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Red Blood Cell Disorders. DR.Leni Lismayanti , SpPK-K Dept of Clinical Pathology RSHS/FKUP Bandung. Reference book:. Denise M Harmening. Clinical Hematology and Fundamental of Hemostasis. 5th edition. Philadelphia: FA Davis Co, 2009. RBC Structure & Function. - PowerPoint PPT Presentation
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Red Blood Cell Disorders
DR.Leni Lismayanti, SpPK-K
Dept of Clinical Pathology RSHS/FKUP Bandung
Reference book:• Denise M Harmening. Clinical
Hematology and Fundamental of Hemostasis. 5th edition. Philadelphia: FA Davis Co, 2009.
RBC Structure & Function• Areas of RBC metabolism important in
normal RBC survival and function: RBC membrane Hb structure & function RBC metabolic pathway
RBC Membrane• RBC membran proteins:
- Deformability
- Permeability
• RBC membran lipids:
- Phospholipd
- Glycolipid
- cholesterol
RBC membrane
Abnormality That Can Lead to a Change in RBC Morphology
Abnormality RBC Morphology
Cholesterol accumulation in the RBC membrane (liver disease)
Target cells
Abetalipoproteinemia with cholesterol accumulation
Acanthocytes
LCAT deficiency with cholesterol accumulation
Hemolysis with RBC fragmentation
Decreased phosphorylated spectrin or altered spectrin
Bite cells and spherocytes
Hb Structure & Function
Hb synhesis
depends on 3 prs:- Adequate Iron
delivery & supply- Adequate synthesis
of protophorphyrin- Adequate globin
synthesis
Hb function: delivery and release of oxygen to the tissue and facilitation of CO2 excretion.
RBC Metabolic PathwayATP needs for:
• Hb function
• Membrane integrity & deformability
• RBC volume
• Adequate amounts of reduced pyridine nucleotides
• Protection of metabolic enzymes
RBC Senescence & Hemolysis• RBC traveles 200-300 miles during 120
day life span undergo the process of senescence (aging) metabolic & physical changes.
• 1% RBC taken out (removed) from circulation by RES/MPS process:
- Extravascular hemolysis (90%)
- Intravascular hemolysis (5-10%)
Extravascular Hemolysis
Any questions?
RBC Disorders:
1. Numbers:• Decreased (Anemia)• Increased (Polycythemia)
2. Structure and function:• Hemoglobin• RBC membrane• Abnormal erythropoiesis nutritional
RBC disorders morphologic changes
Anemia• Inability of the circulating blood pool to
supply the tissue with adequate oxygen for proper metabolic function.
• Clinically d/ based on: HT, SS, PE, Lab.• Caused by or associated with underlying
disease.• Usually associated with decrease Hb &
Hct (Lab: + RBC count).• Consideration by age, sex and other fact
Classification of Anemia• Based on Hb level:
• Moderate (7-10), severe (<7).
• BM dynamic:
• Hypoproliferative
• Accelerated destruction
• combination
• Clinically (caused):
• RBC indices (normochromic normocytic)
Categories of anemia by causes1. Blood loss
2. Accelerated destruction
3. Nutritional deficiency
4. BM replacement
5. Infection
6. Toxicity
7. Hematopoietic SC arrest/damage
8. Hereditary/acquired defect
9. idiopathic
Significance of Anemia and Compensatory Mechanism
• N: 1% of RBC loss daily BM produce (measured by reticulocyte count 0.5-2.0%).
• Replacement RBC requires:
1. Adequate functioning SC in BM
2. Normal RBC maturation process
3. Ability to release mature RBC from BM
• Proper HB & RBC production requires:
1. Variety of nutritional factors
2. Normal pathway of Bh synthesis
• In severe anemias symptoms of functional impairment of several organs (+).
• Compensatory mechanism increase 2,3-DPG levels
2,3-DPG• Physiologic regulator of:
1. Normal Hb oxygen-carrying capacity
2. Tissue oxygen delivery
• 2,3-DPG (+) Hb more readily released oxygen to tissues depend on: pH & Oxygen level of arterial blood.
• N individual responds to anemia elevated EPO Recombinant EPO Th/ certain anemia.
Lab Tests in Diagnosis of Anemia
• Hb
• Hct
• (RBC Count)
• RBC indices
• Peripheral Blood Smear
• Reticulocyte Count
• BM smear/biopsy
Treatment of anemia: depends on etiology
Polycythemia1. Polycythemia Vera (Myeloproliferative
disorders).
2. Secondary Hypoxic Polycythemia (Secondary Erythrocytosis).
3. Relative Erythrocytosis.
Manifestations PV SE RE
CLINICAL FEATURES
Cyanosis Absent Present Maybe present
Heart/lung disease Absent Present Absent
Splenomegaly Present in 75% Absent Absent
Hepatomegaly Present in 35% Absent Absent
LAB FEATURES
RBC mass Increased Increased Normal
EPO Decreased (rarely N) Increased (rarely N) Normal
Arterial O2 saturation Normal Decreased Normal
WBC count Increased in 80% Normal Normal
Platelet count Increased in 50% Normal Normal
NRBCs poikilocytes Often present Absent Absent
LAP Increased in 70% Normal Normal
BM Hypercell; eryth & myelop ↑; Erythropoiesis ↑ Normal
Megakaryocytes ↑; fibrosis
Serum vit B12 Increased in 75% Normal Normal
Culture studies Autonomous, ery proliferation EPO dep.col.form Not applicable
Any questions?
RBC MorphologyRBC Morphology
Thank You Very Much for Your Attention