Gilmore - Anaemia
Transcript of Gilmore - Anaemia
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Anaemia
Bill Gilmore
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Normal red cell
Bill Gilmore
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Red Cell Development
• Stem Cells, Haemangioblast, mesenchymalstem cells, haemopoietic stem cell, CFU-GEMM, BFU-E, CFU-E
• Early Erythroblast
• Intermediate erythroblast
• Late erythroblast
• Reticulocyte• Mature red blood cell
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Red Cell Development
• Blasts
– Nuclear:cytoplasmic ratio
large
– Chromatin is fine andmeshy
– Nucleoli present
– Perinuclear halo present
(mitochondria)
– Membrane highly
refractile
– Cytoplasm blue
• Changes
– Nuclear:cytoplasmic ratio
lowers
– Chromatin condenses
– Nucleoli disappear
– Perinuclear halo
disappears
– Membrane become lessrefractile
– Cytoplasm become
haemoglobinised
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The red blood cell
• Biconcave disc
• 7 u in diameter
• Lifespan 120 days
• No nucleus, mitochrondria or other organelles
• Function is to carry O2 from the lungs to the
tissues and CO2 from the tissues to the lungs
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Haemoglobin
• Protein moiety - in normal adult
haemoglobin A; 2 chains and 2
chains• Haem - iron containing protoporphyrin
ring
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Haem SynthesisGlycine + succinyl CoA
- aminolaevulinic acidPorphobilinogen
Hydroxymethylbilane
Uroporphyrinogen III
Coproporphyri
nogen III
Protoporphyrinogen IX
Protoporpgyrin IX
Haem
Ala-synthase
FerrochelataseFe2+
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Globin SynthesisDNA
Hn RNA
AAAA5’ cap
5’ cap
5’ cap AAAA
AAAA
- globin
Splicing
Processing
Translation on cytoplasmic ri
Transcription
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Chromosome 16
Chromosome 11
2 1
G A
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Haemoglobin Function
• Carries gases around the body.
• Can bind O2, CO2, CO, Sulphur ,
Cyanide
• Methaemoglobin (Fe3+)
• Carboxy Hb
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Normal Red cell Metabolism
• Energy comes from Embden-Meyerhof
Glycolyic Pathway
• Produces 2,3 diphosphoglycerate fromLuebering-Rapoport shunt
• Produces reducing power from
glycolysis and from pentose phosphatepathway
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Red Cell Membrane
• Phospholipid Bilayer
• Contains important proteins eg spectrin
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Anaemia
• Normal range for Haemoglobin
– Men 150 (+ 20) g/l
– Women 135 (+ 15) g/l
• Clinically relevant anaemia =
Haemoglobin value below 105g/l
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Aetiology of Anaemia
• Decreased proliferation of new RBCs – Low EPO
– Damage to Bone Marrow
• Impairment of maturation of RBCs – Nutritional deficiency (iron, B12, folate)
– Abnormal haem synthesis
• Loss or destruction of RBCs – Haemorrhage
– Haemolysis
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Hypochromic anaemias
• Nutritional deficiency of iron
• Anaemia of chronic disorders
• Sideroblastic anaemia
• Iron overload
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16/39Copyright ©2002 American Society of Hematology. Copyright restrictions may apply.
Schrier, S. ASH Image Bank 2002;2002:100325
Figure 1. Note the profound central pallor of the hypochromic and microcytic RBC
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The Haematology Laboratory
• General Haematology or Blood Science
• Coagulation
• Blood Bank
• Stem Cell Transplantation
•Specialist Haematology – Flow cytometry
– Molecular haematology
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General Haematology or Blood Science
• Automated Blood Cell Counts
• Reticulocyte Counts
• Platelet counts
• Eosinophil counts
•Blood Cell Morphology
• Blood Science includes automated
analysers for other blood parameters
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Blood Specimens
• Taken by venepuncture (branch of
Healthcare Science - Phlebotomy )
• Without anticoagulant = serum / buffycoat
• With anticoagulant = plasma / cells in
suspension
• Defibrinated blood – blood taken and
fibrin removed by agitation with glass
beads
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Anticoagulants
• Ethylene Diamine Tetra Acetic acid
(EDTA) – chelates Ca2+ ions, powerful,
very small amount required, can beheat treated and dried to a negible
volume.
• Sodium Citrate – Chelates Ca2+ ions,remains in liquid form – used for
coagulation studies
• Sodium Oxalate – as with citrate
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Initial Haematological tests
• Full Blood Picture
• Blood Cell Morphology – differential
white cell count plus microscopialobservations
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Normal Full Blood Picture
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Microcytic Anaemia
• Lowered Hb
• Microcytosis – MCV lowered
• Hypochromasia – MCH lowered
• Morphology
– Confirms microcytosis
– Confirms hypochromasia
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Full Blood Picture –
Micro,Hypo
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Macrocytic (Megaloblastic) Anaemia
• Lowered Hb
• Macrocytosis – MCV and MCH raised
• Lowered WCC and Platelet count
• Morphology
– Confirms macrocytosis
– Confirms low WCC and platelets
– Hypersegmented neutrophils present
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FBC- Megaloblastic
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Haemolytic Anaemia
• Lowered Hb
• May be Macrocytosis – MCV and MCH
raised• Morphology
– Confirms macrocytosis
– Macrocytes are polychromasic (reticulocytes) – May contain nucelated Red blood cells
– May be evidence of red cell damage
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FBC- Haemolytic Anaemia
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Microcytic Anaemia
• Lowered Hb
• Microcytosis – MCV lowered
• Hypochromasia – MCH lowered
• Morphology
– Confirms microcytosis
– Confirms hypochromasia
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Further Investigation of Microcytic,
Hyopchromic blood picture• Serum iron
• Total iron binding capacity
• Serum ferritin
• Transferrin receptor assays – soluble –
useful in the anaemia of chronic disease
• Hb electropheresis – useful for
thalassaemia
• Perls’ Prussian Blue – stain for iron
stores in BM – useful for identif in rin
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Macrocytic (Megaloblastic) Anaemia
• Lowered Hb
• Macrocytosis – MCV and MCH raised
• Lowered WCC and Platelet count
• Morphology
– Confirms macrocytosis
– Confirms low WCC and platelets
– Hypersegmented neutrophils present
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Further investigation of a
megaloblastic anaemia• Serum B12 – microbiological assay,
Euglena gracilis
• Serum and red cell folate – microbiological assay, Lactobacillus
casei
• Alternatively - A host of competitiveprotein binding assays for serum B12
and serum/red cell folate
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Investigation of absorption of
B12• Schilling test – excretion in urine after
feeding 27Co or 58Co labelled B12
following by a wash out of unlabeledvitamin. One isotope can be given alone
the other with Intrinsic Factor.
• Whole body counting – no flushing dose
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Investigation of a probable B12
deficiency• Estimation of intrinsic factor in gastric
juice
• Intrinsic factor antibidies
• Parietal cell antibodies
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Response to treatment (Therapeutic
Trial)• Observe the optimal haematological
response after administration of the
haematinic at day 0• Reticulocyte count rises on days 2 and
3 and reaches a peak between days 6
and 7• Red Cell count rises
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Haemolytic Anaemia
• Lowered Hb
• May be Macrocytosis – MCV and MCH
raised• Morphology
– Confirms macrocytosis
– Macrocytes are polychromasic (reticulocytes) – May contain nucelated Red blood cells
– May be evidence of red cell damage
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Diagnosis of a haemolytic
anaemia• Evidence of increased red cell break
down
– Serum bilirubin – Urobilogen
– Serum haptoglobin
– Haemosiderin – 51Cr red cell life span
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Type of Haemolysis
• Direct antiglobulin test (Direct Coombs)
• Osmotic fragility
• Haemosiderin and Hb in urine
• Plasma Hb
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If an hereditary disease is
suspected• Osmotic Fragility
• Autohaemolysis + glucose
• Red cell instability
• Screening test for G6PDH deficiency• Glycolytic enzyme assays – PK first
• Glutathione
• Electrophersis
• 5HbF
• Sickling• Unstale Hb
• Gel electropheresis for red cell membrane proteins