Baba Phleb

• Hematology


  The study of formed (cellular) elements of the blood

  
• Hematologists


  Professionals involved in the field of hematology
• Blood is a vascular fluid composed of solid (formed elements), liquid, and gases
• Blood is very important in delivering oxygen, providing immunity against infection, and blood clotting

  
• By examining the cells in blood specimen, the MLS can detect disorders such as leukemia, anemia, other blood diseases, infection and monitor their treatment

  
• Components of blood


  • Solid (formed elements)
  • Gas
  • Liquid

  
• Solid (formed elements) of blood

  • RBC
  • WBC
  • Platelets

  
• Gas components of blood

  • Oxygen
  • Carbon dioxide
• Liquid components of blood

  • Plasma
  • Serum

  
• Plasma


  Liquid portion of the unclotted blood, consists of fibrinogen, albumin and globulin

  
• Serum


  Liquid portion of the clotted blood, consists of albumin and globulin, has no fibrinogen

  
• Sample of choice for hematological tests is whole blood (mixture of cells and plasma)

  
• Whole blood specimen is placed in tube with an anticoagulant to prevent clotting of the sample

  
• Anticoagulant of choice for hematological tests

  Ethylene Diamine Tetraacetic Acid (EDTA)
• Immediate inversion of the EDTA tube eight to ten times is critical to prevent clotting
• A complete blood count (CBC) is the primary analysis performed in the hematology section

  
• Parameters tested in Complete Blood Count (CBC)


  • Red blood cell parameters
  • White blood cell parameters
  • Platelet parameters

  
• Red blood cell parameters in CBC

  • RBC count
  • Hemoglobin
  • Hematocrit
  • Red cell indices (MCV, MCH, MCHC, RDW)

  
• Red Blood Cells (Erythrocytes)


  Normal shape: biconcave disc with central pallor, doughnut-shaped

  Normal size: 6 - 8 micrometer (um)

  Main function: distribute oxygen to the body

  
• Red Blood Cell (RBC) count

  Determines the number of red blood cells in circulating blood

  Reference value: 4.2- 6.0 x 10^12 /L (Male), 3.6- 5.6 x 10^12 /L (Female)

  
• Hemoglobin (Hgb)


  Determines the oxygen-carrying capacity of red blood cells (RBC's)

  
• Hemoglobin determination


  Qualitative - copper sulfate method (S.G. 1.053)

  Quantitative - Hemoglobinometer

  Reference value: Males - 130-180 g/L (13.0-18.0 g/dL), Females - 120-160 g/L (12.0-16.0 g/dL)
• Hematocrit (Hct)


  Determines the volume of red blood cells packed by centrifugation (expressed as a percent)

  Also referred to as Packed Cell Volume (PCV)

  Pertains to the ratio of RBC volume to that of whole blood

  
• Hematocrit (Hct)


  Decreased in cases of anemia, Increased in cases of polycythemia vera

  Reference value: Males - 40-55%, Females - 36-48%
• Red Blood Cell (RBC) Indices

  • Mean Corpuscular Volume (MCV)

  Mean Corpuscular Hemoglobin (MCH)

  Mean Corpuscular Hemoglobin Concentration (MCHC)

  
• Mean Corpuscular Volume (MCV)


  Refers to calculations that determine the size of red blood cells

  
• Mean Corpuscular Hemoglobin (MCH)


  Refers to calculations that determine the amount of hemoglobin

  
• Mean Corpuscular Hemoglobin Concentration (MCHC)

  Determines the weight of hemoglobin in a red blood cell and compares it with the size of the cell (expressed as a percentage)

  
• Red cell distribution width (RDW)


  Machine calculated average that determines the differences in the size of red blood cells (expressed as percent)

  Reference value: 11.5 – 14.5 %

  Anisocytosis – variation in size of RBC's

  Poikilocytosis – variation in the shape of RBC's

  
• White Blood Cells (Leukocytes/Leucocytes)


  Usually round / spherical but some possess irregular shape, contains nucleus and granules in the cytoplasm, slightly larger than RBC's

  Main function: Primarily involved in defense mechanisms of the body (immune system) against infection

  
• White Blood Cell (WBC) Count


  Determines the number of white blood cells in circulating blood

  
• General Types of WBC's

  • Granulocytes (Distinct Granules)

  Mononuclear Cells (Not so Distinct Granules)
• Granulocytes


  • Basophils - Bluish black granules

  Eosinophils - Orange red granules (2-3 lobes)

  Neutrophils - Lilac granules (3-5 lobes)
• Mononuclear Cells


  • Lymphocytes - Almost the same size with RBC, round nucleus almost covering the entire cell

  Monocytes - Kidney/bean/horse-shoe nucleus (largest WBC)
• Differential White Blood Cell Count: Neutro- 50-70%, Lympho- 20-40%, Mono- 2-8%, Eosinophil- 1-3%, Basophil- 0-1%

  
• Neutrophil


  Increased in bacterial infection/acute diseases
• Lymphocytes


  Increased in viral infections
• Monocytes


  Increased in cases of chronic infections
• Eosinophil


  Increased in cases of parasitic/infections/allergies
• Basophils


  Increased in cases of leukemia