Section 11: Bone Marrow

Question 1

Identify indications for a bone marrow study

Answer 1

Mostly used to monitor a course of a disease and effectiveness of treatment
but can be used to confirm suspected diagnosis

Question 2

List the most common sites for bone marrow studies in both Adults and Children

Answer 2

Adults - Sternum, Posterior Iliac crest, Anterior iliac crest
Child - leg bone or bone in the spine ? idk this seems f’d up

Question 3

Define Dry Tap and discuss the possible causes of this phenomenon

Answer 3

Dry Tap (failure to obtain any tissues) usually indicates significant disease, often carcinoma, leukemia (hairy cell) etc

Question 4

Describe bone marrow preparations

Answer 4

Aspirate - fresh aspirate smears - small grey marrow spicules
-EDTA specimen for flow cytometry
-Na+ Heparin

Biopsy - touch prep, uses core (preserved for histology tissue sectioning)

Question 5

300 wbc differential and 75 nrbcs were noted
what is the M:E ratio?

Answer 5

M:E ratio = 300:75 or 4:1

Question 6

State the M/E ratio reference range for adults

Answer 6

Reference range: 3:1 to 4:1

Question 7

Define: *Osteoblast and *Osteoclast

Answer 7

Osteoblast - build bone resembles a plasma cell, slightly larger, halo separates nucleus

Osteoclasts - breakdown and recycle, resembles a megakaryocyte, multiple nuclei clearly separated from one another

OsteoBlast (Build) OsteoClast (Catastrophe)

Question 8

Assess the cellularity of a bone marrow specimen. What’s the normal range?

Answer 8

• Use touch prep only
• Done by estimating the ratio of hematopoietic cells to fat, obviously want a good mix.
• Normal range of cellularity - 25-75% hematopoetic tissues

Question 9

State the reference range for a differential done on bone marrow

Answer 9

high PMNs and bands, high lymphs, rubricytes and metarubricytes high

Question 10

discuss how bone marrow iron stores are evaluated, include the stain used and appearance of a normal bone marrow

Answer 10

Iron stains - Prussian Blue
usually 3-6 iron laded nurse cells/IpF
Rbs precursors (20-50% rbc will contain iron gran)

Question 11

Identify a few diseases that are only made by a BM exam

Answer 11

lipid metabolism disorders, MM, tumor metastasis, pancytopenia, aplasia..etc

Question 12

What is the normal fat to hematopoetic tissue in bone Marrow?

Answer 12

50:50

Question 13

Marrow Interpretation: Low Power
Megakaryocyte estimate?
What type of cellularity?

Answer 13

• Meg estimate - 3-6/Ipf (low power field): OHSU 1% wbc
• Cellularity - touch prep
• scan for focal infiltrates

Question 14

Marrow interpretation: Oil immersion
Confirms what?

Answer 14

confirms focal infiltrates

Question 15

Describe Nurse Cells and their roles in BM

Answer 15

Central located macrophage with a ring of maturing erythroid cells (like a lil halo). Provides substances for growth of cells
Also known as an erythroblastic Island

Question 16

Are lymphocytes included in the M:E ratio? What about the differential?

Answer 16

Not in the M:E ratio but used in the diff (duh)

Question 17

Identify the Cell:

Answer 17

Osteoblast

Question 18

Identify the Cell

Answer 18

Osteoclast

Question 19

Identify the Cell

Answer 19

Fat Cells (me)

Question 20

Describe Mast cell function and identification and when it is increased

Answer 20

morphologically similar to blood basophils, different stem cell origin tho

Increased in: chronic infections, AI infections, systemic mastocytosis

Question 21

Identify the Cell

Answer 21

Mast cell, looks just like a baso

Question 22

Define Siderocyte

Answer 22

nonnucleated rbc with Fe granules

Question 23

Define Sideroblast

Answer 23

• nucleated rbc with Fe granules

Question 24

An increase in siderocytes or ringed sideroblasts may indicate _____.

Answer 24

Sideroblastic Anemia

Question 25

Iron Stain: Normal/Increase/Decreased iron in this image?

Answer 25

normal

Question 26

Iron Stain: Normal/Increase/Decreased iron in this image?

Answer 26

decreased/none present

Question 27

Iron Stain: Normal/Increase/Decreased iron in this image?

Answer 27

Increased

Question 28

Identify the Cell type

Answer 28

ringed sideroblasts with prussian blue stain