Unit #5B – Clinical
Laboratory Testing
Basic Hematology
Cecile Sanders, M.Ed., MLS(ASCP)
Unit #5B – Clinical Laboratory
Testing – Basic Hematology
 Department
of Hematology
– Study of formed elements of blood and
blood forming tissues
– Screen, diagnosis and monitor hematologic
diseases (anemias, leukemias, etc.) and also
give a general idea of overall health
Unit #5B – Clinical Laboratory
Testing – Basic Hematology

Composition of Blood - blood is 6-8% of total
body weight and equals approximately 5 liters
(think about 5 liter bottles of Coke)
– Serum vs Plasma –
 Both
are fluid portions of blood
 Serum is from clotted blood, has no clotting factors
(used up in the clotting process)
 Plasma is from anticoagulated blood, has clotting
factors, makes up about 45-60% of blood’s volume
Unit #5B – Clinical Laboratory
Testing – Basic Hematology
– Cellular Elements – make up the remainder
of the blood volume
 Erythrocytes
/ RBCs
– ~ 4-6 million/µL
– Transport oxygen and carbon dioxide
Electron Micrograph
Stained Blood Smear Viewed by Microscope
Unit #5B – Clinical Laboratory
Testing – Basic Hematology
 Leukocytes
/ WBCs
– ~ 4,800-10,800 /µL in circulating blood; many more in
tissues
– Function in immunity and defense against bacteria,
viruses and all other foreign materials (includes
allergens like pollen, etc.)
Illustration of WBC
Stained WBC Viewed Under
Microscope
Unit #5B – Clinical Laboratory
Testing – Basic Hematology
– Types of WBCs:
 Granulocytes (neutrophils, basophils, &
eosinophils)
Drawing
Stained Granulocytes Viewed Under
Microscope
Unit #5B – Clinical Laboratory
Testing – Basic Hematology
 Lymphocytes
 Monocytes
(On blood smear)
(On blood smear)
Unit #5B – Clinical Laboratory
Testing – Basic Hematology
 Platelets
/ Thrombocytes
– Pieces of a bone marrow cell known as a
megakaryocyte
– Function to stop bleeding by forming a plug and also
release coagulation factors
Platelets on blood smear (very small “dots” among RBC)
Unit #5B – Clinical Laboratory
Testing – Basic Hematology
 Common
Hematology Laboratory Tests
– Complete Blood Count (CBC) includes:
 RBC
count
 WBC count
 Hemoglobin
 Hematocrit
 WBC Differential
 Platelet count
 Additional information on size and appearance
of blood cells
Unit #5B – Clinical Laboratory
Testing – Basic Hematology
 Common
–
–
–
–
Hematology Laboratory Tests
Erythrocyte Sedimentation Rate (ESR)
Reticulocyte Count
Sickle Cell Testing
Coagulation Tests include:
 Prothrombin
Time (PT)
 Partial Thromboplastin Time (PTT)
 Fibrinogen
 Factor Analysis
Unit #5B – Clinical Laboratory
Testing – Basic Hematology

Hematological Diseases
than one category)
(Diseases may be classified in more
– Diseases of improper or insufficient production
 Anemias
– Examples include iron deficiency anemia
and aplastic anemia, among others
 Leukemias – WBC production is affected and
defective. Examples include acute and chronic
leukemias
 Thrombocytopenia – Decreased platelets. Patient
may have bleeding problems
Unit #5B – Clinical Laboratory
Testing – Basic Hematology
– Diseases of defective cell function
 May
be combination of improper cell production and
defective function
 Examples include iron deficiency anemia and certain
leukemias
– Inherited hematological diseases
 Examples
include hemophilia, sickle cell anemia, G6PD
deficiency, thalassemias
– Secondary or acquired hematological diseases
 Examples
include hemolytic disease due to renal
pathologies or atypical lymphocytes due to viral infections
Unit #5B – Clinical Laboratory
Testing – Basic Hematology
 Resources
– Basic Clinical Laboratory Techniques,
Estridge and Reynolds, Thomson/Delmar
Learning, Fifth Edition, 2008