LAP 2

LAB2
Complete blood count (CBC)
•?We can define the CBC as many tests which determine the different component of blood (cells or Hb). A major portion of the CBC is the measure of the numbers of white blood cells, red blood cells and platelets in the blood. The CBC can provide important information on the types of blood cells, their condition, and numbers; this can help in diagnosis many condition and diseases, such as anemia, leukemia and inflammation.

The CBC includes many tests :-
1- Hemoglobin (Hb) determination.
2- Hematocrite of Packed Cell Volume (P.C.V.)
3- Erythrocyte Sedimentation Rate (E. S. R.)
4- Red Blood Cells Count (R.B.C count)
5- White Blood Cells Count (W.B.C count)
6- Differential W.B.C count
7- Platelets count
Hemoglobin (Hb) Determination :-
Hb is a respiratory pigment of red blood cells that carries O2 and CO2. each R.B.C. contain about 252 m. molecules of Hb. A molecule is a tetramer made up of four monomers. The monomer consists of a heme (Pigment with iron) and Globin unit (protein). The globin units are made up of 4 polypeptide chains (2 ? chain & 2 ? chain) there are many normal types of Hb such as fetal Hb (HbF) which is gradually replaced by adult Hb (HbA).
Hb values are affected by age, sex, pregnancy, disease, and altitude. During pregnancy increase in body fluids lead to the red cells become less concentrated, causing the red cell count to fall. Since the Hb inside the red cells, also falls. Disease may also affect the values of Hb for example; anemia drops Hb values. Above normal Hb values may occur. In dehydration or change in altitude, at higher altitude there is low O2 pressure in the air resulting in an increase in red cells and Hb values.