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Course title: Hematology (1) Course code: MLHE-201 Supervisor: Prof. Dr Magda Sultan Date : 19/ 12 / 2013 . Outcome : The student will know : -The types of hemolytic anemias -The diagnosis of hemolytic anemias - The types of hereditary hemolytic anemias.
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Course title: Hematology (1)Course code: MLHE-201 Supervisor: Prof. Dr Magda SultanDate : 19/ 12 / 2013 Outcome : The student will know : -The types of hemolytic anemias -The diagnosis of hemolytic anemias -The types of hereditary hemolytic anemias. -The diagnosis of hereditary hemolytic anemias -The laboratory tests needed for diagnosis
1-Hemolytic anemia(HA) • HA = decreased levels of red blood cells in circulating blood (anemia) because of their accelerated destruction (hemolysis)
A red blood cell survives 120 days • The spleen (part of the reticulo-endothelial system) is the main organ which removes old and damaged RBCs from the circulation. • Breakdown of RBCs can exceed the rate that the body can make RBCs and so anemia can develop.
HEMOLYTIC ANEMIA • Anemia of increased destruction • Normochromic, normocyticanemia • Shortened RBC survival • Reticulocytosis - Response to increased RBC destruction • Increased indirect bilirubin • Increased LDH
Classification of hemolytic anemias • Causes of hemolytic anemiascan be either: 1 - hereditary (genetic ) 2 - acquired.
Physiologic classification of anemia Hemolytic anemia • Hereditary • Defects of hemoglobin • Thalassaemia, Sickle cell anemia • Defects of the red cell membrane • Hereditary spherocytosis, Hereditary elliptocytosis • Defective red cell metabolism (enzymes) • G6PD deficiency. P K deficiency
Acquired • Immune mediated : Autoimmune, isoimmune, drugs • Microangiopathic: DIC, HUS • Hypersplenism • Miscellaneous: drugs, toxin, infection, burn, chemical
Mechanisms of hemolysis:- intravascular - extravascular
Intravascular hemolysis :Red cell destruction occurs in vascular spacee.geclinical states associated with Intravascular hemolacute hemolytic transfusion reactions severe burns physical trauma bacterial infections
Intravascular hemolysis :- laboratory signs of intravascular hemolysis: tests for hemolysis and aditionally: hemoglobinemia methemalbuminemia hemoglobinuria hemosiderinuria
Extravascular hemolysis :red cells destruction occurs in reticuloendothelial systeme.gscyrestem - clinical states associated with extravascular hemolysis :autoimmune hemolysis delayed hemolytic transfusion reactions hemoglobinopathies hereditary spherocytosis hypersplenism hemolysis with liver disease- laboratory signs of extravascular hemolysis: tests for hemolysis
Signs of hemolytic anemia: Physical • Symptoms of anemia • Jaundice • Pallor • Splenomegaly / hepatosplenomegaly
Laboratory features (1) *Morphology: anemia *Peripheral blood smear microscopy: • **fragments of the red blood cells ("schistocytes") can be present • **some red blood cells may appear smaller and rounder than usual (spherocytes) • **reticulocytes are present in elevated numbers. • Normoblastscan be present.
Bone marrow smear microscopy: * Erytrhroid hyperplasia * The level of unconjugatedbilirubin in the blood is elevated. * The level of lactate dehydrogenase (LDH) in the blood is elevated
Laboratory features (2) *The direct CoombꞋs test is positive, if hemolysis is caused by an immune process. *Increased excretion of urobilinogen in the urine *Increasedstercobilinogen in the stool. *Sometimes abnormal results of the osmotic fragility test
Hereditary Hemolytic anemia • Defects of hemoglobin • Thalassaemia, Sickle cell anemia • Defects of the red cell membrane • Hereditary spherocytosis, Hereditary elliptocytosis • Defective red cell metabolism • G6PD deficiency. P K deficiency
Haemoglobinopathy . • The abnormalities of the gene may result from substitution of single amino acid like sickle cell anaemiaor decrease synthesis of the whole globin chain (thalassaemia)
Sickle cell anaemia • Substitution of glutamic acid by valine The Hb is stable when oxygenated state and become unstable and polymerized on deoxygenated state
Sickle cell anaemia • Polymerization will lead to precipitation of Hb. The cell become deformed (sickle shape) and very sticky leading to vascular occlusion and small infarction to the affected areas. • Short life span of cells leading to chronic anaemia,
The origin of the disease is a small change in the protein hemoglobin The change in cell structure arises from a change in the structure of hemoglobin. A single change in an amino acid causes hemoglobin to aggregate.
Sickle cell anaemia Diagnosis Laboratory: Hb 6-9 g/dl, high retics (5-15%), Normocytic anemia , target or anisocytosis Sickling test Hb electrophoresis Hb S 60-100 in SS Parents sickle trait Hb AS
Hgb Electrophoresis • Amino acids in globin chains have different charges • Separates hemoglobin according to charge • 90% Hgb S, 10% Hgb F, small fraction of Hgb A2
Thalassaemia Means defective synthesis of one or more of the globin chains which form normal hemoglobin. In very severe form this globin is totally absent. The defect may be in alpha chain ( thalassaemia), Beta chain ( thalassaemia) or Delta chain ( thalassaemia)
HEMOGLOBIN • NORMAL ADULT RBC CONSISTS OF 3 FORMS OF Hb: - HbA - 2 α and 2 β globin chains - HbA2 – 2 α and 2 δ globin chains - HbF - 2 α and 2 γ globin chains • THALASSEMIAS α and β
Different forms of thalassemia • Alfa thalassemia • Beta thalasemia: major, minor (trait), intermedia • Delta/Beta thalassemia • Hereditary persistentce of fetal hemoglobin (HPFH)
Beta Thalassaemia Defective chain synthesis Excess chain Precipitation cell membrane damage Circulating Red cell Bone marrow Anaemia Hemolytic Ineffective erythropoiesis Erythropoietin increased blood transfusion Iron absorption Bone marrow expansion Iron overload skeletal changes & hyper metabolism Complication and death
Beta-Thalassemia major laboratory features • Severe anemia • Blood film: anisopoikilocytosis, hypochromia, target cells, basophylic stippling, reticulocytes moderately increased and normoblasts . • Marrow: marked erythroid hyperplasia, increased sideroblasts • Shortened red cell survival • Haemoglobin electrophoresis : • Fetal hemoglobin > 90%, HbA absent, HbA2 low/normal/high
HEREDITARY SPHEROCYTOSIS • Defective or absent spectrin molecule • Leads to loss of RBC membrane, leading to spherocytosis • Decreased deformability of cell • Increased osmotic fragility • Extravascular hemolysis in spleen
Hereditary spherocytosis (HS)Laboratory features - hemolytic anemia- blood smear-microspherocytes - abnormal osmotic fragility test, acidifiedglycerol lysis time - negative direct Coombs test
Glucose 6-Phosphate DehydrogenaseFunctions • Regenerates NADPH, allowing regeneration of glutathione • Protects against oxidative stress • Lack of G6PD leads to hemolysis during oxidative stress • Infection • Medications • Fava beans • Oxidative stress leads to Heinz body formation, extravascular hemolysis
G6PD DEFICIENCY • DIAGNOSIS: • QUANTITATIVE ASSAY DETECTING LOW ENZYME • TREATMENT – SUPPORTIVE AND PREVENTATIVE
Assignement : Student name :الشيماء مصطفي عبد العاطي Title:Sickle cell anaemia Student name : اميره اسعد يوسف Title : Haemoglobin electrophoresis . Student name :اميره صلاح مرشدي Title :G6PD deficiency . Student name :انجي عبد الموجود Title : Spherocytic anaemia . Student name : بسمه مهدي رياض Title :Laboratory tests of hemolytic anaemias .
Training questions :What are the tests of hemolysis ? • How to diagnose Sickle cell anaemia ? • How to classify hemolytic anaemias ? • Reference book : • Essential Hematology . • Dacie .