stores
aspirate
———-% of erythroblasts have Fe specks (sideroblasts)
30-50
BM finding diagnostic for sideroblastic anemia or MDS
ringed sideroblast
cytochemical BM stains must be performed on fresh slides because…
they stain based on enzyme activity
cytochemical stains are helpful in differentiating —————, because there are >20% blasts
acute leukemias
ancillary studies for BM
- flow cytometry
- cytogenetics
- FISH
- molecular genetics
helpful in detecting minimal residual disease (post-tx)
PCR
4 ways to differentiate leukemic blasts
- morphology
- surface markers
- cytogenetics
- cytochemical stains
MPO stain positives
primary granules
- grans (intense)
- monos (weak)
MPO stain negatives
- lymphs
MPO stain used to differentiate…
AML from ALL
sudan black positives
phospholipids
- grans
- monos (weakly)
sudan black negatives
- lymphs
sudan black has the same application as MPO, except…
it can be used with less fresh specimens
other names for chloroacetate esterase stain
specific esterase
naphthol chloroacetate
specific esterase stain positives
- grans
- masts
specific esterase stain negatives or weak positives
- monos
- lymphs
specific esterase used to differentiate…
grans from monos
other names for alpha-naphthyl esterase stain
nonspecific esterase
alpha-naphthyl butyrate
nonspecific esterase stain positives
- monos
- macros
after staining with nonspecific esterase, ————- will inhibit staining in monos
sodium fluoride
nonspecific esterase dot-like positivity in…
- plasma cells
- hairy cells
- T-cells
- megakaryocytes
nonspecific esterase stain negatives
- grans
- most lymphs
nonspecific esterase stain useful in dx of…
myelomonocytic and monocytic leukemia
PAS
periodic acid schiff stain
PAS stain positives
glycogen
- erythroblasts (strong)
- lymphoblasts (blocklike)
- mature grans
PAS stain negatives
- young grans
- mature lymphs
LAP
leukocyte alkaline phosphatase stain
LAP stains the…
secondary granules of maturing neutros
activated neutrophils contain —- LAP, and CML neutrophils contain —— LAP
↑
↓
causes of ↓ LAP
- CML
- PNH
- ITP
normal LAP
13-130
how LAP is graded
100 neutros are graded 1+ to 4+ by how much they stain
TRAP
tartrate-resistant acid phosphatase
T-cell ALL focal positivity
TRAP
explain how TRAP is used to distinguish hairy cells from mast cells
- acid phosphatase stains all cells
- tartrate removes stain, except from hairy cells, masts, and some lymphs (weak)
- toluidine blue does not stain hairy cells, and it does stain masts
tartrate-resistant
hairy cells
masts
some lymphs (weakly)
TdT
terminal deoxynucleotidyl transferase stain
TdT is a…
DNA polymerase found in the nucleus
TdT is a primitive cell marker for distinguishing…
ALL from lymphoma
TdT positives
almost all T-cell ALLs
TdT negatives
lymphomas
TdT is NOT useful for…
distinguishing myeloid from lymphoid
toluidine blue positives
mucopolysaccharides
- basos
- masts
toluidine blue is useful for distinguishing…
masts from hairy cells
reticulin
framework fibers of the BM
reticulin stain is used to assess…
presence of fibrosis
———— is markedly increased in myelofibrosis
reticulin
