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  • 1. CBC --- Interpretations

2. Abstract

  • Interpretation of different parameters reported on modern day analyzers is bit tricky and demand continuous monitoring and on-going learning. In present paper interpretation of different reported parameters has been discussed with approach to diagnosis of various abnormalities.

3. objectives The CBC interpretation are useful in the diagnosis of various types of anemias. It can reflect acute or chronic infection, allergies, and problems with clotting. 4.

  • Component of the CBC:
  • Red Blood Cells (RBCs) Hematocrit (Hct) Hemoglobin (Hgb) Mean Corpuscular Volume (MCV) Mean Corpuscular HemoglobinConcentration (MCHC)
  • - Red cell distribution width (RDW)
  • White Blood Cells (WBCs) Platelet

CBC- complete blood count 5. RBC

  • RBC (varies with altitude):
    • M: 4.7 to 6.1 x10^12 /L
    • F: 4.2 to 5.4 x10^12 /L
  • Biconcave disc shape with diameter
  • of about 8m
  • Function : - transport hemoglobin which carries oxygen from the lung to the tissues
  • -acid base buffer.
  • Life span 100-120 days.

6.

  • Hemoglobin :
    • M: 13.8 to 17.2 gm/dL
    • F: 12.1 to 15.1 gm/dL
  • Hematocrit: ( packed cell volume )
  • It is ratio of the volume of red cell to the volume of whole blood.
    • M: 40.7 to 50.3 %
    • F: 36.1 to 44.3 %

Hemoglobin & Hematocrit 7.

    • MCV =mean corpuscular volumeHCT/RBC count= 80-100fL
      • small = microcytic
      • normal = normocytic
      • large = macrocytic
    • MCHC=mean corpuscular hemoglobin concentration HB/RBC count= 26-34%
      • decreased = hypochromic
      • normal = normochromic

MCV&MCHC 8.

  • MCH (mean corpuscular hemoglobin)
  • HB/HCT = 27-32 pg
  • RDW (red cell distribution width)
  • It is correlates with the degree of anisocytosis
  • _ Normal range from 10-15%

MCH & RDW 9.

  • This important value is needed in the evaluation of any anemia.
  • Normal range 1-2%
  • Retic count goes up with
    • Hemolytic anemia
  • Retic goes down with
    • Nutritional deficiencies
  • _ Diseases of the bone marrow itself

The Reticulocyte Count 10. Definition of Anaemia

  • Decrease in the number of circulating red blood cell mass and there by O 2carrying capacity
  • Most common hematological disorder by far
  • Almost always a secondary disorder
  • As such, critical for all practitioners to knowhow to evaluate / determine its cause / treat

11. First Question

  • The onset of Anaemia
  • Acute versus chronic
  • Clues
    • Hemodynamic stability
    • Previous CBC
    • Overt blood loss

12. Types of Anaemia 13. Screening Tests Anaemia

  • Clinical Signs and symptoms of Anaemia
  • Look for bleeding all possible sites
  • Look for the causes for anemia
  • Routine Hemoglobin examination
  • Cut offmarks for Hb
    • US< 13.5 gWHO< 12.5 g
    • SubcontinentLess than 12 g%

14. Clinical Signs to be looked for

  • Skin / mucosal pallor,
  • Skin dryness,palmar creases
  • Bald tongue, Glossitis
  • Mouth ulcers,Rectal exam
  • Jaundice, Purpura
  • Lymph adenopathy
  • Hepato-splenomegaly
  • Breathlessness
  • Tachycardia, CHF
  • Bleeding,Occult Blood

15. PCV or Hematocrit

  • 57% Plasma
  • 1% Buffy coat WBC
  • 42% Hct (PCV)

16. The Three Basic Measures

  • Measurement Normal Range
  • RBC count 5 million 4 to 6
  • Hemoglobin 15 g% 12 to 17
  • Hematocrit 45 38 to 50
  • A x 3 = B x 3 = C - This is the rule of thumb
  • Check whether this holds good in given results
  • If not -indicates micro or macrocytosis or hypochromia.

17. Causes of Anaemia

  • Decreasedproductionof Red Cells
    • - Hypoproliferative, marrow failure
  • Increased destruction of Red Cells
    • - Hemolysis (decreasedsurvivalof RBC)
  • Loss of Red Cells due to bleeding
    • - Acute / chronic bloodloss(hemorrhagic)

18. Anaemia First Test

  • RETICULOCYTE COUNT %

Normal Less than 2%

  • RBC to be or Apprentice RBC
  • Fragments of nuclear material
  • RNA strands which stain blue

19. Reticulocytes Leishmans Supravital 20. Anaemia Hypoproliferative Hemolytic Retics < 2 Retics > 2 Hb% < 12, Hct < 38% 21. Normal CBC 22. Workup Second Test

  • The next step isWhat is the size of RBC ?
  • MCV indicates the Red cell volume (size)
  • Both the MCH & MCHC tell Hb content of RBC
  • If the Retic count is 2 or less
  • We are dealing with either
    • Hypoproliferative anaemia (lack of raw material)
    • Maturation defect with less production
    • Bone marrow suppression (primary/ secondary)

23. Mean Cell Volume (MCV)

  • RBC volume (rather) is measured by
  • The Mean Cell Volume or MCV and RDW

Microcytic < 80 fl MCV Normocytic Macrocytic 80 -100 fl > 100 fl < 6.5 6.5 - 9 > 9 24. Anaemia Workup - MCV Microcytic MCV Normocytic Macrocytic Iron Deficiency IDA Chronic Infections Thalassemias Hemoglobinopathies Sideroblastic Anemia Chronic disease Early IDA Hemoglobinopathies Primary marrow disorders Combined deficiencies Increased destruction Megaloblastic anemias Liver disease/alcohol Hemoglobinopathies Metabolic disorders Marrow disorders Increased destruction 25. Red cell Distribution Width - RDW NormalPopulation Uniform RDW High Population Double 26. Anaemia Workup - 4 thTest Peripheral Smear Study

  • Are all RBC of the same size ?
  • Are all RBC of the same normal discoid shape ?
  • How is the colour(Hb content) saturation ?
  • Are all the RBC of same colour/ multi coloured ?
  • Are there any RBC inclusions ?
  • Are intra RBC there any hemo-parasites ?
  • Are leucocytes normal in number and D.C ?
  • Is platelet distribution adequate ?

27. IDA -CBC 28. Microcytic Hypochromic - IDA 29. IDA Special Tests Iron related tests Normal IDA Serum Ferritin (pmo /L) 33-270 < 33 TIBC ( g/dL) 300-340 > 400 Serum Iron ( g/dL) 50-150 < 30 Saturation % 30-50 < 10 Bone marrow Iron ++ Absent 30. IDA Summary

  • Microcytic MCV < 80 fl, RBC < 6
  • RDW Widened with low MCV
  • Hypochromic MCH < 27 pg, MCHC < 30%
  • RI < 2
  • Serum ferritin Very low < 30 (p mols/L)
  • TIBC Increased > 400 (g/dL)
  • Serum Iron Very low < 30 (g/dL)
  • BM Fe Stain Absent Fe
  • Response to Fe Rx. Excellent

31. IDA- Some Nuggets

  • Look for occult blood loss 2 days non veg. free
  • Pica and Pagophagia Ice sucking
  • Absorption ofHaem Iron> Fe++> Fe +++
  • Food, Phytates, Ca, Phosphate, antacids absorption
  • Ascorbic acid absorption
  • Oral iron Rx. always is the best,? Carbonyl Fe
  • FeSO 4is the best. Reserve parenteral Rx.
  • Packed cell transfusion in emergency
  • Continue Fe Rx at least 2 months after normal Hb
  • 1 gram in Hb every week can be expected
  • Always supplement protein for the Globin component

32. Microcytic Anaemias MCV < 80 fl Serum Iron TIBC BM Perls stain Iron Def. Anemia 0 Chronic Infection + + Thalassemia N + + + + Hemoglobinopathy N N + + Lead poisoning N N + + Sideroblastic N + + + + 33. Macrocytic Anaemias

  • A.Megaloblastic MacrocyticB12 and Folate
  • B.Non Megaloblastic Macrocytic Anaemias
    • Liver disease/alcohol
    • Hemoglobinopathies
    • Metabolic disorders, Hypothyroidism