Hemolytic Anemia - Part 1 PDF

INSTITUTE OF MEDICAL SCIENCE TECHNOLOGY HEMOLYTIC ANEMIA- PART 1 DR. NORHAIDA CHE AZMI [email protected] 03-87395894 ext:312 Universiti Kuala Lumpur (UniKL) |...

INSTITUTE OF MEDICAL SCIENCE TECHNOLOGY HEMOLYTIC ANEMIA- PART 1 DR. NORHAIDA CHE AZMI [email protected] 03-87395894 ext:312 Universiti Kuala Lumpur (UniKL) | Where Knowledge Is Applied and Dreams Realised  COURSE LEARNING OUTCOME Upon completion of this course students should be able to: Discuss the causes, clinical features, laboratory investigation and management of the 1 disorders for different types of anemia, white blood cell disorders, disorders of hemoglobin and bleeding & coagulation disorders (C4). Analyze and solve cases with hematological findings given to identify the possible 2 condition or disease (C4, A4). Report hematological findings in written form to present case related diseases in class. 3 (A2) HDB 30803 ADVANCED HEMATOLOGY  TOPIC 6- HEMOLYTIC ANEMIA (PART 1) TOPIC OUTLINES: 1. Hemolytic anemia-definition, classification, mechanism, 2. G6PD deficiency & Hereditary spherocytosis- causes/ etiology, clinical features, lab diagnosis, & treatment HDB 30803 ADVANCED HEMATOLOGY  HEMOLYTIC ANEMIA Hemolytic anemia is defined as increase in the rate of red blood cells destruction from the circulation Or premature destruction of red blood cells before their normal life span of 120 days. Under normal conditions, only old RBCs are destroyed in the reticuloendothelial system (RES). Abnormal hemolysis is the process by which the younger RBC are destroyed in large number by the presence of hemolysis agents 1 HDB 30803 ADVANCED HEMATOLOGY  MECHANISM OF HEMOLYTIC ANEMIA Normal RBC destruction occurs after a mean life span of 120 days via 2 mechanisms A) Extravascular (major): B) Intravascular R B C a re re m o ve d (minor): from circulation via the macrophages of hemolysis Reticuloendothelial occurs inside systems(RES)/ the red blood Mononuclear cell vessel. macrophage system- S p l e e n , l i ve r a n d Predominantly lymph node. fragmentation hemolysis Predominantly macrophage- mediated hemolysis 2 HDB 30803 ADVANCED HEMATOLOGY  MECHANISM OF HEMOLYTIC ANEMIA Normal RBC destruction occurs after a mean life span of 120 days via 2 mechanisms B) Intravascular (minor): A) Extravascular (major): Free hemoglobin binds to haptoglobin, and the complex is cleared from the circulation; thus, a The heme group (iron + decrease in haptoglobin can support a diagnosis protoporphyrin). of hemolytic anemia. Protoporphyrin is ultimately Hemoglobin may oxidize and release the heme converted to bilirubin and group that is able to bind to either albumin r e m o v e d i n s t o o l (methemalbumin) or hemopexin (bind and (stercobilinogen) and urine transport heme to the liver) that gives brown color to plasma (ubilinogen). Hemoglobin may be cleared directly by the kidneys resulting in fast clearance of free hemoglobin and reabsorbed in the proximal tubule, where the iron portion is removed and stored in ferritin or hemosiderin. The proximal tubule slough off with the hemosiderin and producing a "brownish" u r i ne color- HEMOSIDERINURIA & HEMOGLOBINURIA 3 HDB 30803 ADVANCED HEMATOLOGY  DIFFERENCES OF INTRA & EXTRAVASCULAR HEMOLYSIS Hemoglobin may oxidize and release the heme group that is able to bind to either albumin (methemalbumin) or hemopexin (bind and transport heme to the liver) *LDH- catalyzes the conversion of pyruvate to lactate. that gives brown color to plasma 4 HDB 30803 ADVANCED HEMATOLOGY  CLASSIFICATION OF HEMOLYTIC ANEMIA According to underlying causes: Inherited and Acquired 1. Hereditary/Inherited: usually results from 2. Acquired: usually results from an extracorpuscular or intrinsic RBC defect environmental changes except PNH in which there is also an intrinsic factor (mutations in the PIGA gene, which encodes phosphatidylinositol glycan class A (PIGA). 5 HDB 30803 ADVANCED HEMATOLOGY  CLASSIFICATION OF HEMOLYTIC ANEMIA According to site of hemolysis: Intra vs extravascular 6 HDB 30803 ADVANCED HEMATOLOGY  INTRAVASCULAR HEMOLYTIC ANEMIA HEREDITARY/ INTRINSIC DEFECTS Red blood cell enzyme abnormality -G6PD Deficiency- 7 HDB 30803 ADVANCED HEMATOLOGY  Glucose-6-Phosphate Dehydrogenase Deficiency (G6PD) Most common red cell enzymopathy Incidence characterized by reduced activity of G6PD Ingestion of oxidative drugs such as in red cells and occurrence of acute primaquine for malaria can cause haemolysis after exposure to oxidant hemolysis in 10% of American black stress. males (during the building of the Panama Canal). G6PD Ingestion of fava beans and oxidative The primary enzyme in the hexose drugs such as quinine and quinidine can monophosphate pathway important in cause haemolysis. RBC metabolism. Favism is found in the Mediterranean Inheritance of G6PD Deficiency area. G6PD gene located on sex chromosome X at q28 locus. Thus, it is X-linked recessive genetic disorder. Hence, more cases are on males. High prevalence in Africa, Mediterranean countries, Middle East and Asia. All individual with favism shows G6PD def. 8 HDB 30803 ADVANCED HEMATOLOGY  Glucose-6-Phosphate Dehydrogenase Deficiency (G6PD) Mechanism: ↓ G6PD enzyme, ↓ NADPH, ↓ GSH → hemolytic anemia ▪ In G6PD deficiency, RBC fail to develop adequate levels of reduced glutathione (GSH) ▪ This result in oxidation and precipitation of hemoglobin within RBC forming Heinz Bodies 9 HDB 30803 ADVANCED HEMATOLOGY  G6PD Deficiency Clinical Features Factors Causing Hemolysis In G6PD Deficient Patient usually, asymptomatic. Infections –severe bacterial infection But when patient is exposed to Drugs – Anti malaria drug (Primaquine) oxidant stress like Antibiotics (sulphur drug, bactrim, drugs, fava bean or infections, septrin and sulphonamide chemicals Chemicals – nitrate, nitrite,naphthalene Fava bean / Broad bean Then, becomes Sudden pallor, jaundice Haemoglobinuria Neonatal jaundice 10 HDB 30803 ADVANCED HEMATOLOGY  G6PD Deficiency PBF - Evidence of hemolysis Schistocytes (fragmented red blood cells). Spherocytes Degmacytes (aka "bite cells") Pyknocytes (Blister cells) Heinz bodies in the red cells (seen immediately following hemolysis) Heinz Bodies Precipitates of denatured haemoglobin in the red cell. (supravital stain) Red cells with these precipitates cannot deform to pass through microcirculation and they will hemolyse. Biochemical analysis Hyperbilirubinaemia (unconjugated bilirubin) Hemoglobinemia Hemoglobinuria methemalbuminemia Heinz bodies 11 HDB 30803 ADVANCED HEMATOLOGY  Laboratory Findings of G6PD Deficiency G6PD screening test : G6PD fluorescent spot test viewed under long-wave ultraviolet light (365nm) Fluorescence Spot Test (Beutler test). Positive (No fluoresence, no reduction of NADP to NADPH) Dye decolorisation method Time of decolorisation is longer (No NADPH to reduce the dye to colourless compound) Direct enzyme assay Low rate or low production of NADPH CareStart™ G6PD Deficiency Screening Test, a Point-of-Care Diagnostic interpretation of the results. Direct enzyme assay: Panel A, no color change for sample with No fluorescence because deficient G6PD enzymatic activity; no NADPH made Panel B, distinct purple color for sample with normal G6PD enzymatic activity. 12 HDB 30803 ADVANCED HEMATOLOGY  Video demo on Fluorescence Spot Test HDB 30803 ADVANCED HEMATOLOGY  Treatments of G6PD deficiency Stop Offending drugs G6PD-deficient babies – phototherapy and exchange transfusion Blood transfusion Underlying infection is treated 13 HDB 30803 ADVANCED HEMATOLOGY HDB 30803 ADVANCED HEMATOLOGY 14  INTRAVASCULAR HEMOLYTIC ANEMIA Acquired conditions/ Extrinsic defect HDB 30803 ADVANCED HEMATOLOGY ADVANCE HEMATOLOGY 15  1.Chemical & Physical Agents Physical agents Burns - heat on red cells causing acanthocytosis or spherocytosis Chemical agents Acanthocytosis Animal toxin-Venoms of snakes and spiders have enzymes that lyse the membrane of RBC Arsenic -cause hemolysis by interacting with sulfhydryl groups of the RBC membrane. Lead – inhibits enzymes of heme synthesis (ALA dehydratase & haem synthase) 16 HDB 30803 ADVANCED HEMATOLOGY  2. Hemolytic anemia - parasitization of RBC (MALARIA) Malaria Laboratory findings mosquito-borne disease caused Normocytic, normochromic by Plasmodium parasites, which anemia are spread to people through Thrombocytopenia the bites of infected female Hb concentration – as low as 5 mosquitoes Anopheles g/dL Clinical features Thick blood smear shows Mild anaemia inclusion body: Recurrent high-grade fever Sporozoites of P. vivax Splenomegaly Sporozoites of P. malariae night sweats and muscle pain Sporozoites of P. falciparum Icterus / jaundice Sporozoites of P. ovale 17 HDB 30803 ADVANCED HEMATOLOGY  Pathogenesis of hemolysis due to malaria 1.Transmission to human (injects sprozoites) 2.sprozoites enter liver and infect hepatocytes. Liver cells rupture and merozoite released 3. intraerythrocytic cycle: The parasites reproduce asexually (gametocytes) in the RBCs, bursting the cells and releasing more parasites to infect more cells. When the female Anopheles mosquito bites an infected human, the parasites enter the mosquito’s body along the human blood it is drinking. Inside mosquito body, the actual deve lo p ment and maturing of the parasite happens. 18 HDB 30803 ADVANCED HEMATOLOGY  Hemolytic anemia - parasitization of RBC (MALARIA) 19 HDB 30803 ADVANCED HEMATOLOGY  Hemolytic anemia - parasitization of RBC (MALARIA) Quinine, quinidine drugs Blood transfusion – severe cases 20 HDB 30803 ADVANCED HEMATOLOGY  EXTRAVASCULAR HEMOLYTIC ANEMIA Red blood cell membrane abnormality -Hereditary Spherocytosis- 21 HDB 30803 ADVANCED HEMATOLOGY  Hereditary spherocytosis (HS) Hereditary spherocytosis A congenital hemolytic disorder caused by mutations in 5 genes (ANK1, SLC4A1, SPTA1, SPTB, & EPB42) that leads to insufficient of membrane skeletal protein (Spectrins , Ankyrin , Band 3 or Protein 4.2) The mutation reduces the surface area of RBC and cells unable to change shape under pressure. cause red blood cells becomes spherocytes and trapped in the spleen. Inheritance: Autosomal dominant (one copy of the altered gene is sufficient to cause the disorder) Occurs in all races but high frequency found in northern european (1 : 5000) 25 22 HDB 30803 ADVANCED HEMATOLOGY  Etiology of HS Cytoskeleton protein deficiencies: Spectrins – most common Ankyrin Band 3 Protein 4.2 Function of cytoskeleton protein To maintain the normal shape of erythrocyte (biconcave disk). Spectrin deficiency causes loss of RBC surface area, which produce spherical RBCs. 26 23 HDB 30803 ADVANCED HEMATOLOGY  Pathogenesis of HS Decrease Reduced membrane deformability Defect of stability and Loss →Trapped and These cells are cytoskeleton of membrane→ destroyed in the osmotically fragile membrane (the lifespan is reduced reduces surface to spleen by 10-20 days as comapred proteins (Spectrins , volume ratio→ phagocytosis to 120 days) Ankyrin ,Band 3,Protein 4.2) formation of (extravascular spherocytes hemolysis) 29 24 HDB 30803 ADVANCED HEMATOLOGY  Clinical Features & Treatment of HS Clinical Features Anemia Jaundice Pigment gallstones are frequent Individuals with high heme turn over are predisposed to bilirubin stones. Pigment gallstones increased bile pigment production Splenomegaly Treatment Splenectomy – surgery to remove spleen 25 HDB 30803 ADVANCED HEMATOLOGY  Lab findings of HS CBC Mild to moderate anemia MCV slightly low MCHC is increased (due to cell dehydration- membrane loss-sphere shape-hemoconcentration) Reticulocytes are usually 5-20%. PBF Shows microspherocytes: densely staining with smaller diameters Polychromasia -reticulocytes (confirm with supravital stain), anisocytosis and poikilocytosis Osmotic fragility test: shift to the right Direct antiglobulin test negative Confirmation test electrophoretic of RBC membrane proteins 29 26 HDB 30803 ADVANCED HEMATOLOGY  OFT is used to measure the resistance of red cells to hemolysis while being exposed to varying levels of dilution/concentration of saline solution to measure the ability of red cells to take up fluid without lysis. Normally, hemolysis begins in 0.48% saline/sodium chloride. No cells hemolysis in solution 0.5% saline and above. Hemolysis is complete at 0.36% saline. When red cells become more fragile (Hereditary spherocytosis, hemolytic anemia), hemolysis may begin at 0.68%. Shift to the right HDB30803 HDB 30803ADVANCED ADVANCEDHEMATOLOGY HEMATOLOGY 27  28 HDD30803 HDB 30803 ADVANCED ADVANCED HEMATOLOGY HEMATOLOGY  Hereditary Elliptocytosis ❖ an autosomal dominant hemolytic anemia characterized by cigar-shaped (elongated) erythrocytes. ❖ α- or β-spectrin m utants leading to defective spectrin formation. ❖ Protein 4.1 deficiency or abnormality 29 HDB 30803 ADVANCED HEMATOLOGY  Q&A 21 HDB 30803 ADVANCED HEMATOLOGY THANK YOU UNIVERSITI KUALA LUMPUR © Copyright of Universiti Teknikal MARA Sdn. Bhd. Not for commercial use. The company shall not be liable for any indir ect, special or consequential damages arising out of or in connection with the use of this presentation and its content.