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
