BLOOD Modified type of CT
Blood constituents: • A. Blood plasma:55% of blood volumeincludes: • 90 % water. • 10 % : inorganic saltsand organic substances: mainly plasma proteins (albumins, globulins, fibrinogen and prothromin).
B. blood elements: These constitute about 45 % of total blood volume. They are the: • 1-red blood corpuscles (R.B.Cs) • 2-the white blood cells (W.B.Cs) or leukocytes including a-the granular leucocytes (neutrophils, eosinophils, basophils) and b-the agranular leucocytes (lymphocytes, monocytes) • 3-the blood platelets
R.B.Cs count: • Average R.B.Cs count in normal malesis 5 - 5.5 millions / mm3 blood, whereas in females it is 4.5-5 millions / mm3 blood. • Life Span of R.B.Cs.: • It is about 100-120 days..
Shape: biconcave discs. Nucleus: non nucleated. Size: their diameter ranges between 7.2-7.8 in blood films. It’s cytoplasm: contains Hemoglobin concentrated at the periphery.
Abnormalities in R.B.Cs.: • Abnormalities in the number of R.B.Cs: • i- Polycythaemia: i.e. increase in the total number of R.B.Cs. • ii- Anaemia: i.e. decrease in the total number of R.B.Cs.
Abnormalities in the size of R.B.Cs.: • Anisocytosis: when there are R.B.Cs. of variable sizes. • i- Microcytes: when the diameter of R.B.Cs.is less than 6. • ii- Macrocytes: when the diameter of R.B.Cs.is more than 10.
Poikilocytosis: when R.B.Cs present in a blood film with variable shapes. • Sickle cell anaemia
Leucocytes • Normal Count: • The average total W.B.Cs. count is 4000-10000 / mm3 blood.
Granular leukocytes A-Neutrophils B-Eosinophils C-Basophils
Neutrophil Barr’s body
Functions of Neutrophils: P.N.Ls (neutrophils) are the first line of defense against any invading micro-organism
Abnormal Neutrophil Count: -Neutrophilia: i.e. abnormal increase in the number of neutrophils. This is observed in acute inflammations e.g. appendicitis, tonsillitis. -Neutropenia: i.e. abnormal decrease in the number of neutrophils e.g. in influenza, typhoid fever.
Function of Eosinophils: They are responsible for regulation of allergic immune reactions.
Abnormal Eosinophil Counts: 1-Eosinophilia: i.e. abnormal increase in the number of eosinophils as in: - Allergic reactions e.g. asthma, urticaria -Parasitic infections e.g. Bilharziasis. 2-Eosinopenia:i.e. abnormal decrease in the number of eosinophils e.g. as result of prolonged corticosteroid therapy .
Function of Basophils: Basophils are responsible for the release of Histamine in systemic allergic reaction
Monocyte 3-8% Kidney-shaped nucleus platelets
Functions of Monocytes: Monocytes are phagocytic cells. Abnormal Monocytes Count: Monocytosis: is an abnormalincrease in the number of blood monocytes. It occurs in diseases like malaria, typhus, viral infections
Lymphocytes 20-25% Large, indented nucleus
Abnormal Lymphocytic Count: Lymphocytosis: It is an abnormal increase in the number of lymphocytes as in: -lymphatic leukaemia - chronic infections e.g. tuberculosis, syphilis, whooping cough.
Platelets 150,000-350,00/mm3 (about ¼ - ½ million/mm3).
Function of Blood Platelets: Blood platelets are concerned with: - the process of thrombus formation (blood clotting) in response to any vascular endothelial injury to prevent excessive blood loss. - clot retraction and removal of the blood clot after healing of the vessel wall to re-establish the flow of the blood.