ANEMIADEFINITION &

CLASSIFICATIONMaj Gen (R) Masood Anwar

Professor of Haematology

Functions of blood◦ Transport of nutrients◦ Transport of gases◦ Haemostasis◦ Defence

Composition of blood◦ Cells (RBC, WBC, Platelets)◦ Plasma (Colloids, Crystalloids, Water)

DEFINITION

PYSIOLOGICAL DEFINITION◦ Decrease in oxygen carrying capacity of blood.

ANALYTICAL (PATHOLOGICAL) DEFINITION◦ Reduction in total circulating red cell mass◦ Reduction in Haemoglobin concentration and/or

Haematocrit

DEFINITION

These are blood cells produced in the bone marrow from a pleuripotent haemopoietic stem cell by processes of division, differentiation and maturation and released in the circulation to function mainly to transport oxygen from lungs to other tissues of the body.

RED BLOOD CELLS

RED BLOOD CELL

Haemoglobin (Hb) Haematocrit (Hct) [Packed Cell Volume (PCV)] Total Red Blood Cell Count (TRBC) Mean Cell Volume (MCV) Mean Cell Haemoglobin (MCH) Mean Cell Haemoglobin Concentration

(MCHC) Red Cell Distribution Width (RDW)

MEASUREMENT OF RED BLOOD CELL MASS AND INDICES

PARAMETER ADULT MALE ADULT FEMALE

Hb 13-17 g/dl 12-16 g/dl

TRBC 4.5-6.5 X 1012/l 4.2-6.0 X 1012/l

Hct/PCV 40-54%/0.40-0.54 l/l 36-49%/0.36-0.49 l/l

MCV 76-96 fl

MCH 27-32 pg

MCHC 31.5-34.5 g/dl

NORMAL VALUES

MORPHOLOGICAL CLASSIFICATION Based on appearance of RBC under the

microscope OR red blood cell indices PATHOLOGICAL CLASSIFICATION

Based on abnormality of anatomical, biochemical or physiological abnormality

ETIOLOGICAL CLASSIFICATION Based on specific causative process/agent

CLASSIFICATION

MORPHOLOGICAL CLASSIFICATIONNormocytic normochromic anaemia

MORPHOLOGICAL CLASSIFICATION

Hypochromic Microcytic Anaemia

Iron deficiency anaemia Thalassaemia minor Sideroblastic anaemia Anaemia of chronic disorders

HYPOCHROMIC MICROCYTIC ANAEMIA

MORPHOLOGICAL CLASSIFICATION

Macrocytic anaemia

Megaloblastic anaemia Aplastic anaemia Myxoedema Chronic Obstructive Pulmonary Disease Liver Disease Myelodysplastic syndromes

MACROCYTIC ANAEMIA

Blood loss◦ Acute◦ Chronic

Decreased production◦ Disturbance of proliferation and differentiation

Of stem cells Of erythroblasts

◦ Defective Hb synthesis Increased destruction

◦ Intracarpuscular (Intrinsic) defects◦ Extracarpuscular (Extrinsic) defects

PATHOLOGICAL CLASSIFICATION

Hereditary◦ Blood loss – Hereditary Intestinal telengiectasia◦ Decreased production – Pure Red Cell aplasia◦ Increased destruction – Membrane, Enzyme and Hb

defects Congenital

◦ Defective production – Congenital dyserythropoietic anaemia,Congenital sideroblastic anaemia

◦ Increased destruction – Cardiac defects, vascular defects

Acquired

ETIOLOGICAL CLASSIFICATION

Blood loss◦ Acute◦ Chronic

Ulcerative lesions of GIT Female reproductive system Parasites – Ankylostoma duodenale, Schistosoma

haematobium

ACQUIRED ANAEMIAS

Increased destruction of RBC◦ Membrane defect (PNH)◦ Mechanical trauma (Microangiopathies)◦ Antibody mediated (Immune haemolytic anaemia)◦ Parasites (malaria, Aroya fever)

ACQUIRED ANAEMIAS

Decreased production◦ Deficiency anaemias

Iron deficiency Vitamin B12 and Folate deficiency

◦ Bone marrow disease/infiltration◦ Miscellaneous

Pyridoxin responsive anaemia Sideroblastic anaemia

ACQUIRED ANAEMIAS