1 / 71

Diagnostic Laboratory Blood Tests

Diagnostic Laboratory Blood Tests. Complete Blood Count and Blood Chemistry Profiles. Blood Counts. Complete Blood Count. Evaluations of cellular parameters Types of cells Numbers of cells Size and volume of cells. CBC.

fay
Download Presentation

Diagnostic Laboratory Blood Tests

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Diagnostic Laboratory Blood Tests Complete Blood Count and Blood Chemistry Profiles

  2. Blood Counts

  3. Complete Blood Count • Evaluations of cellular parameters • Types of cells • Numbers of cells • Size and volume of cells

  4. CBC • Provides a “snap shot “ of the hematopoietic system at a specific point in time.

  5. White blood cell count Differential count Red blood cell count Hematocrit Hemoglobin Mean corpuscular volume Mean corpuscular hemoglobin Mean corpuscular hemoglobin concentration CBC Components

  6. White Blood Count (WBC) • White blood cells (leukocytes) are the disease fighting cells of the immune system. • Only about 1% of blood cells are WBCs • Large numbers of WBCs can be produced rapidly if needed

  7. White Blood Count (WBC) • The WBC tells the total number of white cells present in a specified volume of blood • Different disease states affect the WBC in different ways

  8. WBC Methods • Hemocytometer • Automated cell counters • Quantitative Buffy Coat Analysis

  9. Manual Hemocytometer • Manual counting is the oldest and most time consuming method of determining cell counts • Special slides and diluting fluids are required • Method can be used for counting cells in other body fluids and effusions

  10. Advantages of Manual Counts • Manual counting is the least expensive in terms of equipment and supplies • Can be performed in a mobile clinic

  11. Limitations of Manual Counts • Time consuming (staff expense) • Inherent error (20%), even with skilled staff • Requires well trained and meticulous personnel

  12. Manual Counts • WBC count is the most frequently performed hemocytometer count • RBC counts are very inaccurate • Meticulous attention to detail is necessary to achieve consistent cell count results when using manual methods

  13. Hemocytometer

  14. Automated Cell Counter • Several types now available for use in vet settings • All types are more accurate than manual methods • Results are obtained rapidly

  15. Types • Semi-automated requires some sample preparation by technical staff • Fully automated performs all steps itself

  16. Automated Cell Counter

  17. Impedance methods • All make use of Coulter principle

  18. Advantages • Faster and more effective use of staff time • Newer models store calibrations for multiple species • Can perform most of components of a complete blood count

  19. Limitations • Cannot perform differential counts • Cannot recognize reticulocytes • Cannot reliably differentiate between WBCs and nucleated RBCs • Several artifacts can create false counts

  20. Quantitative Buffy Coat Analysis • QBC is based on differential centrifugation • Uses special tubes that contain a float that has the same density as the buffy coat • When spun under high speed, the buffy coat components are separated out by density (weight) • Automated reader scans buffy coat and records percentages of aggregates

  21. Advantages of QBC Analysis • Efficient and economical method • Simple to operate • Good for rapid screening in office • The system flags abnormal or unexpected results

  22. Limitations of QBC Analysis • Cannot produce a complete differential count • Cannot distinguish between lymphocytes and monocytes • Does not distinguish between segs and bands

  23. Increased WBCs • Bacterial infections generally increase the numbers of white cells present • Pyometra • Bacterial pneumonia • Peritonitis

  24. Decreased WBCs • Viral infections tend to reduce numbers of WBCs • Parvovirus • Canine Distemper • Feline panleukopenia

  25. Decreased WBCs • Immune system inadequacy • Bone marrow disease • Overwhelming bacterial infection

  26. Differential Counts • Important in order to interpret the WBC results • Gives much of the information needed to interpret WBCs • To date, no machine is able to perform this task adequately and completely

  27. Red Blood Cell Count • The measurement of RBCs is a way of evaluating the blood’s ability to deliver oxygen to tissues and to carry carbon dioxide away • Changes in the morphology of RBCs can give information about bone marrow function • Some infectious agents or parasites may be seen on the RBC surface

  28. Hematocrit • Measures the percentage of RBCs in the total blood • Can give information about the animal’s state of hydration • May show evidence of RBC destruction in the spleen

  29. Hemoglobin • Hemoglobin is the oxygen carrying protein in the RBC • Low levels of Hgb indicate genetic problems, inadequate iron, inadequate B vitamins • High levels of Hgb may indicate abnormalities such as high iron intake, a toxin, or internal organ malfunction

  30. Mean Corpuscular Volume • MCV • Measures the size of the RBCs

  31. Mean Corpuscular Hemoglobin • MCH • Reflects the average weight of the hemoglobin in the RBCs

  32. Mean Corpuscular Hemoglobin concentration • MCHC • Measures the amount of hemoglobin in a given volume of packed red cells

  33. Blood Chemistry

  34. Blood Chemistry Values • Blood chemistry panels measure a variety of substances dissolved in the plasma of blood • Nutrients • Carrying agents • Catalysts • Waste matter

  35. Blood Chemistry • Substances are present in minute amounts • Each substance contributes to the overall health of the patient • Increases or decreases of chemicals can be good indicators of the patient’s condition • Can give valuable aid in making a diagnosis

  36. Aspartate Aminotransferase • AST • Formerly called serum glutamic oxaloacetic transaminase (SGOT) • Enzyme • Levels increase with liver or severe muscle injury

  37. Alanine Aminotransferase • ALT • Formerly known as serum glutamic pyruvate transaminase • Enzyme • Levels increase in general liver injury

  38. Total Bilirubin • T Bili • Measures the total amount of all bilirubin in the serum • Bilirubin is a pigment released in the destruction of RBCs • Increased levels: • Intravascular hemolysis • Primary liver or bile duct disease

  39. Direct Bilirubin • D Bili • Conjugated bilirubin • Bilirubin that has been combined with other compounds by the liver • Increases levels often associated with primary liver disease

  40. Indirect Bilirubin • I Bili • Unconjugated bilirubin • Bilirubin that has not yet been combined with other substances • Increased levels usually associated with abnormal hemolysis

  41. Alkaline Phosphatase • Alk Phos • Enzyme • Related to bone, liver, bile duct system • Increased levels: • Young, growing animals • Bone disease • Liver disease • Bile duct blockage • Steroids and anticonvulsants

  42. Total Protein • T Prot or TP • Measure both albumin and globulin • Gives very general information • Further division of proteins needed for meaningful interpretation

  43. ALB Major plasma protein Transports substances throughout body Increases: Dehydration Decreases: Reduced production by liver Malnutrition Chronic liver disease Kidney disease Tissue fluid loss from wounds, burns Albumin

  44. Globulin • GLOB • Blood protein • Antibodies • Indicator of immune function

More Related