Course title : Hematology (1)Course code : MLHE- 201Supervisor: Prof. Dr Magda Sultan

Date :10/10/2013

Outcome: The student will know :The importance of Hemoglobin.The importance of Hematocrit .How to calculate the red cell indices?

Red Blood Cells • Haemoglobin concentration• If red cells are lysed, the haemoglobin is released from the red cells and forms a solution in the

plasma. The haemoglobin concentration (Hb) can be measured biochemically by light absorption at a specified wave length after a chemical reaction which converts haemoglobin to cyanmethaemoglobin .

• Hb is measured in either grams per decilitre (g/dl) or grams per litre (g/l). A fall in the Hb is referred to as anaemia.  

• Haematocrit or packed cell volume• An alternative way of detecting anaemia is to

centrifuge a tube containing an aliquot of blood and measure the proportion of the column of blood which is occupied by the red cells.

• This test is called a packed cell volume (PCV) or a

• haematocrit (Hct). • This measurement is expressed as a decimal

percentage, i.e. as litres/litre (e.g. 0.45).

• Red cell indices • Red cells can vary in their size and in the amount of haemoglobin

contained in an individual cell.

• Diagnostically useful informations can be obtained by measuring the red cell indices :

Mean cell volume (MCV). Mean cell haemoglobin (MCH). Mean cell haemoglobin concentration (MCHC).

• 

The formulae which relate the various red cell indices to each other are as follows:

MCV is measured in femtolitres

MCH is measured in picograms

MCHC is measured in g/dl

• Normal ranges • In order to interpret blood counts it is

necessary to know what is normal. This is usually done by reference to either a normal or a reference range.

• Assessing Red Cells • Red cells should be assessed as to their:• number• size• shape• degree of haemoglobinization• distribution in the blood film.

• Assessing red cell number and distribution -Anaemia -Polycythaemia - Rouleaux formation - Red cell agglutination

 

• Normal distribution of red cells in a healthy subject with normal Hb.

• Anaemia (caused by iron deficiency)

• Polycythaemia.

• Rouleaux

• Red cell agglutinates

• Assessing red cell size: -Microcytosis. -Macrocytosis. -Anisocytosis. • If cells are smaller than normal they are described as microcytic and if larger than

normal as macrocytic.• Red cells of normal size are said to be normocytic. • If red cells show greater variation in size than normal the blood film is said to show

anisocytosis .

• •

• Normocytic red cells.• 

• Microcytic red cells (MCV 62fl )

• Macrocytic red cells (MCV 105 fl)

• Anisocytosis

• Assessing red cell shape (poikilocytosis)• • If red cells show more than the normal degree

of variation in red cell shape there is said to be poikilocytosis

Diagrammatic representation of different types of poikilocyteDiagrammatic representation of different types of poikilocyte

• Moderate numbers of spherocytes (in hereditary spherocytosis

• Several irregularly contracted cells (in haemoglobin C disease).

• The majority of the other cells are target cells.

• Numerous elliptocytes and ovalocytes (in hereditary elliptocytosis).

• Several dacrocytes (tear-drop poikilocytes) (in idiopathic myelofibrosis).

• Numerous stomatocytes (in hereditary stomatocytosis).

• Several keratocytes (in microangiopathic haemolytic anaemia);

• keratocytes are sometimes called ‘bite cells’ because they look as if a bite has been taken from them

• Several schistocytes (red cell fragments) including a microspherocyte (in haemolytic uraemic syndrome)

• Echinocytes (crenated cells) (in chronic renal failure)

• Acanthocytes (in abetalipoproteinaemia

• One sickle cell and several boat-shaped cells (in sickle cell anaemia )

• Assessing red cell colour: - Normochromic - Hypochromic

• Normochromic red cells

• Hypochromic red cells

AssignmentStudents names Assignment

العاطي عبد مصطفي الشيماءاحمد محمد امل

يوسف اسعد اميرهمرشدي صالح اميره

الموجود عبد انجياشرف اوركيد

محمد سعيد ايمانيوسف محمدي ايمانالعزيز عبد رجب ايه

عطيه حماده ايه

Counting chamber in cell counts .

ناجي عوض ابانوبنظير سدراك باخوم

محمد خالد باسمرياض مهدي بسمه

محمد اشرف بسنتعلي حسن بسنتابراهيم محمود تغريدحسين الدين حسام

منصور حسين حسامعشري محمد حماده

Red cell assessment.

• Training Questions : • What are the red cell indices formulae ? • Mention the different red cell shapes . • How to assess red cells regarding their size ?

Reference book- Dacie- Essential Haematology