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Composition:
suspension of cells in a complex liquid (plasma)
Plasma: * H2O + organic molecules + mineral salls
* After coagulation (- Fibrinogen) = serum
Blood Cells:
* R.B. C
* W. B. C.
* platelets.
Origin:
Site:
* In the embryo (Liver, Spleen, Bone marrow)
* After birth (only in the Bone marrow)
* Lymmphoid tissues (B.M., L.N., Spleen, Payer's patches)
HEMOPOIESIS
1-Erythropoiesis:
The erythroblastic line represents 10 -30% of the
bone marrow cells.
2-Steps of maturation: It take 7 days under
normal condition.
1- Erythroblast (pronormoblast)
2-Basophilic Normoblast
3- Polychromatic normoblast.
4-Orthochromatic normoblast.
5-Reticulocyte
6- R. B. C
4-In Cases or Urgent Blood Loss:
E.g.: - after haemolytic attack
- after Hge
1- Hypersecretion of erythropoietin
2- Augmentation of no. of erythroblasts in B. M. resulting
in:
3- Acceleration of Hb. synthesis normal corpuscular conc.
or Hb. occurs early
decrease the number of cell
divisions between stage of erythroblast and reticulocytes -reduction of duration of erythropoiesis to 3-4 days.
N.B as a result of Hyper secretion of the erythropoietin and
acceleration of Hb. synthesis. Hypererythropoiesis occurs.
HYPERERYTHROPOIESIS
a- Increase in number or reticulocytes in the peripheral blood
b- presence of immature R.B.CS (polvchromatophilia )
c- Macrocytosis. (duo to reduction of number of mitoses
between proerthroblasts and Reticulocytes)
d- Some orthochromatic normoblasts may be found in the
peripheral Blood
5-Exogenous Factors necessary for Erythropoiesis:
1-Iron
2-Folic acid and Vitamin B12
EXAMINATION OF THE BLOOD:
COMPLETE BLOOD PICTURE (C.B.C.)
A-QUANTITATIVE EXAMINATION:
1-Quantitative Exam. of the RBCS with its constituents:
aR.B.Cs no./mm3:
Male
4.5 – 6.2 x 106
Female & Child:
4 – 5.4 x 106
Infant
3.6 – 5 x 106
at Birth
5–6
x 106
b- Hematocrite:
(relative volume of R.B.CS in the blood)
- By centrifugation of a small column of blood in a
standard tube:
Male
40 - 54 %
Female
35 - 47 %
c- Hb. Content of 100 cc blood:
Male
Female & Child:
Infant
at Birth
13 - 18 gm/100cc
12 - 16 gm/100cc
12 - 16 gm/100cc
14 - 20 gm/100cc
f- Reticulocytic count:
-
Normal life span of RBCs = 120 days
- Reticulocytes are the newly fabricated RBCs within the
1st 24 hours (still containing cytoplasmic organelles) i.e. --by special stain --- counting the no. of RBCs containing such
organells among 1000 RBCs in %.
- Absolute no. of reticutocytes: = RBCs count X
reticulocytic %.
* normal 25.000
----- 100.000/mm3 (l-2 %)
For Hb content within the normal range.
* with anaemia increase in no. of the reticulocytes , if there is
a normal ability of the B.M. to synthesis RBCs
i.e., If Hb <= 8 gm in regenerative anaemia (e.g., haemolytic or
post Hgic) -- reticulocytic count must be > 100.000 . If <
100.000 this means aregnerative, i.e., ( hypoplastic or aplastic )
anaemia.
2-
Quantitative Exam. of WBCS:
Normal
4.000
--- 10.000/mm3 in adults
Infants 1st year
5.000 - 20.000 /mm3
2nd year
6.000 – 17.000 / mm3
10 years
5.000 --- 13.000/mm3
N.B. In adult.
* > 11.000 indicates leucocytosis
* < 4.000 indicates leucopenia.
3- QUANTITATIVE
PLATELETS:
Normal
ESTIMATION
l50.000 - 450. 000/mm3
< 150,000 indicates thrombocytopenia.
>450.000 indicates thrombocytosis
OF
B- MORPHOLOGIC EXAMINATION:
RBCs
WBCS
Morphological exam. of RBCs.
Differential white cell count.
I- Morphologic Examination of RBCs:
Normally : RBCs are of * same form
* same colour
* same diameter.
Any abnormality
Pathological condition:
* in size : anisocytosis
* in form: poikilocytosis
II- Differential white cell Count:
-The absolute no. more important than the %
Polymorphonuclear Neutrophils:
* 40 – 70% of WBCS (1700 - 7000)
* Function:
The main Function is phagocytosis of
foreign bodies esp. Bacteria
Granulopoiesis: It takes 10 days under normal conditions
50 -70 % of B. M. cells
- Myeloblasts
2.3 %
- Promyelocytes
4-8%
- Myelocytes
10-15%
- Metamyelocytes 15-20%
- Polynuclear cells 20-30%
* Life span: in the circulation is very short within 12
hours . 50% of formed neutrophils leave the blood to the
tissues and don't turn back again.
In cases of excess demand:
Rapid passage of neutrophils to the blood from the
marrow resulting in the release of band forms, even
metamyelocytes and myelocytes.
Polymorphonuclear leucocytosis:
Due to increase polymorphonuclear neut. i.e.> 7000/ mm3
1- Reactional:
a- physiologic:
- Neonates
- Severe exercise
- Menestruation
- Pregnancy
b- Pathologic:
-
-
Bacterial infections
Inflammatory diseases : (Arthritis - Allergic )
Tissue necrosis e.g., rnyocardial Infraction,
pancreatitis
Heavy smokers.
Acute hemorrhage or hemolysis
Intoxication (radiation, benzene)
Start of chronic myeloid leukemia
Without cause
2- Myeloproliferative disorders: as Chronic
Myeloid 1eukemia
Neutropenia:
means that Neutrophils < 1700 / mm3, It is due to
either:
1- Insufficient production (central):
A- As a part of Pancytopenia: e.g., aleukemic leukemia
or aplastic amenia
B- Isolated:
1- Hereditary form.
2- Allergy to certain drugs
3- Direct central inhibition e.g., henothiazine
4- Constitutional agranulocytosis.
2- Hyperdestruction (peripheral):
- Auto immunisation
- Lupus Erythromatosis . Usually with
thrombocytopenia
- Felty's syndrome
# But espe. in moderate cases (i.e. 800- 1700) we
must exclude :
-Some parasitic infections (kala Azar)
- Some bacterial infections (typhoid, Brucellosis)
- Some viral infections (Viral hepatitis)
- May be normal esp. in black races.
Eosinophiles:
* Functions: (not exactly known)
- phagocytosis : Ag- Ab complex
- Transport the plasminogen
- Play a role in destruction of certain larvae
- Has a role in allergy
Eosinophilia:
means eosinophils > 300/mm3 but more significant if >
500/mm3
causes:
1- Allergic conditions:
- Asthma,
- Allergy to certain drugs as penicillin's.
2- parasitic infections:
Filariasis, Ascaris, Oxyuris, Taeniasis.
3- Polyarteritis nodosa
4- Dermatosis
5- Malignancy:
- H.D
- certain cancers (Liver, Ovary)
Basophils:
* Function:
- Unknown.
- Rich in histamine and heparin
- Play a role in delayed hypersensitivity reaction
If >1 % = pathologic conditions:
1- Myeloproliferative syndromes esp. C.M.L
2-Severe hyperlipidaemia
3- Hypothyroidism
Monocytes:
- The largest circulatory blood cells, have:
* characteristic Nuclear shape,
* Longer life span than other WBCs (2-3 days)
Function:
1- phagocytosis : Play a role in defence mechanism
In tissues --- Macrophages
2- Play a role in immunologic reactions
Monocytosis:
means monocytes > 1000 /mm3:
1- reactional:
- infections: (bacteria, virus parasites)
- At the recovery of agranulocytosis
2- Acute monocytic leukemia, chronic myelomonocytic
leukemia
3- Isolated chronic Monocytosis :
rare as in refractory anaemias at the start of acute
monocytic Leukemia, and chronic myelomonocytic
eukemia.
Lymphocytosis:
Means increased number of lymphocytes above the upper
limit of normal (> 4000 – 4500/cumm in adults , > 60007000 , cu mm in neonates and infants.
Causes:
1. Viral
infections : hepatitis, measles, infective
mononucleosis
2. Bacterial infections : brucellosis , T.B., whooping
cough.
3. Malignant
lymphocytosis : Chronic lymphatic
leukemia and Waldestron’s macroglobulinemia.
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