Introduction and classification of

anemia’sBy Anmol Jain

2ndYear MBBS

ESICMC-PGIMSR

OBJECTIVESAt the end of this lecture, one

should know:

1. Simple basics about

erythrocytes

2. Important terminology related

to RBC’s

3. Definition of anemia

4. Clinical features and Signs

and Symptoms

5. Classification of anemia

CONTENTS

Introduction to RBC’s

RBC cell indices and Haemeglobin

Anemia- Definition

Signs and symptoms

Investigations

Pathophysiologic classification

Morphological classification

Introduction To RBC The mature erythrocytes are non-

nucleated cells and lack usual cell organelles.

The normal RBC is biconcave in shape,7.2µm in diameter and has a thickness of 2.4µm at the periphery and 1µm in the center.

The biconcave shape helps the RBC to pass through the smallest capillaries

90% of the RBC’s weight is concentrated in the red pigment hemoglobin and the RBC’s have a lifespan of 120±30 days.

Functions of RBC’s• The most important function of an

RBC is the transportation of oxygen

to tissues with the help of HbA

present in normal adults.

• The 4 units of HbA take up oxygen in

succession which results in stepwise

affinity of hemoglobin for oxygen

and thus is responsible for the

sigmoid shape of the oxygen

dissociation curve

• Another important function of RBC’s

is the transportation of CO2 from the

tissues to the lungs.

Normal Values• Range of normal RBC count is:5.5±1.0

and 4.8±1.0 ×1012/L and the Hemoglobin

content being 15.5±2.5(13-18)g/dl and

14.0±2.5(11.5-16.5)g/dl in Men and

Women respectively.

• The packed cell volume or the

haematocrit is the volume of the

erythrocytesper litre of whole blood is

40-54% and 37-47% in Men and Women

respectively

• Based on these normal values red cell

indices have been devised,which are of

diagnostic importance.

RED CELL INDICES

Haemoglobin

• Haemoglobin is a

basic protein,GLOBIN

and of iron-porphyrin

complex HEME with a

molecular weight of

68,000 and consists of

4 polypeptides.

• Normal adult

hemoglobin is-α2β2

which is called HbA

and other forms also

exist such as

HbF(foetal) and HbA2.

RBC Destruction and Recycling

ANEMIA• DEFINITION:Anemia is defined as the clinical condition

which is caused by a reduced number of RBC’s or

reduced hemoglobin concentration in the blood

below the lower limit of the normal range for the age

and sex of the individual.

• In Adults the lower value is taken as 13.0g/dl and

11.5g/dl of normal haemoglobin for men and women

respectively.

History of Anemia• The word "anemia" is composed of

two Greek roots that together mean "without blood," but to use this literal translation as a definition would be a gross exaggeration.

• The ancients readily recognized the importance of blood as a life- giving substance, believing it to hold the body's vital force. Hebrews back to the patriarchal age maintained that blood was the seat of the soul and demanded through the Mosaic Laws that it be drained before an animal was prepared as food (a practice still followed by Orthodox Jews today). The Romans drank the blood of their enemies, thinking it would confer on them the courage of their vanquished foes.

Signs and Symptoms

Investigations Haemoglobin Estimation

Peripheral blood smear

examination

Red cell indices

Leucocyte and platelet count

Reticulocyte count

Erythrocyte sedimentation

rate

Bone marrow examination

Classification

• Classification of Anemia’s is done in 2 types:

1. Pathophysiological classification

2. Morphological classification

Pathophysiological Classification

1. Anemia due to increased blood loss:a. Acute post-hemorrhagic anemia

b. Anemia of chronic blood loss

2. Anemia due to impaired RBC production:a.Cytoplasmic maturation defects

Eg: Deficient heme synthesis-Iron deficiency Anemia

Deficient Globin synthesis-thalassemia

b.Nuclear maturation defects

Eg:Megaloblastic anemia

c.Hematopoetic stem cell proliferation and

differentiation abnormality

Eg:Aplastic anemia

Pure red cell aplasia

d.Bone marrow Failure due to systemic diseases

Eg: Anemia in renal disease/inflammation

e.Bone marrow infiltration

Eg: Leukemia,Lymphoma etc

f.Congenital anemias

Eg:Sideroblastic anemia

3.Anemia due to increased RBC destruction

a) Intracorpuscular Defects

Eg:Hereditary Spherocytosis

b)Extracorpuscular Defects

Eg:Auto immune hemolytic disorders

Morphological Classification

THANK YOU