Bone marrow Flashcards
Advantage of a bone marrow aspirate
-Rapid turnover
-Better cell morphology
-Material for other tests
-Relative quantity of cell types
May not represent all cells
Advantage of core biopsy
-See architecture
-Explains reason for dry tap when no cells are obtained on aspiration
Slower and more difficult to see cell morphology
Collection aspiration location
Sternum in large animals
-Wing of ilium
-Humerus
-Femur
What is essential to interpreting a marrow aspirate
Concurrent CBC findings needs to be the same day submission
Cellularity of marrow sample
Is there enough cells to look at the sample and make identification. Is it representative of the hematopoietic tissue of your pt. Prefer hypercellular sample
Hemic cells percentage
Hemic cells to fat cell ratio is the best indicator of marrow cellularity in an aspirate
Aplastic/Hypoplastic marrow
Slow decrease in hematopoietic cells is balanced by increased fat cells.
Rapid depletion of hematopoietic cells
Lack of stroma due to sinus rupture-> hemorrhage-> collapse of reticular meshwork that must then rebuild and repopulate. Hypocellular with little fat
Hypercellular bone marrow
Very active bone marrow
Megakaryocytes number in marrow
Should be 4-5 per particle and expect more if low platelets
Assess iron storage
Look for hemosiderin. Golden to brown pigment and may appear black in thick areas. Do not see in cats
Myeloid to erythroid ratio
500 cell count and want to look ad see if there is one lineage of cells. Should usually be about 1:1
Mitotic pool of granulocytes (Myeloid cells)
Myeloblasts, promyelocytes, and myelocytes
Should be about 20% of cells
Post mitotic pool of granulocytes (myeloid cells)
Metamyelocytes to segmented cells
Should be about 80% of cells if healthy
Early Proliferative erythroid pool
Rubriblast to rubricyte
10-15% of cells
