��Pathology of red blood cells��
Lecturer: Associate Professor of Pathophysiology, PhD�Oliievska S.
��The main function of erythrocytes is to transfer oxygen from the lungs to the tissues and carbon dioxide from the tissues to the lungs��
Erythron
2) organs of erythropoiesis and structures where the destruction of old and defective erythrocytes take place
3) the apparatus of regulation (including nerve and endocrine glands)
Erythropoietins
glycoproteins with a molecular weight of 34000
They are formed mainly in the interstitial peritubular cells of the kidneys (90%) and in the liver (10%).
Their synthesis depends on the oxygen content not only in the tissues of the kidneys and liver, but also in other organs.
Erythropoietin stimulants
Regulators of erythropoiesis
Growth hormone and somatomedins, insulin, thyroxine and triiodothyronine; prostaglandins, adenosine – stimulants
Theophylline – blocks.
Hypoxia
Androgens
Adrenaline
Noradrenaline
FACTORS OF ERYTHROPOIESIS
Price-Jones curve �shows the percentage of erythrocytes of different diameter in the blood.
Shift of Price-Jones curve to the left
means the increase in the quantity of erythrocytes of small diameter in the blood smear, i.e. the tendency to microcytosis.
Shift of Price-Jones curve to the right
means the increase in the quantity of erythrocytes of bigger diameter in the blood smear, i.e. the tendency to macrocytosis.
Erythrocytometry - measurement of the diameter of the red blood cells.
Distribution of erythrocyte diameter in percent in healthy people
5 mcm — 0.4% of all erythrocytes;
6 mcm — 4%;
7 mcm — 39%;
8 mcm — 54%
9 mcm — 2,5%.
CELLS OF PHYSIOLOGICAL REGENERATION
Anisocytosis �is the appearance in blood of different diameter erythrocytes, the base of Price-Jones curve increased
Poikilocytosis
is the appearance of abnormal red blood cells or erythrocytes of different forms (oval, drop, sickle-form) in the blood smear.
Aniso- and poikilocytosis
usually develops in different types of anemia especially in iron and vitamin В12-folic acid deficiency anemia.
Erythrocytosis
is a condition that is accompanied by an increase in the number of red blood cells and hemoglobin in the blood
(blood concentration)
CLASSIFICATION OF ERYTHROCYTOSIS:
According to origin | According to pathogenesis |
Physiological Pathological | Absolute Relative |
�ACCORDING TO ORIGIN �
Physiological | Pathological |
- in people living at a high altitudes in the mountains; - in newborns just after the birth; - in physical exercises. Increase in the quantity erythrocytes in these cases results from hypoxia, stimulation erythropoesis or as a result of redistribution erythrocytes between depot and the circulating blood |
|
�ACCORDING TO PATHOGENESIS�
Absolute | Relative |
as the result of erythropoiesis stimulation. In pathology conditions, such stimulation of erythropoiesis is found in cardiac and respiratory insufficiency, erythropoietin-secreting tumors, when there is a lot of released erythropoietin and intoxication by small doses of phosphor, cobalt, manganese, copper. | as a result of a quantitative decrease of blood plasma. The quantity of blood erythrocytes becomes relatively increased. Such a phenomenon is found as a result of dehydration, for example in cholera, profuse perspiration, water deficit. |
ABSOLUTE ERYTHROCYTOSIS DEVELOPS IN HYPOXIA
Oxygen deficit causes the activation of endocrine glands (hypophysis, thyroid and adrenal glands) and the increased synthesis of erythropoietin in kidneys.
It stimulates metabolism in cells of red bone marrow as well as maturation and the release of erythrocytes into the blood flow circulation
Erythremia
is a malignant disease of hemopoietic system resulting from common proliferation of all blood cells in the hemopoietic tissue, characterized by a prolonged progressive course of the disease, quantitative increase in all blood cells and the volume of circulated blood, the increase of the systemic arterial blood pressure and the tendency to thrombosis.
Anemia
hematologic syndrome or a distinct disease (typical form of pathology of the blood system), the pathogenetic basis of which is a decrease in blood hemoglobin (and, as a rule, the erythrocytes), as well as qualitative changes of red blood cells, leading to the development of hemic hypoxia. �
CLASSIFICATION OF ANEMIA
ACCORDING TO ETHYOLOGY: | Hereditary Acquired |
ACCORDING TO PATHOGENESIS: | Posthemorrhagic Caused by impaired erythropoiesis. Hemolytic |
ACCORDING TO THE COLOUR COEFFICIENT (CI) | Hypochromic. Normochromic. Hyperchromic |
ACCORDING TO DIAMETER OF ERYTHROCYTES : | Microcytic (in iron deficiency). Normocytic (in hypo-aplastic anemia). Macro- and megalocytic (in vitamin В 12-folic acid deficiency). |
CLASSIFICATION OF ANEMIA
ACCORDING TO ABILITY OF RED BONE MARROW TO REGENERATION | Hyperregenerative Regenerative Hyporegenerative Aregeneretive Aplastic |
ACCORDING TO THE TYPE OF ERYTHROPOIESIS: | Normoblastic Megaloblastic (in vitamin Bi2-folic acid deficiency) |
ACCORDING TO THE CLINICAL MANIFESTATION: | Acute Chronic |
POSTHEMORRHAGIC ANEMIA
Etiology: Bleeding due to trauma or some pathologic processes.
Characteristics of the blood in acute posthemorrhagic anemia: an increase in the amount of reticulocytes up to 8 -10 % and a slight decrease in the colour coefficient (normochromic anemia).
DYSERYTHROPOIETIC ANEMIA
the disorders of renal and hepatic function,
the hypofunction of hypophysis, thyroid, adrenal glands,
the atrophy of stomach mucosa can lead to anemia due to impaired erythropoiesis
IRON -DEFICIENCY ANEMIA
Etiology: iron deficit and the disorder of erythropoiesis are produced by chronic bleeding (stomach, intestinal, uterus, hemorrhoid), pregnancy and hunger (starvation).
Characteristics of the blood in iron deficiency anemia are: microcytosis, hypochromia,aniso-poikilocytosis, hyporegenerative anemia.
HYPOCHROMIA
is enlightenment of erythrocytes colour due to the hemoglobin content decrease in them.
Hypochromic erythrocytes
are found in iron deficiency, in anemia due to impaired erythropoiesis (in kidney insufficiency hypofunction of thyroid gland and hypophysis).
Such type of anemia can be a result from disorder of synthesis of heme and globin.
THE PATIENT'S BLOOD WITH IRON DEFICIENCY ANEMIA
Dry skin, nail bundle
B12-FOLIC ACID DEFICIENCY ANEMIA
Etiology :
- disorder of absorption in the intestine (resection, polyposis, invasion of Diphylobotrium latum).
�Main biologic effects of vitamin BI2:�
- Regulation of DNA synthesis in cells.
- Regulation of lipid acid exchange in nerve cells.
�THREE MAIN GROUPS OF DISORDERS CAUSED BY VITAMIN B12-FOlIC ACID DEFICIENCY ANEMIA:�
BLOOD CHARACTERISTICS IN VITAMIN B12-�FOLIC ACID DEFICIENCY ANEMIA
Hyperchromic anemia;
Macro- megalocytosis, megaloblastosis;
Presence of Kebot rings, Jolly bodies inside of erythrocytes;
leuco- and thrombocytopenia;
Such manifestations results from megaloblastic erythropoesis.
Erythrocytes in the blood are hemolysed and the amount of non-conjugated bilirubin is increased.
BLOOD OF A PATIENT WITH B12-DEFICIENT ANEMIA
�Main gastrointestinal manifestations caused by vitamin B12-folic deficiency anemia:�
Mucosa atrophy due to the impaired DNA synthesis in tongue, stomach and the intestine epithelium.
Main manifestations in the nervous system in vitamin B12-folic acid deficiency anemia:
The disorders of lipids exchange lead to a decreased formation of myelin and degenerative changes in die posterior columns of spinal cord. These are manifested as funicular myelosis.
HYPO-APLASTIC ANEMIA
Anemia due to hypoplasia or aplasia of red bone marrow.
Etiology:
It is caused by the effect of ionizing energy, cytostatics, drugs (sulfanilamides, antibiotics, especially levomycitin), hypofunction of kidneys, thyroid, adrenal glands, hypophysis, tumor metastasis to bone marrow.
CHANGES IN THE BLOOD COUNT CAUSED BY HYPO-APLASTIC ANEMIA
Decrease in erythrocytes, leukocytes, thrombocytes (pancytopenia), hemoglobin, hematocrite. Normal colour coefficient.
MAIN CAUSES OF DEATH CAUSED BY HYPO-APLASTIC ANEMIA ARE:
HEMOLYTIC ANEMIA
is anemia due to splitting (hemolysis) of erythrocytes.
It can be inherited and acquired.
Hemolysis occurs predominantly within the mononuclear phagocytes or intravascular.
MAIN REASONS OF ACQUIRED HEMOLYTIC ANEMIAS
Immunologic conflict due to the presence of isohemagglutinines (hemotransfusal shock, hemolytic disease in newborns).
Hemolytic poisons (snake poison, salts of heavy metals).
Infection (including malaria).
Burning disease.
Mechanical damage of erythrocytes (artificial valves, vessels).
�MAIN REASONS OF HEREDITARY HEMOLYTIC ANEMIAS ARE THE FOLLOWING:�
�CLINIC-LABORATORY MANIFESTATIONS CAN APPEAR IN ACUTE HEMOLYTIC ANEMIA:�
�CHANGES IN PERIPHERAL BLOOD AND ERYTHROPOIESIS CAUSED BY ACUTE HEMOLYTIC ANEMIA�
PECULIARITIES OF PERIPHERAL BLOOD SHIFTING CAUSED BY HEMOLYTIC ANEMIA.