Hematology Notes 2024-2025 PDF

Dr. Rima HAGE HASSAN 2024-2025 I- Blood and hematopoiesis II- Red blood cells characteristics and red blood cell disorders III- Anemias, classification, polycythemia IV- White blood cells, white blood cells disorders V- Hematological malignancies, leukemias and lymphomas VI- Platelets, t...

Dr. Rima HAGE HASSAN 2024-2025 I- Blood and hematopoiesis II- Red blood cells characteristics and red blood cell disorders III- Anemias, classification, polycythemia IV- White blood cells, white blood cells disorders V- Hematological malignancies, leukemias and lymphomas VI- Platelets, thrombopoiesis VII- Hemostasis, platelets disorders VIII- Disorders of clotting factors, Blood transfusion 2 I- Blood and hematopoiesis 1 The blood 2 Bone marrow 3 Spleen 4 Hematopoiesis 3  I- Blood Functions. Caracteristics Transport The blood is a connective tissue - Transporting oxygen and nutrients to the lungs and tissues It constitutes 8% of the body weight - Bringing waste products to the kidneys and liver Normal adult men have about 5L of blood, - Carries hormones, enzymes, vitamins whereas women average closer to four. Protection The blood has two main components—the blood -Forming blood clots to prevent excess blood loss cells (or formed elements)— and the plasma, the -Carrying cells and antibodies that fight infection fluid phase of the blood Regulation 55% Plasma -Regulating body temperature 1% leucocytes and platelets -Maintaining normal tissue’s pH 45% Erythrocytes 4  I- Plasma The liquid component of blood or cells-free blood is called plasma The plasma has a typical yellowish color. The plasma is a mixture of water, sugar, fat, protein, and salts: It consists of 90% water and 10% dry matter The main job of plasma is to transport blood cells throughout the body along with nutrients, waste products, antibodies, clotting proteins, chemical messengers such as hormones (Erythropoietin EPO, Thrombopoietin TPO…) and proteins (Albumin, Fibrinogen … ) that help maintain the body's fluid balance. 5  I- Plasma Plasmatic proteins: a Albumin (60%) : b Globulin (𝜶, 𝜷 𝒆𝒕 𝜸) (36%): c Fibrinogen (4%) : Blood buffer A role in transport (𝛼, 𝛽) and Forms fibrin filaments maintains Ph immunity (𝛾). Regulates osmotic pressure 6  I- Blood cells Erythrocytes (RBC), platelets(thrombocytes) and leucocytes (WBC). Erythrocytes and platelets are not real cells Erythrocytes are deprived of nucleus Platelets are fragments of cells. They survive only few days in blood and do not undergo divisions Blood cells are born from hematopoiesis in bone marrow. All blood cells are derived from a common pluripotent stem cell Blood smear 7  I- Blood Blood appears on the 21st day of embryogenesis, up to 6 weeks the yolk sac and the dorsal part of the aorta (Aorta-gonad-mesonephros) ensure the formation of blood cells. From the 6th week, the precursor cells from the dorsal part of the aorta colonize the liver, the spleen and the bone marrow which will be the places of formation of blood cells in fetal life. After birth, the bone marrow is the only place where blood cells form (hematopoiesis). 8 II- Bone marrow 9  II- Bone marrow Bone marrow is the flexible tissue in the interior of bones. On average, bone marrow constitutes 4% of the total body mass of humans, in an adult weighing 65 kg The hematopoietic component of bone marrow produces approximately 500 billion blood cells per day. Bone marrow is considered as primary lymphoid organ. 10  II- Bone marrow Red marrow Yellow marrow ✓ Found mainly in the flat bones, ✓ Found in the medullary cavity the pelvis, sternum, cranium, ribs, verteb hollow interior of the middle portion rae and scapulae, and in of long bones the cancellous material at the epiphyseal ends of long bones ✓ Composed mostly of fat cells such as the femur and humerus. ✓ Production of RBCs, platelets and most WBC o At birth, all bone marrow is red. ✓ Consists 50% of hematopoietic tissue o With age, more of it is converted to the yellow type, only around half of adult bone marrow is red. 11  II- Bone marrow Cell types that constitute the bone marrow stroma include: Fibroblasts (reticular connective tissue) Macrophages, which contribute especially to RBC production, as they deliver iron for hemoglobin synthesis. Adipocytes (fat cells): local energy sources Osteoblasts (synthesize bone) Osteoclasts (resorb bone) Endothelial cells, which form the sinusoids. 12  II- Bone marrow The marrow is supplied by nutrient arteries, which divide and eventually give rise to venous sinusoids that are lined by endothelial cells and adventitial cells. The frond-like tissue between the sinusoids contains a mixture of fibroblasts, fat cells, mononuclear cells (including lymphocytes and macrophages), and hematopoietic). Hematopoietic cells in the marrow are spatially organized in ways that are crucial for their normal development and function. Stem cells are embedded in a special niche that lies close to blood vessels and osteoblasts lining the bone. 13  III- The spleen o The spleen is secondary lymphoid organ. o It is the largest organ of the lymphatic system. o Its the site of B and T cell proliferation and antibody formation o It is specialized to filter blood much as the lymph nodes filter lymph. o The spleen is very vascular, its size and weight vary. o The spleen is situated between the fundus of the stomach and the diaphragm, located in the left upper quadrant of the abdomen. 14  III- The spleen The two main types of tissues found within the spleen are red and white pulp separated by a marginal zone. Red pulp: A blood filter : removes aged and damaged red blood cells and microorganisms from circulation A storage place for red blood cells Bacteria can be recognized by macrophages in the red pulp and eliminated directly or after being coated with complement proteins (produced by the liver) and immunoglobulins (produced in the white pulp). The elimination of bacteria and viruses by macrophages is very fast and prevents infections White pulp : - The immune component of the spleen - The white pulp consists of splenic nodules of B and T cells, cells presenting the Ag - Ag derived from blood born pathogens are readily presented to T and B lymphocytes in the white pulp, which can differentiate into effector T cells or plasma cells, respectively. 15  III- The spleen Functions: 1.Storage: The spleen acts as a reservoir for several cell lines: thrombocytes (30%) and leukocytes. 2- Cell maturation: Reticulocytes complete their maturation in the spleen. 3- Filtration: Pitting: allows the spleen to get rid of particulate inclusions in red blood cells without destroying them. Howell-Jolly bodies, Heinz bodies are eliminated by this technique. Culling: filters out defective blood cells and to phagocyte circulating bacteria. 4- Immunological: Largest secondary lymphoid organ 16  IV- Hematopoiesis -Hematopoiesis is the process of production, multiplication and specialization of blood cells in the bone marrow. -Hematopoiesis begins with the most basic blood cell, the stem cell (hematopoietic stem cell, HSC) or “pluripotent hematopoietic stem cell”. - Production rate: 10¹³ cells / day of which 2 millions of RBC / second - The maintenance of this production is assured by growth factors. 17 IV- Hematopoiesis 18 Hématologie, Elsevier Masson, 4e édition  IV- Hematopoiesis Pluripotent cells CSH At the origin of the 2 stem cell types : Myeloïd et Lymphoïd. CFU-GEMM, BFU-E, CFU-GM, CFU-E, CFU-MK Can engage in different differentiation pathways Progenitors Morphological characteristics can be distinguished by analyzes (blood smears) Engage in a unique differentiation pathway Precusrors They are known as blasts They are found in blood Mature cells They end usually with “cytes” 19 20  IV- Hematopoiesis Cell growth require: 1) Medullar microenvironment 2) Growth factors 3) Vitamins and oligo-elements Medullar microenvironment: -Contain many types of cells synthesizing and expressing Interleukin ( IL ) and Growth factor ( GF ) -Interaction between different cells, lead to Terminal stage of cells. -Participate in general organization of bone marrow -Give for stem cells an anatomical and inter-cellular condition →assured hematopoiesis. 21  IV- Hematopoiesis Growth factor: - Growth factors are glycoproteins, produced in bone marrow, liver and kidney. - Growth factors regulate hematopoiesis. - Several growth factors, known as colony stimulating factors ( CSFs ), have been identified: Multilineage CSF (IL-3): acts early in hematopoiesis to induce non-lymphoid cell production. EPO ( Erythropoietin ) acts on erythroblasts TPO ( Thrombopoietin ) acts on megakariocyte line Oligoelements and vitamins: - Some acts on the whole cells like : VitB12, folic acid necessary for DNA synthesis and cell division - Others necessary for fabrication of specific protein: Ex: Iron essential for erythropoiesis 22  IV- Hematopoiesis Growth factors: 23  Chap II: Red blood cells characteristics and red blood cell disorders 1 Erythropoesis 2 RBCs components 3 RBCs metabolism 4 RBCs pathologies 24  Red blood cells RBC utilize hemoglobin to transport oxygen from the lungs to all other tissues in the body, and take carbon dioxide back to the lungs to be removed. They live as long as 120 days. In human erythrocytes are devoid of nucleus and have biconcave shape. The RBC are rich in hemoglobin. The normal concentration of RBC is 4 -5,5 millions /mm³ in women or 4,5- 6 millions/mm³ in men. Are highly flexible and deform readily, allowing passage through vessels of the microvasculature. 25  Red blood cells Known for their bright red color, RBC are the most abundant cell in the blood, accounting for about 40-45% of its volume. The cell membrane is composed of proteins and lipids, and this structure provides properties essential for physiological cell function such as deformability and stability while traversing the circulatory system and specifically the capillary network. There are about one billion RBC in two to three drops of blood, and for every 600 RBC, there are about 40 platelets and one WBC. 26  Erythropoiesis o Erythrocytes are continuously produced in the red bone marrow of large bones. o Erythropoiesis is the production of RBC from CFU-GEMM progenitor. o It occurs in erythroblastic islands within the bone marrow. o The entire sequence (from stem cell to erythrocyte) takes approximately one week. o Just before and after leaving the bone marrow, the developing cells are known as reticulocytes o Approximately 2.4 million new erythrocytes are produced per second in a healthy adult. 27 Erythropoiesis 28 H. Han et al. Human Cell (2023) 36:894–907  Erythropoiesis Each pro-erythroblaste can potentially give rise to 16 erythrocytes, but some precursors fail to develop and are phagocytized by bone marrow macrophages. The principal factor regulating erythropoiesis is a hormone called: Erythropoietin (EPO) EPO is secreted by : The kidneys, endothelial cells of the peritubular capillaries in the renal cortex 90% The liver, Kupffer cells and hepatocytes about 10% Erythropoiesis also need Vit B9, B12, Iron and Vit B6 29 EPO: Regulation 30 H.-M. Shih et al., Jfma 2018, 117 EPO: Regulation 31  Iron The total iron store in the body is around 4g, mainly as hemoglobin. The daily requirement is normally around 1mg 32 Iron absorption 33 Intestinal absorption of iron Iron absorption Iron uptake in macrophages 34  Iron metabolism Free iron is toxic and therefore incorporated into hem or bound to protein within the body. Transferrin transports up to two molecules of iron to tissues that have transferrin receptors, ex. The bone marrow. Ferritin is a water-soluble compound, consisting of protein and iron. Hemosiderin is insoluble and consists of aggregates of ferritin that have partially lost their protein component. Hepcidin liver synthesized hormone → regulation of Fe2+ release into the blood by blocking ferroportin 35  Iron overload There is no mechanism for the excretion of excess iron. Consequently, iron overload can occur as a result of: Increased absorption or parenteral administration Increased absorption: This can be either primary or secondary and results from the following: Primary/hereditary hemochromatosis, an autosomal recessive disorder characterized by excessive intestinal absorption of iron. Erythroid hyperplasia secondary to ineffective erythropoiesis or hemolysis (Thalassemia syndromes) Dietary excess (rare) Inappropriate oral therapy. Parenteral administration: Multiple blood transfusion Inappropriate parenteral iron therapy 36  Vit B12 Vit B12 found in animal products (red meat, eggs, fish etc). DNA synthesis 37 Vit B12: absorption 38  Hemoglobin o Hemoglobin= Heme + globin o Hemoglobin is composed of four globin chains (two α and two β chains) o Each chain is associated with a prosthetic heme group, the oxygen-binding site of the molecule. o The hem pocket allows O₂ binding, while protecting the iron atom from oxidation. o Heme is a porphyrin ring with central iron. o To fix O2, iron must be in ferrous state: Fe2+ + O2 → oxyHb 39  Hemoglobin Adult hemoglobin (HbA) contains two α and two β chains, which are arranged as two dimers, written 2(αβ). The other major hem containing protein in humans is myoglobin, which consists of a single chain associated with a hem group. It is found principally in muscle, where it provides an oxygen reserve. Adult Hemoglobin: HbA= α₂β₂ Fetal Hemoglobin: HbF = α₂γ₂ 40  Hemoglobin When Hb binds oxygen, the 𝛽 chains move closer together. In the deoxygenated state, 𝛽 chains move away → fixation of 2,3-bisphosphoglycerate. 41  RBCs structure o The erythrocyte plasma membrane is composed by a specific proteins: o The proteins of the plasma membrane, both integral and peripheral, are o important constituents of the cytoskeleton. o The red cell cytoskeleton: - Maintains cell shape and confers strength to the erythrocyte membrane, allowing the cell to withstand the stresses of the circulation. - Permits flexibility, which is important in erythrocyte circulation. 42  RBCs structure The proteins of the plasma membrane: o Integral proteins: penetrate the lipid layer and are closely associated with it. Band 3 protein is a glycoprotein Glycophorin A, B, C, D are a group of glycoproteins o Peripheral proteins: are loosely attached to the lipid bilayer. Spectrin, -Ankyrin, -Band 4,1 protein, -Actin. 43  RBCs structure Band 3 protein Glycophorins - A glycoprotein homodimer that transports anions - Glycophorins that have three domains: receptor, (Cl-, HCO3-). transmembrane and cytoplasmic - It has binding sites for ankyrin, band 4.1 protein, - Cytoplasmic domain binds cytoskeletal proteins. haemoglobin and glycolytic enzymes. - Receptor domain can bind lectins and influenza virus Band 4.1 protein Ankyrin - Binds spectrin → strengthening the structure - Binds spectrin b-chains and band 3 protein - Binds band 3 protein and glycophorin Actin Spectrin - Binds spectrin chains - Primary structure component of the cytoskeleton - Heterodimers ⍺+β chains associate → tetramers 44  RBCs structure Membrane protein and lipid abnormalities → alter the shape and reduce the deformability of the RBC. Hemolysis, ex: hereditary spherocytosis and elliptocytosis. Elliptocytosis: an autosomal dominant disease characterized by the presence of oval-shaped RBCs. Spherocytosis: an autosomal dominant disease linked to a spectrin anomaly 45 Metabolism of RBC Glucose Glucose-6P Pentoses phosphate Glycolysis Fructose-6P 6P-gluconolactone NADPH,H+ 2 molecules ATP Fructose-1,6-biP 2 molecules NADH,H+ Ribose-5P Enzyme: G6PD Pyruvate Enzyme: Lactate pyruvate kinase Reduced NADH is a coenzyme of methemoglobin reductase, which reduces inactive 46 Hb (Fe3+) to Hb (Fe2+). Hemolysis Principles of ANATOMY & PHYSIOLOGY, 15th edition, Tortora& Derrickson. 47 RBC morphological abnormalities Anisocytosis An increase in the variability of red cell size. Variation in erythrocyte size is now measured by the red cell distribution width (RDW). Always take the RDW into account when interpreting the mean corpuscular volume (MCV). Target Cells Red cells have an area of increased staining which appears in the area of central pallor. Found in: Obstructive liver disease; Severe iron deficiency; Thalassemia; Hemoglobinopathies (S and C); Post splenectomy 48 Microcytosis Microcytic and hypochromic Decrease in the red cell size. Red cells are smaller than ± 7µm in diameter. The nucleus of a small lymphocyte (± 8,µm) is a useful guide to the size of a red cell. Found in: Iron deficiency anemia; Thalassaemia; Lead poisoning Anemia of chronic disease Macrocytosis Increase in the size of a red cell. Red cells are larger than 9µm in diameter. May be round or oval in shape, the diagnostic significance being different. Found in: Folate and B12 deficiencies (oval); Ethanol (round); Liver disease (round) Reticulocytosis (round) 49 Dimorphic Blood Picture Two distinct populations of red cells. The populations may differ in size, shape or hemoglobin content. Found in: Anemic patient after transfusion Iron deficiency patient's taking supplements Combined B12 / folate and iron deficiency Spherocytosis Red cells are more spherical. Lack the central area of pallor on a stained blood film. Found in: Hereditary spherocytosis Immune hemolytic anemia 50 Stomatocytosis Red cells with a central linear slit or stoma. Seen as mouth-shaped form in peripheral smear. Found in: Alcohol excess; Alcoholic liver disease; Hereditary stomatocytosis Hereditary spherocytosis Acanthocytosis Spherical cells with 2 - 20 spicules of unequal length and distributed unevenly over the red cell surface. Found in: Liver disease; Post splenectomy; Anorexia nervosa 51 Tear Drop Cells Red cells shaped like a tear drop or pear Found in: Bone marrow fibrosis; Megaloblastic anemia Iron deficiency; Thalassaemia Rouleaux Formation: Red cell rouleaux Stacks of RBC's resembling a stack of coins. (Stacked cell due to the excess high-molecular-weight proteins in the blood. Found in: Multiple myeloma; Hyperfibrinogenemia; Hyperglobulinemia 52 Red cell-agglutination Irregular clumps of red cells Found in: Cold agglutinins Warm auto immune hemolysis Howell-Jolly Bodies Small round cytoplasmic red cell inclusion with same staining characteristics as nucleus. Found in: Hemolytic anemias Post splenectomy Megaloblastic anemia 53  Schistocytosis Fragmentation of the red cells. Found in: Micro angiopathic hemolytic anemia Mechanical hemolytic anemia Sickle Cells Sickle shaped red cells Found in: Hb-S disease 54 Basophilic stippling Considerable numbers of small basophilic inclusions in red cells. Found in: Thalassaemia; Megaloblastic anemia; Hemolytic anemia; Liver disease Heavy metal poisoning Elliptocytosis The red cells are oval or elliptical in shape. Long axis is twice the short axis. Found in: Hereditary elliptocytosis; Megaloblastic anemia Iron deficiency; Thalassaemia Myelofibrosis 55 Schistocytosis Fragmentation of the red cells. Found in: Micro angiopathic hemolytic anemia Mechanical hemolytic anemia 56  Complete blood count A complete blood count (CBC) is a test panel that gives information about the cells in a patient's blood. Abnormally high or low counts may indicate the presence of many forms of disease. It measures: a- The number of RBC (RBC count) , (The number is given as an absolute number per liter) b- The total amount of hemoglobin (Hb) in the blood g/dl c- The fraction of the blood composed of RBC (Hematocrit = Ht) in % d- Mean corpuscular [Cell] volume (MCV): The average RBC size measured in femtoliters. e- Mean corpuscular hemoglobin (MCH): The average amount of Hb per RBC in picograms f- Mean corpuscular hemoglobin concentration (MCHC): The average concentration of Hb in the cells. g- Red cell Distribution Width (RDW): The variation in cellular volume of the RBC population. 57  Complete blood count Total WBC: All the white cell types are given as a percentage and as an absolute number per liter. Neutrophils: (increased) May indicate bacterial infection. May also be raised in acute viral infections. Eosinophil: Increased in parasitic infections, asthma, or allergic reaction. Basophile: May be increased in bone marrow related conditions such as leukemia or lymphoma. Lymphocytes: Higher with some viral infections, also raised in chronic lymphocytic leukemia (CLL). Can be decreased by HIV infection. Monocytes: May be raised in bacterial infection, tuberculosis, malaria, monocytic leukemia, chronic ulcerative colitis. 58 CBC: reference values adults (15-70 years) 59  Variations in CBC Type of cells Increased Decreased RBC Polycythemia Anemia WBC Leukocytosis Leucopenia Lymphocyte Lymphocytosis Lymphopenia Granulocyte Granulocytosis Granulocytopenia/ Agranulocytosis Neutrophil Neutrophilia Neutropenia Eosinophil Eosinophilia Eosinopenia rarely Basophile Basophilia Basocytopenia Platelets Thrombocytosis Thrombocytopenia 60  Variation in RBCs Anemia Decrease in Hb value Polycythemia Classified based on MCV and MCHC and whether it Increase in Hb value and in RBC number is regenerative (reticulocytes > 120 G/l) or non- regenerative (reticulocytes