Varsha Narasimhan CBL Group E2 11/29/2010

 glass microscope slide coated with a thin layer of venous blood  stained with a dye, usually Wright’s stain which can display both basophilia and eosinophilia  used to supplement information from automated hematology analyzers (blood cell counters)

 Maxwell Wintrobe’s wedge slide technique: Step 1. Place a small drop of venous blood on a glass microscope slide, using a glass capillary pipette or a wooden applicator stick Step 2. Position a spreader slide at ~30 degree angle and slowly draw it toward the drop of blood. Step 3. Bring spreader slide in contact with the drop of blood so that capillary action draws the blood across the edge of the spreader slide. Step 4. Pull the spreader slide further out, leaving a thin layer of blood behind. Step 6. After drying for about 10 minutes, the slide can be stained manually or placed on an automated slide stainer. The zone of morphology is the area of optimal thickness for LM examination

Features suggestive of  Anemia and/or jaundice  Sickle cell disease  Thrombocytopenia or neutropenia  Lymphoma  Myeloproliferative disease  Disseminated intravascular coagulation  Renal failure  Retinal problems  Some bacterial or parasitic disease  Disseminated nonhematopoietic cancer  General ill health suggestice of mononucelosis or other infection or disease

“several myelocytes and metamyelocytes and left shifted myeloid series, increased platelets of varying sizes and shapes.”

 Normally, blood contains band cells and neutrophils with 2-5 lobes, with <2% myeloid precursors.  In patients with CML, promyelocytes, myelocytes and metamyelocytes proliferate abnormally and are present in larger numbers in the blood and bone marrow.  Thrombocytosis is observed in 30% - 50% of patients in the chronic stage of CML, occasionally at levels higher than 1,000 x 10 9 /L.  Absolute monocytosis is not uncommon, although monocyte percentage is typically low (<3 percent) on CML  The total absolute lymphocyte count is increased (mean: approximately 15 x 10 9 /L) in patients with CML at the time of diagnosis as a result of the balanced increase in T-helper and T- suppressor cells. B lymphocytes are not increased. 4, 5, 6

 Patient is sedated and area around anterior iliac crest is anesthetized and sterilized  Needle is inserted into marrow and aspirate is drawn into syringe ◦ Bloody liquid containing light-colored particles of marrow.5 -1 mm in diameter Aspirate can be mounted for microscopy as is, stained, and/or mixed with EDTA as an anticoagulant and centrifuged to concentrate cells

 For disorders like iron deficiency anemia, thalassemia, and acquired and inherited hemolytic anemia, blood and lab tests may be enough  Marrow biopsy is superior to aspirate in assessing marrow cellularity and diagnosing infiltrative marrow diseases  Marrow aspirate is useful in very specific cases, like suspected megaloblastic anemia as a result of vitamin B 12 or folic acid deficiency, or surveillance followup of leukemia patients in apparent remission.

“hypercellular, with increased M:E ratio. The myeloid series is shifted to the left, with 5% blasts. Megakaryocytes are increased.”

 CML bone marrow is often hypercellular, with bone ; hematopoietic tissue takes up 75 to 90 percent of the marrow volume, with fat markedly reduced  M:E is myeloid to erythroid precursor ratio; granulopoeisis increases. Erythropoeisis also decreases because erythroid precursor maturation is blocked at the basophilic erythroblast stage.  Bone marrow blast levels are 5% or less in the chronic phase of CML  Megakaryocytes are platelet precursors; elevation in bone marrow aspirate is fairly common in CML and is a symptom of thrombocytosis. 8,9

1. topath/pbs.html topath/pbs.html Bain, B. (2005) Diagnosis from the Blood Smear. New England Journal of Medicine 353:17, Cramer, E. “Hematopoeisis.” Lecture. 19 Nov cml/symptoms-of-cml.html cml/symptoms-of-cml.html earchStr=leukemia%2c+myelocytic%2c+chronic earchStr=leukemia%2c+myelocytic%2c+chronic