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, normocytic anemia Shortened RBC survival Reticulocytosis - Response to

increased RBC destruction Increased indirect bilirubin Increased LDH

Classification of hemolytic anemias

Causes of hemolytic anemias can be either:

1 - hereditary (genetic ) 2 - acquired.

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

Physiologic classification of anemia

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.g eclinical states associated with Intravascular hemol acute 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.g

scyrestem - 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.

Normoblasts can be present.

Bone marrow smear microscopy: * Erytrhroid hyperplasia * The level of unconjugated bilirubin

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

*Increased stercobilinogen 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

. The abnormalities of the gene may result

from substitution of single amino acid like sickle cell anaemia or decrease synthesis of the whole globin chain (thalassaemia)

Haemoglobinopathy

Sickle cell anaemia Substitution of glutamic acid by valine The Hb is stable when oxygenated

state and become unstable and polymerized on deoxygenated state

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,

Sickle cell anaemia

The origin of the disease is a small change in the protein hemoglobinThe change in cell structure arises from a change inthe structure of hemoglobin.

A single change in an amino acid causes hemoglobinto aggregate.

Diagnosis Laboratory:Hb 6-9 g/dl, high retics (5-15%), Normocytic

anemia , target or anisocytosisSickling testHb electrophoresis Hb S 60-100 in

SS Parents sickle trait Hb AS

Sickle cell anaemia

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

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)

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 ThalassaemiaDefective chain synthesis

Excess chain Precipitation

cell membrane damageCirculating Red cell

Anaemia

Bone marrow expansion

skeletal changes & hyper metabolism

Erythropoietin increased

Ineffective erythropoiesis

Bone marrow

blood transfusion

Iron overload

Complication and death

Hemolytic

Iron absorption

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, acidified glycerol lysis time - negative direct Coombs test

G6PD DEFICIENCYFunction of G6PD

G6PD

GSSG 2 GSH

NADPH NADP

2 H2O H2O2

6-PG G6P

Hgb

Sulf-Hgb

Heinz bodies

Hemolysis

InfectionsDrugs

Glucose 6-Phosphate Dehydrogenase

Functions

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 : العاطي عبد مصطفي الشيماء

Title:Sickle cell anaemiaStudent name : يوسف اسعد اميره

Title : Haemoglobin electrophoresis .Student name : مرشدي صالح اميرهTitle :G6PD deficiency .Student name : الموجود عبد انجيTitle : Spherocytic anaemia . Student name : رياض مهدي بسمهTitle :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 .