Hematology and Clinical Chemistry Notes

Hematology

  • Definition: Study of blood cells and their formation.
  • Components of Blood:
    • CBC (Complete Blood Count):
    • RBC (Erythrocytes)
    • WBC (Leukocytes): Granulocytes (Neutrophils, Eosinophils, Basophils) & Agranulocytes (Lymphocytes, Monocytes)
    • Platelets (Thrombocytes)
    • Fluid: Plasma vs Serum

Blood Cells

  • RBC:

    • Round cells, carry O2 with hemoglobin, central pallor indicates lower coloring.

  • WBC Functions:

    • Neutrophils: Most common granulocyte, defense against bacteria.
    • Eosinophils: Elevated in parasitic infections/allergies, take up red stain.
    • Basophils: Rarely found, respond like eosinophils, take up blue stain.
    • Monocytes: Become macrophages, involved in immune regulation, erythrocyte turnover, iron recycling.
    • Lymphocytes:
    • Second most common WBC. T-cells regulate immune response; B-cells produce antibodies.

CBC Parameters (Sample Values)

  • WBC:
    • Granulocyte counts and percentages e.g., Neutrophils: 16.70 x 10^9/L
  • RBC Factors:
    • HGB: 12.1 g/dL, HCT: 34.6%, MCV: 94.6 fL, etc.

Blood Smear Analysis

  • Evaluates differential WBC counts, platelets, and cell morphology.

PCV/TS (Packed Cell Volume/Total Solids)

  • PCV: Normal ranges for dogs/cats: 35-50%.
    • Decreased PCV indicates cell destruction, blood loss, or bone marrow failure.
    • Increased PCV indicates dehydration.
  • TS Measurement: Normal range for plasma proteins: 5.0-8.0 g/dL. Conditions affecting TS include protein loss and dehydration.

Hemostasis

  • Definition: Ability to maintain integrity of blood vessels.
  • Phases:
    • Mechanical phase (platelet change)
    • Chemical phase (coagulation cascade)
    • Testing involves various coagulation assays.

Common Hemostatic Defects

  • Congenital: VWD (von Willebrand disease) in Dobermans.
  • Acquired: Defects from trauma or toxins (e.g., warfarin).

Blood Chemistries

  • Importance: Determines levels of chemicals in blood related to organ function.
  • Examples of tests for specific organs:
    • Liver: ALT, AST, ALP, Bilirubin, GGT
    • Kidney: BUN, Creatinine
    • Pancreas: Amylase, Lipase
  • Associated Diseases: Abnormal results indicate various conditions (e.g., diabetes, liver damage).

Sample Collection for Lab Submissions

  • Must follow structured protocols for proper labeling and packaging of samples for analysis.
  • Use specific tubes and materials (e.g., purple top tube).