ANEMIA. Functions of erythrocytes Transport of respiratory gases Large surface area : volume ratio...
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Transcript of ANEMIA. Functions of erythrocytes Transport of respiratory gases Large surface area : volume ratio...
Functions of erythrocytes
• Transport of respiratory gases
• Large surface area : volume ratio
• Flexible biconcave disc
• Haemoglobin for exchange of gases
• Capable of glycolysis for the source of energy for cell survival
Erythrocyte disorders• Qualitative
• Haemoglobin defect(Anemia, Thalassaemia, sickle cell anemia etc)
• Membrane & enzyme abnormalities(G6PD, eliptocytosis, stomato-ovalocytosis)
• Quantitative• Increased (polycythemia) inherited / acquired
• Decrease (inherited / acquired hypoplasia)
• Bleeding
Anaemia• Reduction in
circulation haemoglobin
• Nutritional deficiency anaemias– Iron deficiency
– B12 & folate deficiency anaemia
– Protein deficiency anaemia
– Scurvy & other element deficiency
Iron anaemiadeficiency
B12 & folate deficiency
Nutritional deficiency anaemiaclinical application
Angular Cheilosis
Koilonychia
Glossitis
Marrow iron storesPlummer-Vinsonsyndrome
Anaemia; Globin chain defects
• Thalassaemias
– Reduced globin chain synthesis
• Alpha and Beta chain synthesis defects
• Haemoglobinopathies
– Abnormal globin chain synthesis
Sickle cell disease
Thalassaemia
Anaemia; Globin chain defects
X-ray appearance ofThalassaemic patient
Hemoglobin electrophoresisfor the diagnosis of thalassaemai
Anaemia; Membrane and enzyme defects
• Membrane defects– Elliptocytosis
– Hemolysis
– Stomato-ovalocytosis– Without haemolysis
• Red cell enzymopathies• G6PD
– Hemolysis after oxidant stress
• Blood loss
Elliptocytosis
G6PD deficiency
Anaemia; Reduced erythroid bone marrow
• Marrow failure• Marrow infiltration
Trephine biopsy
(Aplastic Anemia)
Marrow infiltration Normal trephine
C.B.C
• Haemoglobin - 15±2.5, 14 ±2.5 - g/dl • PCV - 0.47 ±0.07, 0.42 ±0.05 - l/l (%)
– Haematocrit, effective RBC volume - better
• RBC count - 5.5 ±1, 4.8 ± 1 x1012/l• MCHC - Hb/PCV - 30-36 - g/dl
– Hb synthesis within RBC
• MCH - Hb/RBC - 29.5 ± 2.5 pg/l– Average Hb in RBC
• MCV - PCV/RBC 85 ± 8 - fl
ANEMIASymptoms : Pallor Jaundice Fatigue Palpitation Dyspnea Vertigo Peptic ulcer Glossitis Dysphagia etc
Classification of Anemia I. Etiologic Classification 1. Impaired RBC production 2. Excessive destruction 3. Blood loss
II. Morphologic Classification 1. Macrocytic anemia 2. Microcytic hypochromic anemia 3. Normochromic normocytic anemia
III. Kinetic Classification
IV. Physiologic Classification
Impaired RBC Production1. Abnormal bone marrow
1.1 Aplastic anemia 1.2 Myelophthisis : Myelofibrosis, Leukemia, Cancer metastasis
2. Essential factors deficiency
2.1 Deficiency anemia : Fe, Vit. B12, Folic acid, etc 2.2 Anemia in renal disease : Erythropoietin
3. Stimulation factor deficiency
3.1 Anemia in chronic disease 3.2 Anemia in hypopituitarism 3.3 Anemia in hypothyroidism
Excessive Destruction of RBC(cont.)
Hemolytic anemia
1. Intracorpuscular defect
1.1 Membrane : Hereditary spherocytosis
Hereditary ovalocytosis, etc.
1.2 Enzyme : G-6PD deficiency, PK def., etc.
1.3 Hemoglobin : Thalassemia, Hemoglobino- pathies
Excessive Destruction of RBC
2. Extracorpuscular defect
2.1 Mechanical : March hemolytic anemia
MAHA (Microangiopathic HA)
2.2 Chemical/Physical
2.3 Infection : Clostridium tetani
2.4 Antibodies : HTR, SLE
2.5 Hypersplenism
Blood Loss
1. Acute blood loss : Accident, GI bleeding
2. Chronic blood loss : Hypermenorrhea
Parasitic infestation
Macrocytic Anemia MCV > 94 MCHC > 31
1. Megaloblastic dyspoiesis
1.1 Vit. B12 deficiency : Pernicious anemia
1.2 Folic acid deficiency : Nutritional megaloblas-
tic anemia, Sprue, Other malabsorption
1.3 Inborn errors of metabolism : Orotic aciduria, etc.
1.4 Abnormal DNA synthesis : Chemotherapy, Anticonvulsant, Oral contraceptives
Macrocytic Anemia MCV > 94 MCHC > 31
2. Non-Megaloblastic dyspoiesis
2.1 Increased erythropoiesis : Hemolytic anemia response to hemorrhage
2.2 Increased membrane surface area : Hepatic disease, Obstructive jaundice, Post-
splenectomy
2.3 Idiopathic : Hypothyroidism, Hypoplastic and Aplastic anemia
Microcytic Hypochromic Anemia MCV < 80 MCHC < 31
1. Fe deficiency anemia : Chronic blood loss, Inadequate diet, Malabsorption, Increased demand, etc.
2. Abnormal globin synthesis : Thalassemia with or without Hemoglobinopathies
3. Abnormal porphyrin and heme synthesis : Pyridoxine responsive anemia, etc.
4. Other abnormal Fe metabolism :
Normocytic Normochromic Anemia MCV 82 - 92 MCHC > 30
1. Blood loss2. Increased plasma volume : Pregnancy, Overhydration3. Hemolytic anemia : depend on each cause
4. Hypoplastic marrow : Aplastic anemia, RBC aplasia5. Infiltrate BM : Leukemia, Multiple myeloma, Myelofibrosis, etc.6. Abnormal endocrine : Hypothyroidism, Adrenal insufficiency, etc.7. Kidney disease / Liver disease / Cirrhosis
Kinetic Classification of Anemia
1. Insufficient erythropoiesis
Stem cells , Hypoplastic marrow, Infiltrated BM
2. Ineffective erythropoiesis
- Megaloblastic anemia
- Thalassemia
- Sideroblastic anemia
3. Uncompensated hemolytic disease with continued
bleeding
Physiologic Classification of Anemia
1. RPI (Reticulocyte Production Index) < 2
(Ineffective erythropoiesis)
1.1 Hypoproliferative anemia
1.2 Maturation disorder
2. RPI > 3 (Effective erythropoiesis)
2.1 Hemolytic anemia
2.2 Blood loss anemia
Physiologic Classification of Anemia
1. RPI (Reticulocyte Production Index) < 2
(Ineffective erythropoiesis)
1.1 Hypoproliferative anemia
(normocytic normochromic, N/N)
- Hypoplastic anemia - Idiopathic/ Chemical/ Infectious / Drug --> Maturation arrest
- Myelophthisic anemia (Marrow infiltration)
- Refractory anemia (Dysmyelopoietic syndrome)
1.1.1 N/N and normal RDW
a) BM failure
b) Decrease marrow stimulation
- Endocrine disease
- Anemia of chronic disease
- Renal disease
1.1.2 Abnormal RBC morphology & RDW
a) Oval macrocyte :- Refractory dysmyelo- poietic
b) Dacrocytes/ tear drops :- Myelophthisic
Physiologic Class. of Anemia RPI < 2
1.2 Maturation disorder
1.2.1 Microcytic, high RDW a) Siderblastic (Microcytic dimorphic RBC) b) Fe def. (Microcytic hypochromic RBC)
1.2.2 Microcytic, normal RDW a) Heterozygous, thalassemia syndrome
b) Anemia of chronic disease
1.2.3 Macrocytic a) Liver disease b) Folate def. c) Vit. B12 def. d) Hemolytic anemia (Normocyte
polychromasia)
Physiologic Class. of Anemia RPI < 2
Physiologic Classification of Anemia
2. RPI > 3
(Effective erythropoiesis)
2.1 Hemolytic anemia
- Intrinsic hereditary disorder - Extrinsic acquired disorder
2.2 Blood loss
- Acute blood loss
- Chronic blood loss (without treatment --> micro-
cytic, hypochromic anemia)
Evaluation of AnemiaA. Hematologic
1. Hematocrit (VPRC preferred)
2. Hemoglobin concentration
3. RBC indices : MCV, MCH, MCHC
4. Leukocyte count
5. Reticulocyte count
6. Platelet count
7. ESR (Erythrocyte sedimentation rate)
8. Stained blood smear : RBC morphology
Evaluation of AnemiaB. Urine analysis
1. Appearance : Color, pH, Clarity, sp gr 2. Test for protein, Bence Jones protein 3. Bilirubin, Uribilinogen 4. Occult blood 5. Microscopic examination
C. Stool
1. Appearance : Color, consistency 2. Occult blood 3. Examination for ova, parasites
Evaluation of AnemiaD. Serum or Plasma
1. BUN 2. Creatinine, if urea N is abnormal 3. Bilirubin : Direct, indirect 4. Protein 5. SI (Serum iron), TIBC (Total iron binding capacity)
E. Special tests in hematology Hb typing / Ham acid test / Coombs’ test, G-6PD,
Ferritin, Sucrose test, Autohemolysis test, Haptoglobin, etc.