Eti0logical Classification Of Anemia

OBJECTIVES

Definition

General Presentation

Classification

What is Anemia?

Anemia refers to a state in which the level of hemoglobin in the blood is below the normal range appropriate for that age and sex.

WHO Definition Male less than 13 g/dl Female less than 12 g/dl Pregnant less than 11 g/dl

Factors responsible forAnemic State

Volume lossReduced red cell massReduced hemoglobinRed cell / Hemoglobin defectImpaired red cell / hemoglobin

production

Ultimately, the oxygen-carrying capacity ofblood is reduced.

PALLORSites to look for:

Palpebral conjunctiva Skin Creases of palms and hands Nails Mucous membranes

Presentation

Usually non-specific symptoms:

Tiredness Lightheadedness Breathlessness Lassitude

Non-specific signs:

Pallor Tachypnoea Raised jugular venous pressure Postural hypotension Tachycardia Flow murmurs

Etiological Classification Of Anemia

3 major categories

1) Marrow production defects (Hypoproliferation)

2) Red cell maturation defects (Ineffective erythropoiesis)

3) Decreased red cell survival (Blood loss/Hemolysis)

Hypoproliferative Anemias

Marrow damage:• Infiltration (leukemia,lymphoma) /

fibrosis• Aplasia• Drugs (anti-retrovirals)

Fe def.

Disturbance of proliferation and differentiation of stem cells:

• Pure red cell aplasia

• Anemia of renal failure

• Anemia of endocrine disorders (hypoTH, DM)

Unknown / multiple mechanisms

• Anemia of chronic inflammations

1. Chr. Microbial infections (OM, bac endocarditis, lung abscess)

2. Chr. Immune disorders (RA, regional enteritis)

3. Neoplasms (HL, ca lung/breast)

• Myelophthisic anemias

Maturation Disorders

Cytoplasmic defects:

• Defecient heme synthesis fe def.

• Defective globin synthesis thalassemia

• Myelodysplastic syndromes sideroblastic anemia

Nuclear defects:

• Folate def.

• Vit. B12 def.

• Drug toxicity (mtx, alkylating agents)

• Refractory anemia (myelodysplasia)

Blood loss

Blood loss:

• Acute trauma

• Chronic lesions of g.i.t. gynaecologic disturbance

Hemolytic Anemia

Intrinsic abnormalities of red cells

1. Hereditary

a) Red cell membrane disorders

• Disorders of membrane cytoskeleton:Spherocytosis Elliptocytosis

• Disorders of lipid synthesis:selective increase in membrane

lecithin

b) Red cell enzyme deficiencies

• Glycolytic enzymes:PK def.Hexokinase def.

• Enzymes of HMP shunt:G6PD Glutathione synthetase

c) Disorders of hemoglobin synthesis

• Deficient globin synthesis:Thalassemia syndromes

• Hemoglobinopathies (str. abnormality):

Sickle cell anemiaUnstable hb

2. Acquired

a) Membrane defect:PNH

Extrinsic abnosmalities of red cells

1. Antibody mediated

• Isohemagglutinins:Transfusion reactionsErythroblastosis fetalis

• Autoantibodies:Idiopathic (primary)Drug-associatedSLEMalignant neoplasmsMycoplasmal infection

2. Mechanical trauma to red cells

• Microangiopathic Hemolytic Anemias (MAHA)

TTPDIC

• Cardiac traumatic hemolytic anemia

3. Infections: Malaria Hookworm

4. Chemical injury: Lead poisoning

5. Sequestration in Mononuclear PhagocyteSystem:

Hypersplenism