8Anemia Defined by measurement of hemoglobin concentration. Manifestations (symptoms) are related to duration and severity of anemiaBody has physiologic responses to chronic anemia such that many patients are asymptomatic until hg < 8 g/dl .Fatigue, pallor, dyspnea, dizziness and dyspnea on exertion
9SignsPallor of mucous membranes (conjunctiva, tongue, palm of the hands).Nails are delicate and break easily.Hair is thin.Rough skin.
10Classifications of Anemias Microcytic, HypochromicMicrocytosis – small cells (MCV <80)Iron deficiencySideroblasticAnemia of chronic diseaseLead poisoningThalassemia trait
11Microcytic, Hypochromic Many RBCs smaller thannucleus of normallymphocytes, increased central pallor.
12Classifications of Anemias NormochromicHereditary SpherocytosisPNHG6PD deficiencyAplastic anemiaAcute blood loss
13Classifications of Anemias MacrocyticVitamin B12 deficiencyFolate deficiencyLiver diseaseDrugsMPD
14Macrocytic RBCs Most RBCs larger than nucleus of normal lymphocytes. increased MCV.
15Macrocytic Anemia Macrocytosis – large cells (MCV >100) Check vitamin B12, RBC folate (why?), fasting homocysteine, and methylmalonic acid (MMA)*HC and MMA are elevated in subclinical B12 and folate deficiency
16IRON DEFICIENCY ANAEMIA. Iron deficiency is the most common cause of anemia in every common country of the world, and it is the most important cause of microcytic hypochromic anaemia.
17Nutritional and metabolic aspects of the iron: Iron in the body is about g.Iron in the Haemoglobin of the RBC represents a greatest percent of body constitutes.Iron presents in the body in two forms:- Ferrittin.- Haemosiderin.
18Causes of iron deficiency anaemia: Chronic blood loss, especially gastrointestinal tract.Increased demands, during pregnancy, infancy, growth, lactation and menstruated women.Malabsorption especially in the cases of gastroectomy and peptic ulcer.Poor diet.
19Clinical features:When IDA is developing, the RE stores (hemosiderin and ferritin) become completely depleted before anemia occurs.At an early stage, no clinical abnormalities.Later, patient may develops general symptoms and signs of anemia.Spoon or ridged nails in severe case of IDA.Dysphagia.
23Characterized by Increase in total body iron Presence of ringed sideroblasts in bone marrowHypochromic anemia.
24Classification Hereditary form Acquired form (more common) Idiopathic – Refractory anemia with ringed sideroblasts(RARS)secondery
25Pathophysiology Disturbances of enzymes regulating heme synthesis Ringed sideroblasts form when non-ferritiniron accumulated in the mitochondria thatcircle the normoblast nucleus
26Hereditary Sideroblastic Anemia Most common form is sex-linked and dueto an abnormal aminolevulinate synthetase enzyme (ALAS)Decreased heme synthesis due to blockin iron utilization perceived by body as increased need for iron associated with increased iron absorption results in iron overload
28Laboratory findings in SA – Peripheral Blood Moderate to severe anemiaTarget cellsBasophilic stippling↑Fe, N to ↓TIBC, ↑% saturation, ↑ ferritinBone marrow:-Erythroid hyperplasia-Ringed sideroblasts in more than 15% of normoblasts.**Lower number of ringed sideroblast in variety of hematological disorders.
30Macrocytic anemia Other causes include: Drug toxicity Hypothyroidism Liver diseaseMyelodysplasiaMPO
31Megaloblastic macrocytosis The smear in a patient with macrocytic anemia is helpful in identification of megaloblastic changes – macrocytes and hypersegmented neutrophils (>5 lobes)DD: B12 deficiency, folate deficiency, drugs that cause abn.DNA synthesis or folate metabolism, liver disease and myelodysplastic syndromesNon-megaloblastic macrocytosis, on smear patients may have large target cells and acanthocytes.
32Folate deficiencyFound in: Fruits (e.g. citrus, melon, bananas), leafy green vegetables.Causes include:MalabsorptionMedicationsMalignancyHemodialysisDiseases/conditions associated with rapid cell turnover such as pregnancy, infancy,….
33Vitamin B12 deficiency Found in : (meat, fish) The body stores large amounts of B12 therefore decreased dietary intake rarely lead to deficiencyMedications to decrease stomach acid can also contribute to B12 deficiency (antacids)Vegetarians can also contribute to B12 deficiencyIn addition to causing anemia, B12 deficiency can lead to a metabolic peripheral=neuropathy and gastrointestinal disorders.
35Diagnosis 3. Laboratory features hyperbilirubinemia elevation of lactate dehrogenase (LDH)serum iron concentration- normal or increased4. Bone marrow smearhypercellularerythroid cell changes (megaloblasts, an abnormally large cell with nuclear- cytoplasmic asynchrony)myeloid cell changes (hypertsegmentation)megakaryocytes are decreased and show abnormal morphology
38Hemolytic Anemia Acquired Classified according to site of RBC destruction and/or whether mediated by immune system:IntravascularExtravascularImmuneNon-immuneCauses: –Transfusion of incompatible bloodAutoimmuneWarm (IgG-mediated) ; most commonCold (IgM-mediated)Prosthetic valvesTTP/HUSDICCancerDrugs
39Haematological findings in HS Anaemia is usual.[Increased mean corpuscular hemoglobin concentration (MCHC)]Reticulocytosis 5-20%Microspherocytes are seen in the blood film. (densely staining with smaller diameters than normal red cells).
40Other investigationsThe classic finding is that the osmotic fragility is increased.Autohaemolysis is increased and corrected by glucose.Direct antiglobulin test is normal
41G6PD deficiencyG6PD functions to reduce nicotinamide adenine dinucleotide phosphate (NADP) while oxidizing glucose-6-phosphate.NADPH is needed for the production of reduced glutathione (GSH) which is important to defend the red cells against oxidant stress.
42Clinical features G6PD deficiency is usually asymptomatic. Neonatal jaundice.Acute haemolytic anaemia in response to oxidant stress: drugs, fava beans or infections.
43Laboratory diagnosis Between crises blood count is normal. The enzyme deficiency is detected byOne of a number of screening tests orBy direct enzyme assay on red cells.During the crisis, the blood film may show contracted and fragmented cells, bite, blister cells, ………Enzyme assay may give a false normal level in the phase of acute haemolysis.
44The blood film shows irregularly contracted cells [deep red arrows] and sometimes hemighosts [deep blue arrow] in which all the hemoglobin appears to have retracted to one side of the erythrocyte
45Polycythemia / Erythrocytosis Abnormal elevation of hemoglobinRule out “relative” polcythemia caused by contraction of plasma volume, e.g. dehydrationPrimaryPolycythemia VeraRBC production independent of EPOEPO level is low / positive JAK-2 is diagnosticUncommonMay be associated with leukocytosis, thrombocytosis, splenomegalyHyperviscosityHeadache, vertigo, visual changes, mental confusionRisk of transformation into acute leukemiaTreatment??SecondaryRBC production in response to increased EPO productionEPO level is usually highVery commonUsual etiology is chronic hypoxia (COPD)**……………. ( ml) to maintain hct 45-50% and treat underlying problem
46Reticulocytes Immature RBCs. Contain residual ribosomal RNA. Reticulum stains blue using a supravital stain (new methylene blue).Counted and expressed as % of total red cells.
47Reticulocyte CountRetic % = # retics per 100 RBCs Corrected retic= % retics x pt. HCT 45
49What are hemoglobinopathies? A group of inherited disorders characterized by structural variations of the Hb molecule. They are Disorders of globin synthesis rather than heme synthesis.These may result from :Synthesis of abnormal HbReduced rate of synthesis of NORMAL α or β globin chainsGenetic defects of Hb are the most common genetic disorders worldwide.
51Sickle cell disease is a group of haemoglobin disorders, in which there is inherence globin abnormality, caused by substitution of valine for glutamic acid in position 6 in the ß chain.
52Hb S is insoluble and forms crystals when exposed to low oxygen tension. Deoxygenated Hb polymerizes into long fibers which may block different areas of the microcirculation or large vessels causing infarcts of various organs.
53Clinical features:- Chronic haemolysis, leads to jaundice and anemia.- Vaso-occlusion of blood vessels leads to pain.- Infarction and infections.
54Laboratory findings: Low Hb. Peripheral blood film shows, sickle cells, target cells and howell-Jolly body appears.Positive Sickling test (screening test).Hb electrophoresis (confirmatory test) :-Hb SS : 80 – 100%- no Hb A- Hb F : 5 – 15%
55Howell-Jolly bodiesThese are basophilic nuclear remnants (clusters of DNA) in circulating erythrocytes.They are usually observed in hemolytic anemia, following splenectomy, and in cases of splenic atrophy.
56The Sickling Test This is a wet preparation. 5 drops of reagent (Sodium dithionite), are added to 1 drop of anticoagulated blood on a slide. Cover glass is put on and sealed with petrollium jelly/parraffin wax mixture.The reagent is a reducing agent.In Hb SS, sickling occur immediately, while it may take 1 hour in Hb S trait.
57Hb S solubility TestThis is done after the Hb electrophoresis to differentiate between some hemoglobins that have the same electrophoretic mobility. (Differentiate Hb D & Hb G from Hb S)Only Hb S precipitate in the reduced state when placed in a high molarity phosphate buffer (as it removes oxyegen from test environment).0.05 ml of blood is added to 1 ml of the buffer and mixed in a test tube. Positive results : presence of Hb S : cloudy solution . Negative results : other Hbs : clear solution .
58Sicle cell traitThis is a benign condition, where there is no anaemia and normal appearance of RBC on the BF. Haematuria is the most common symptom. Care must be taken with anesthesia, pregnancy and at high altitude.
61*There are two alpha genes on each of two chromosome 16 (four genes in the diploid state) *Only 2 beta globin genes, one on each chromosome 11**Excess alpha chains are unstable -precipitates in the cell which bind to cell membrane, causing membrane damage**Excess b chains* High oxygen affinity – poor oxygen transporter* unstable
62Thalassaemias are a heterogeneous group of genetic disorders, which results from a reduced rate of œ (alpha) and ß (beta) chain synthesis.In alpha thalassaemia, there is no or little alpha-chain syntheses.In beta thalassaemia, there is no or little beta-chain syntheses.
641- Major alpha- thalassaemia or Hydrops fetalis or Hemoglobin Barts : four genes deletion, leads to complete suppression in the synthesis of alpha-chain. Alpha chain is important in formation of hemoglobin F in neonate, so in this case the formation of this haemoglobin which is important for fetal life will fail, leading to death in uterus.2- Three genes deletion: leads to moderate to sever microcytic hypochromic anaemia, with splenomegaly. This is known as Hb H disease.3- Two genes deletion: alpha-thalassaemia trait or minor, associated with mild anaemia.4-One gene deletion: silent thalassemia usually asymptomatic.
65Alpha-Thalassemia minor *Two alpha genes either on same or opposite chromosomes are missing*Unaffected globin genes are able to compensate for the affected genes*Mild anemia – significant microcytosis*Normal lifespan*Hb. Electrophoresis is normal.
66Normal Hemoglobin Electrophoresis * Hgb F (N = < 1% after age 1 year)* Hgb A2 (N = 2-3.5%)*Hgb A1 (N= %)
67Causes: deletionTypegenotypeClinical0 deletionNormal/One deletionThal : + heterozygous- /Silent carrier: mild hypochromic microcytic anemiaTwo deletionsThal trait: + homozygous or 0 heterozygous-/---/Minor: mild hypochromic microcytic anemiaThree deletionsHb H disease:0/+ double heterozygous--/-variable severity, but less severe than Beta Thal Majordeletion of all four a globin genesHb Bart’s; - homozygous--/--Hydrops Fetalis:In Utero or early neonatal deathcomplete absence of a globin synthesis
69Classification:ß- Thalassaemia major, very sever.Intermediate ß- thalassaemiaß- Thalassaemia minor or trait.
70Beta-thalassemia Major Sever anaemia (2-3 g/dl)Enlargement of liver and spleen.Expansion of bones, leads to Bone deformities.
71The classification of Beta Thalassemias Causes: one point mutationTypegenotypeClinical0 mutationNormal/Minor point mutationMinor: Trait0 heterozygousOr+ heterozygous/0/+Minimal anemia; no treatment indicatedTwo mutationsIntermediaDouble distinct mutation0/+severe heterozygoteCan be a spectrum; most often do not require chronic transfusionsSevere gene mutationsMajor+ homozygous(double) Or0 homozygous (double)+/+0/0Cooley’s AnemiaHomozygous minor point mutationNeed careful observation and intensive treatment
72Laboratory findings: *Hemoglobin as low as 2-3 g/dl *Markedly microcytic/hypochromic*Marked anisocytosis and poikilocytosis*Basophilic stippling and polychromasia*Hemoglobin electrophoresis –90% Hb F and increased Hb A2*HPLC: confirmatory test
73Of moderate severity (Hb 7-10 g/dl) Of moderate severity (Hb 7-10 g/dl). The patient may show bone deformity, enlarged liver and spleen.Beta-thalassemia intermedia
74ß- Thalassaemia trait (minor): -This is usually symptomless, but mild anaemia may occur.-Normal iron, ferritin, TIBC-Prenatal counseling.(25% risk rate if both partners carry beta thalassemia minor).-Hb. Electrophoresis:4-7 % Hgb A292-95% Hgb A12-6 % Hgb Fß- Thalassaemia trait (minor):