Introduction to Hematology and Anemia

1. Introduction to Hematology and Anemia Download more documents and slide shows on The Medical Post [ www.themedicalpost.net ] Dr. Kalpana Malla MD Pediatrics Manipal Teaching Hospital

2. Blood Blood volume is about 8% of body weight 45 % is formed elements 55% plasma

3. PLASMA 90 % Water 10 % Solutes - Plasma proteins – Albumins(58 %) - maintain osmotic ( oncotic ) pressure Globulins (38 %) - antibodies synthesized by plasma cells Clotting factors – fibrinogen – 4 %

4. FORMED ELEMENTS Three types: Erythrocytes – red blood cells Leukocytes – white blood cells Thrombocytes – platelets – cell fragments

5. Development of hemopoietic system: 3 anatomic stages : Mesoblastic : in extraembryyonic structures - yolk sac (10- 14 days of gestation till 10-12 wks ) Hepatic : liver 6-8wks gestation - 20-24wks-primary site of blood cell production (continues till remainder of gestation) Myeloid : bone marrow (10-12 weeks) Exception : lymphocytes –bone marrow+ other organs

6. Developmental changes : 2 nd to 3 rd trimester: circulating erythrocytes and granulocytes increase 2 nd trimester - Haematocrit levels rise 30-40 % & at term rise is 50-63 % Platelet concentration remains constant from 18 th wks till term Life-span of RBCs ~60- 90 days in newborns vs 120 days

7. Fetal bone marrow space develops - 8 th wk of gestation Neutrophils first observed ~ 5 wks of gestation 14 th wk to term: most common cell found in bone marrow is neutrophil Red marrow: Newborns- in all cavities of bones Older children & adults - in upper shaft of femur, humerus , pelvis, spine, skull and bones of thorax Erythropoiesis : - In- utero controlled by erythroid growth factors produced by monocyte -macrophages of fetal liver - After birth controlled by erythropoietin from kidneys

8. The Red Cell Average life span = 120 days (60-90 days NB) Cleared by RES (spleen, liver primarily) Homeostasis  daily loss = daily production Otherwise  anemia

9. Hemoglobin: Is complex protein - Made up of heme which contains an atom of iron and 4 polypeptide globin chains – reversible transport of Oxygen without expenditure of metabolic energy Oxygen binds to iron in heme (also CO) 23 % of CO 2 is bound to globin portion If there is a problem with any part of the molecule it may not be functional

10. Types of Hb : Embryonic Hb : Gower-1: ζ 2 ε 2 Gower-2: α 2 ε 2 Portland: ζ 2 ץ 2 Fetal Hb : Hb F: α 2 ץ 2 Adult Hb : Hb A : α 2 β 2 Hb A 1 : α 2 δ 2

11. Developmental changes in Hb : 4-8 wks gestation: Gower Hb predominates; disappears by 3 rd month > 8 th wk of gestation- Hb F predominant Hb ~ 24 wks gestation 90 % of total Hb At birth declines to 70 % 6-12 months postnatal life < 2 %

12. Developmental changes in Hb : 16-20 wks gestation- some Hb A detectable 24 th wk gestation: 5-10 % , At term ~ 30 % Hb A present Hb A 2 - < 1 % - At birth - 2-3.4 % At 12 months (normal level) Throughout life ratio of Hb A: Hb A 2 is ~ 30:1

13. Hgb Norms Normal values vary by age and gender High at Birth 20g/dl since HbF has high affinity for oxygen , by 3 months HbA replaces HbF Falls to lower-than-adult values by 3-6 months Rises gradually to adult value by the early teenage years On average, Adult male Hb 2g/dl > female counterpart due to effect of androgen .

14. Hgb and MCV Variability Contemporary Pediatrics, Vol 18, No. 9

15. GRANULOCYTES Neutrophils – phagocytes Eosinophils – red granules, associated with allergic response and parasitic worms Basophils – deep blue granules - Release heparin and histamine

16. Neutrophil

17. Eosinophil

18. Basophil

19. AGRANULOCYTES Granules too small to be visible Monocytes – become macrophages Lymphocytes – B cells and T cells = immune functions

20. Monocyte

21. Lymphocyte

22. Lab Investigation Table: Laboratory Tests in Anemia Diagnosis i . Complete blood count (CBC) A. Red blood cell count 1. Hemoglobin 2. Hematocrit B. Red blood cell indices 1. Mean cell volume (MCV) 2. Mean cell hemoglobin (MCH) 3. Mean cell hemoglobin concentration (MCHC] 4. Red cell distribution width (RDW)C.

23. RBC indices Part of the (CBC) - Mean cell volume (MCV ) – Quantifies a verage red blood cell size Mean cell hemoglobin ( MCH) – Hb amount per red blood cell Mean cell hemoglobin concentration ( MCHC) - The amount of hemoglobin relative to the size of the cell (hemoglobin concentration) per red blood cell

24. Contd - Red Blood Cell Indices Index Normal Value   MCV = 90 ± 8 hematocrit /red cell count ( 80 – 100) femtoliter   (MCH) = 30 ± 3 pg Hb /red cell count (27 - 31) picograms /cell (MCHC)= 33 ± 2 Hb / hematocrit or MCH/MCV   ( 32 – 36) gm/dl

25. Anemias - based on cell size (MCV) and amount of Hgb (MCH) MCV < lower limit of normal: microcytic anemia MCV normal range: normocytic anemia MCV > upper limit of normal: macrocytic anemia MCH < lower limit of normal: hypochromic anemia MCH within normal range: normochromic anemia MCH > upper limit of normal: hyperchromic anemia

26. Mentzer index Calculated number to help differentiate between iron deficiency vs. thalassemia if having microcytic anemia MCV/RBC >13 iron deficiency <13 thal trait

27. Red Cell Volume Distribution Width (RDW) Reflects the variability in cell size Aids in further differentiating between specific etiologies of microcytic , normocytic , and macrocytic RDW = (Standard deviation of MCV ÷ mean MCV) × 100

28. Contd C. White blood cell count 1. Cell differential 2. Nuclear segmentation of neutrophils D. Platelet count

29. Blood smear Assess the size, color, and shape of red cells Look for abnormalities – macrocyte , leptocyte , target cell, Tear drop, Elliptocytosis,burr cell,acanthocyte , Schistocytes,Spherocytosis,Sickle cells,Poikilocytes Anisocytosis , Polychromasia

30. MACROCYTE Larger than normal >8.5 µm diameter

31. LEPTOCYTE Hypochromic cell with a normal diameter and decreased MCV Thalassemia .

32. TARGET CELL Hypochromic with central "target" of hemoglobin. Liver disease, thalassemia, hemoglobin D, postsplenectomy

33. TEAR DROP CELL Drop-shaped erythrocyte, often microcytic. Myelofibrosis and infiltration of marrow with tumor. Thalassemia

34. ELLIPTOCYTE Oval to cigar shaped. Hereditary elliptocytosis, certain anemias (particularly vitamin B-12 and folate deficiency)

35. ECHINOCYTE (BURR CELL) Evenly distributed spicules on surface of RBCs, usually 10-30. Uremia, peptic ulcer, gastric carcinoma, pyruvic kinase deficiency .

36. ACANTHOCYTE Five to 10 spicules of various lengths and at irregular interval on surface of RBCs.

37. STOMATOCYTE Slitlike area of central pallor in erythrocyte. Liver disease, acute alcoholism, malignancies, hereditary stomatocytosis, and artifact

38. SCHISTOCYTE Fragmented helmet- or triangular-shaped RBCs. Microangiopathic anemia, artificial heart valves, uremia, malignant hypertension

39. Microcytic and Hypochromic Smaller than normal ( <7 µm diameter Less hemoglobin in cell. Enlarged area of central pallor.

40. Sickle cell Elongated cell with pointed ends. Hemoglobin S and certain types of hemoglobin C Spherocyte Loss of central pallor, stains more densely, often microcytic . Hereditary spherocytosis and certain acquired hemolytic anemias . poikilocytosis & anisocytosis variation in shape and variation in size

41. Contd II. Reticulocyte count III. Iron supply studies A. Serum iron B. Total iron-binding capacity C. Serum ferritin, marrow iron stain

42. Contd IV. Marrow examination A. Aspirate 1. E/G ratio 2. Cell morphology 3. Iron stain B. Biopsy 1. Cellularity 2. Morphology E/G ratio, ratio of erythroid to granulocytic precursors.

43. Reticulocyte Count Reticulocyte production index RPI= Retic ct x Hb ( obsv )/ Hb (normal) x0.5 Indicates whether the BM is appropriately responding to anemia RPI >3 : inc prod = blood loss/ hemolysis RPI <2 : dec prod / ineffective prod

44. CLASSIFICATION INADEQUATE RESPONSE (RPI <2) Hypochromic , microcytic Normocytic normochromic Macrocytic ADEQUATE RESPONSE (RPI >3) Hemolytic anemia Blood loss

45. ANEMIA

46. What is Anemia? Anemia is defined as a reduction of the red blood cell (RBC) volume or hemoglobin concentration below reference level for the age and sex of the individual Hb < - 2SD or 95 th centile for age and sex

47. Anemia Basics All anemias are either due to…. 1. Ineffective RBC production or 2. Accelerated destruction of the RBC

48. By RBC morphology and By Etiological factors responsible for anemia Classification

49. Microcytic hypochromic anemia 1 . I ron deficiency anemia – nutritional, posthemohragic 2. Ineffective Erythropoiesis - Abnormal hemoglobinopathies , Thalassemia syndrome, - Lead poisoning, Cu deficiency, - Pyridoxine responsive -chronic ds - infection, inflammations , renal ds

50. MICROCYTIC TAILS P : T - Thalassemia A - Anemia of chronic disease I - Iron deficiency anemia L - Lead toxicity associated anemia S - Sideroblastic anemia P – Pyridoxine deficiency

51. Megaloblastic Erythropoiesis a) Nutritional - Folate deficiency, B12 deficiency b) Toxic – Treatment with antifolate compound – methotrexate , , and drugs that inhibit DNA replication – zidovudine , phenytoin c) Congenital disorders of DNA synthesis like Orotic aciduria etc. d) Malabsorption - liver ds - normal newborns, reticulocytosis Macrocytic anemia

52. Macrocytic anemia Non - Megaloblastic Erythropoiesis Chronic hemolytic anemia Liver ds Hypothyroidism Diamond blackfan syndrome

53. 1. Impaired cell production (low reticulocyte count ) - aplastic anemia - pure red cell aplasia - physiological anemia of infancy - infections - Systemic diseases like endocrinal, renal and hepatic diseases - bone marrow replacement – leukemia, tumors, starage ds , myelofibrosis , osteopetrosis 2 Hemolytic anemia ( reticulocyte count high) Normocytic , Normochromic anemia

54. DIMORPHIC ANEMIA When two causes of anemia act simultaneously, e.g : macrocytic hypochromic due to hookworm infestation leading to deficiency of both iron and vitamin B12 or folic acid following a blood transfusion

55. ETIOLOGICAL CLASSIFICATION OF ANEMIA Blood loss Acute Chronic Decreased iron assimilation - Nutritional deficiency - Hypoplastic or aplastic anemia - Bone marrow infiltration like leukemia & other malignancies, - Myelodysplastic syndrome - Dyserythropoietic anemia

56. Increased physiologic requirement - Extracorpscular - alloimmune & isoimmune hemolytic anemia, microangiopathic anemias , infections, hypersplenism , - Intracorpsular defect Red cell membranopathy i.e. congenital spherocytosis , elliptocytosis Hemoglobinopathy like HbS , C,D,E etc. Thalassemia syndrome RBC enzymopathies like G6PD deficiency, PK deficiency etc. ETIOLOGICAL CLASSIFICATION OF ANEMIA

57. Differential of Anemia

58. Follow-up Re-check CBC 4-6 weeks (to confirm response) Continue iron 3-4 months (to replace stores) Generally, should not need treatment for more than 5 months unless there are ongoing losses If no improvement on adequate iron therapy, consider evaluating the child for lead poisoning or thalassemia

59. PHYSIOLOGIC ADJUSTMENTS increased cardiac output increased oxygen extraction (increased arteriovenous oxygen difference) shunting of blood flow toward vital organs and tissues the concentration of 2,3-diphosphoglycerate (2,3-DPG) increases within the RBC The resultant “shift to the right” of the oxygen dissociation curve, reducing the affinity of hemoglobin for oxygen, results in more complete transfer of oxygen to the tissues

60. CLINICAL FATURES weakness tachypnea shortness of breath on exertion tachycardia cardiac dilatation congestive heart failure ultimately result from increasingly severe anemia, regardless of its cause.

61. Serum Iron TIBC BM Iron Comment Iron deficiency D I Responsive to iron therapy Chronic inflammation D D ++ Unresponsive to iron therapy Thalassemia major I N ++++ Reticulocytosis and indirect bilirubinemia D/D of microcytic anemia :

62. Thalassemia minor N N ++ Elevation of A of fetal hemoglobin, target cells, and poikilocytosis Lead poisoning N N ++ Basophilic stippling of RBCs Sideroblastic I N ++++ Ring sideroblasts in marrow Serum iron TIBC BM Iron Comment

63. PYROPOIKILOCYTE RBCs w/c are extremely sensitive to heat

64. HEMOLYTIC ANEMIA- INTRACORPUSCULAR Hereditary spherocytosis Hereditary elliptocytosis Hemoglobinopathies Thalassemias Congenital dyserythropoietic anemias Hereditary RBC enzymatic deficiencies Paroxysmal nocturnal hemoglobinuria Severe iron deficiency

65. HEMOLYTIC ANEMIA- EXTRACORPUSCULAR Physical agents: Burns, cold exposure Traumatic: Prosthetic heart valves, graft rejection Chemicals: Drugs and venoms Infectious agents: Malaria, toxoplasmosis, leishmaniasis Hepatic and renal disease Collagen vascular disease Malignancies Transfusion of incompatible blood Hemolytic disease of the newborn Cold hemagglutinin d/s Autoimmune hemolytic anemia Thrombotic thrombocytopenic purpura (TTP) Hemolytic uremic syndrome (HUS) DIC

66. Alterations of Hbs by disease: Gower Hb in few newborns: Trisomy 13/15 Hb Portland: stillborns with homozygous α -thalassemia Elevated HbF (>2 %): β -thalassemia trait homozygous thalassemia Hb SS, Hb SC preterm infants treated with human recombinant EPO others: hemolytic anemias leukemia aplastic anemia

67. Hb A 2 > 3.4 %: β -thalassemia trait megaloblastic anemia Decreased Hb A 2 :IDA α -thalassemia

68. Thank you Download more documents and slide shows on The Medical Post [ www.themedicalpost.net ]