The complete blood count (cbc)

complete blood count

1. THE COMPLETE BLOOD COUNT (CBC) Prepared by Muhammad Tariq Medical lab scientist Khyber medical university

2. Introduction The human body is primarily made up of water and cells Stationary cells; skin , muscles, bones and organs(heart , lungs, kidneys) Circulating cells move throughout the body by travelling in the blood provide oxygen to all of the stationary cells Help in fight infection, stop bleeding Information about these cells can provide important clues about the overall health of the body.

3. Cont... CBC , is a lab test that provides information about these circulating cells Sample of blood is collected commonly in EDTA tube and sent to the lab This tube contains  EDTA  (ethylene diamine tetra acetic acid), which acts as a potent  anticoagulant  by binding to calcium in the blood A lab instrument then automatically/manually counts the number of each type of circulating cell

4. Conti... A complete blood count is a series of tests used to evaluate the composition and concentration of the various cellular component of the blood. Most informative single investigation Tests consists of 1. Counts of RBC, WBC, Platelets 2. Haemoglobin, haematocrit , and red cell indices 3. Platelet count, mean platelet volume 4. Histogram of RBC, WBC, Platelets

5. CBC test can help To diagnose 1. Anaemia 2. Haemoglobinopathies 3. Bone marrow aplasia 4. Nutritional deficiencies 5. Thrombocytopenia 6. Autoimmune conditions 7. Infections and Parasitemia 8. Malignancies, response to drug, chemotherapy

6. Red blood cells RBC produced in marrow and requires Iron, copper, cobalt Vitamins; especially B12, folic acid Regulated by erythropoietin, thyroid hormone, androgens Life span - 120 days

7. Conti... Biconcave, disk like structure. Have smooth contours Appears to be of the same size as the nucleus of the small lymphocyte. Have no nucleus 1/3 cell is filled with the HAEMOGLOBIN

8. Normal values Newborn 4.1-6.1 million/mm3 Children 3.6-5.5 million/mm3 Adult (M) 4.6-6.0 million/mm3 Adult (F) 4.2-5.0 million/mm3

9. Decreased RBCs Blood loss Trauma Surgery GL bleeding Impaired production Pure red cell aplasia Pernicious anaemia Megaloblastic anaemia Iron deficiency anaemia Thalassemia etc Increased destruction Hereditary spherocytosis Sickle cell anaemia G6PD Autoimmune Haemolytic disease of newborn Mismatch transfusion DIC etc

10. Increased RBCs Polycethemia vera High altitude chronic obstructive pulmonary disease(COPD, emphysema, chronic bronchitis), pulmonary hypertension, Hypoventilation syndrome, poor blood flow to the kidneys

11. Reticulocyte Normal value 0.5% - 1.5%. Hence <2% RBCs are replaced per day Uses To evaluate anaemia Response to treatment of anaemia Note If the disease causing the anaemia is inside the marrow, the reticulocyte count is decreased If the disease causing the anaemia is outside the marrow, the reticulocyte count is increased

12. RBC Indices MCV (mean corpuscular volume) Reference range is 76-96 femto liters , indicator of the average/mean volume of erythrocytes (RBCs) Calculate using the hematocrit and RBC count

13. Significance Increased Decreased Megaloblastic anaemia Haemolytic anaemia with reticulocytosis liver disease Iron deficiency anaemia Thalassemia sideroblastic anaemia lead poisoning

14. MCH (mean corpuscular hemoglobin ) Reference range is 26-34 picograms (pg) indicator of the average weight of hemoglobin in individual RBCs Calculate using the hemoglobin and RBC count

15. Significance Increased in Macrocytic anaemia Decreased in Microcytic Hypochromic anaemia

16. MCHC (mean corpuscular hemoglobin concentration) Reference range is 32-37 g/ dL (SI units 320-370 g/L) The average concentration of hemoglobin in grams per deciliter Calculate using the hemoglobin and hematocrit values

17. Significence Lesser than (<) 32 g/ dL MCHC Indicates hypochromic RBCs, which is seen in iron deficiency and thalassemia . Greater than (>) 37 g/ dL MCHC Indicates a possible error in RBC or hemoglobin measurement, or the presence of spherocytes

18. RDW (RBC distribution width) Reference range 11.5-14.5%. Determined from the RBC histogram Increased proportional to the degree of anisocytosis (variation in size); coefficient of variation of the mean corpuscular volume High RDW : Seen post-transfusion, post-treatment (e.g., iron, B12, or folic acid therapy), idiopathic sideroblastic anemia , in the presence of two concurrent deficiencies (iron and folic acid deficiencies)

19. Hct ( Hematocrit ) Hematocrit is the percentage of RBCs in a given volume of whole blood Males 41-53% Females is 36-46% (SI units 0.36-0.46 L/L) Reference range for hematocrit is age and sex dependent

20. Hgb ( Hemoglobin ): Reference range for males (conventional units) is 13.5-17.5 g/ dL (SI units 135-175 g/L) Reference range for females (conventional units) is 12.0-16.0 g/ dL (SI units 120-160 g/L) Reference range for hemoglobin is age and sex dependent

21. Platelets PLT (Platelets) Reference range (SI units) is 150-450 X 109/L (conventional units 150,000-450,000/^L) Cytoplasmic fragments of large megakaryocyte 2-3 mm in diameter with granules Promotes clot formation 8-20 per oil immersion field

22. Conti... MPV (mean platelet volume ) Average size of the platelets Reference range is 6.8-10.2 fL MPV is analogous to the MCV for erythrocytes

23. Clinical significance Thrombocytopenia Decreased number of platelets (is associated with bleeding) causes include certain rare inherited disorders, leukemia , autoimmune disorders (e.g., rheumatoid arthritis or lupus) and medications Thrombocythemia Increased platelet count less common associated with clotting disorders such as cancers and infections or other medical conditions

24. White blood cells (WBC)

25. Types of WBCS Granulocytes: have specific granules in their cytoplasm Eosinophil Basophil Neutrophil Non-granulocytes ; have no specific granules Lymphocyte Monocyte

26. Neutrophils (45-65% in cirulation ) Polymorphonuclear cells along with esinophils and basophils ( multi lobulated 2-5 lobules) Small purple garnules Most abundant of WBC Highly motile and play role in acute phase of inflammation especially bacterial infections

27. Significance Neutrophilia ( neutrocytosis ) Acute bacterial infection Acute stress Burn, steroid use Leukaemia, RA Neutrophenia Vit b12/ folate deficiency Aplastic anaemia Medications

28. Esinophils Large orange granules and usually bilobed Stain red dye eosin Esionphilia Allergic reaction Par acetic infection Leukemia Autoimmune disoredrs Esinophenia Nutritional deficiency

29. Basophils (<1% in circulation) Large purple black granules They take up basic dye with blue color like mast cell in apearance Basophilia Allergic reaction CML Hodgkin’s disease Oral contraceptive use Basophenia Nutritional deficiency

30. Monocytes (3-10%) Largest of all WBCs Grey cytoplasm with vacuoles Irregular nucleus, linear chromatin Approach three time of RBC diameter Play role in chronic inflammation, viral infections Stored in spleen and very motile What they do Phagocytosis Antigen presentation Cytokines production

31. Lymphocytes (25-45%) Small , round or oval nucleus Clumped chromatin Blue cytoplasm Three types 1. T-Cell(mature in thymus) Helper cell ; help other cell mature, activate and functions through cytokines production Cytotoxic ; destroy cells infected with viruses Memory; remember the antigens of the past infection

32. 2.B-cells(formed in bone marrow) Plasma-produce large amount of antibodies Memory-remember past infection 3.Natural killer cells(NK) Similar role like cytotoxic T-cell, kill virus infected cells and tumour cells

33. signifincence Lymphocytosis ; Viral infections Leukemias Adrenal insufficiency Lymphocytopenia HIV-destroy T-cells Aplastic anaemia