1. MLAB 1415- Hematology Keri Brophy-Martinez
Introduction to Hematology

2. Terms
Hematology
Study of formed cellular blood elements: the white blood cells, red blood cells and platelets
Hemostasis
Arrest of bleeding by the formation of a barrier to blood loss
Maintenance of an adequate number of cells to carry out the functions of the organism
Hematopoiesis
Dynamic formation and development of blood cells, normally in the bone marrow
Process responsible for the replacement of circulating blood cells

3. Functions of the Hematology lab
Confirm a physician’s clinical impression of a possible hematological disorder
Establish a diagnosis or rule out a diagnosis
Detect an unsuspected disorder
Monitor the effects of radiation or chemotherapy

4. Blood Composition Plasma: 55% Constituents of Plasma Water (92%)
Solutes(8%)
Albumins
Globulins
Fibrinogen
Others ( electrolytes, hormones, vitamins, lipids, salts, enzymes and carbohydrates)

5. Functions of Plasma Transport medium for nutrients & metabolites
Immune Defense
Coagulation

6. Blood Composition Cellular Elements Leukocytes: 1%
White Blood Cell= WBC
Granulocytes- fight infection
Lymphocytes- cellular and humoral immunity
Monocytes- phagocytosis of foreign substances and dead or dying cells
Platelets: 1%
Thrombocytes
Help to maintain hemostasis by plugging capillaries and forming clots
Actually a fragment of cytoplasm from megakaryocyte
Erythrocytes: 43%
Red Blood Cell= RBC
Transports oxygen (O2) to tissues and excrete carbon dioxide (CO2) from tissues
RBC’s do not have a nucleus

7. A Erythrocytes (RBCs)
B&H Lymphocytes
C&E Segmented neutrophil
D Eosinophil
F Monocyte
G Platelets
I Neutrophilic band
J Basophil

8. proteins, albumins, globulins, fibrinogen, electrolytes, hormones, nutrients, and respiratory gases
55%
45%

9. Blood Composition
Plasma: liquid portion of blood from an anticoagulated tubes
Serum: liquid portion of blood from a clotted specimen

10. Reference ranges
Differ according to age, race, sex and geographic location
Established by individual facilities in order to account for patient population
Refer to inside covers of textbook to review various reference ranges

11. Overview: Laboratory testing
Complete Blood Count= CBC
Indications: fatigue, weakness, infection, inflammation, bruising, bleeding
Quantifies the white blood cells (WBC), red blood cells (RBC) , hemoglobin, hematocrit and platelets.
Calculates the RBC indices
WBC Differential: enumeration of the types of WBC’s, RBC morphology, platelets I

12. Sample & Storage Requirements
Whole blood, non-hemolized
Avoid clots
Anticoagulant of choice
K2 or K3 EDTA (ethylene diamine tetracetate)
Purpose of the anticoagulant is to prevent clotting of specimen
Storage
Room temperature- up to 1 day
4oC- to preserve sample longer, but may induce cold agglutination

13. Changes in Aging EDTA Samples
Erythrocyte Changes
Neutrophil Changes
Hypochromic
Smudge/basket cells
Schistocytes
Cytoplasm rupture
Elliptocytes
Pyknotic nuclei
Spherocytes
Loss of granulation
Crenated
Cytoplasmic vacuoles
Loss of nuclear shape, chromatin

14. Observations from Aged EDTA

15. Affect of Hemolysis on CBC Parameters
WBC
Probably unaffected
RBC
Falsely low due to RBC lysis and/or RBC fragments not be counted as RBCs
HGB
Reportable- accurate measurement relies on RBCs being completely lysed
HCT
Falsely low- calculated with an invalid MCV and falsely low RBC
MCV
Invalid falsely low or high depending on the degree of hemolysis. May be falsely low if RBC fragments cause smaller pulses to be produced in the RBC aperature or falsely high if fragmented RBCs fall below the RBC threshold and are not counted.
MCH
Invalid- calculated with a falsely low RBC
MCHC
Invalid- calculated with a falsely low HCT
RDW
Falsely high due to RBC fragments increasing the CV of the RBC histogram
PLT
Falsely high due to RBC fragments being incorrectly counted as platelets

16. References
McKenzie, Shirlyn B., and J. Lynne. Williams. "Chapter 21." Introduction. Clinical Laboratory Hematology. Boston: Pearson, Print
Rodak, Bernadette F., Fritsma, George, and Elaine Keohane. "Chapter 35." Myelodysplastic Syndrome. Hematology Clinical Principles and Applications. St. Louis: Elsevier, Print
Teshima, D. Y. (2017, July). EDTA in transit: Degenerative changes in blood cell morphology. MLO, 49(7),