The blood is formed by a suspension of special cells in a liquid called plasma. In an adult man, the blood constitutes about 1/12 of the body weight and corresponds to 5-6 liters. 55% of the blood is made up of plasma, 45% of cells also called figurative elements: this value represents the hematocrit. The hematocrit, if raised, e.g. 50-55%, means that the blood is thickened, means that the plasma is too dense with cells and scarce in plasma and, therefore, very viscous.
Normal red blood cells
poikilocytosis or anisocytosis,
target red blood cells
These conditions are realized in some pathological conditions such as polycythemia, or polyglobulias in general, whether they are primitive or secondary, such as for example. in the bronchopathic patient. In the blood, there are special cells, classified in: erythrocytes and leukocytes. There are also platelets, which are however not considered real cells. In pathological conditions, both an increase and a decrease in red blood cells can be observed. Moreover, changes in the erythrocyte morphology may occur under different pathological conditions.
For polyglobulia we mean a stable increase in the total
circulating erythrocyte volume; for pseudopoliglobulia is meant a non-absolute
numerical increase of erythrocytes, but relative, in that it refers to the
quantity of erythrocytes per mmc (mostly transient for hemoconcentration
phenomena, as for example in the conditions in which the patient is dehydrated. A reduction of the erythrocyte heritage, known as oligocythemia, may or may
not be associated with a reduction in the hemoglobinic heritage which is
technically defined as an anemia condition, in which a reduction in the total
hemoglobinic heritage is achieved. In general, whenever a reduction in the
hemoglobinic properties occurs, as the hemoglobin is contained within the red
blood cells, there should also be a reduction in the number of red blood cells.
Changes in erythrocyte morphology include:
- Anisocytosis: presence of red blood cells with considerable variability in
size. It may be due to the presence of macrocytes (see megaloblastic anemia),
more voluminous cells than normal as in the conditions of vitamin B12 and folate
deficiency, in which the blood cells can not divide and therefore present an
excessive volume or presence of microcytes , (see microcytic anemia) cells
smaller than normal.
Megaloblastic red blood cells can be found not only in
megaloblastic anemia, but also in aplastic anemias and in the course of leukemia,
while microcytes are usually present in iron deficiency anemias, conditions that
occur when a patient loses blood slowly, for Occult bleeding, usually from the
digestive tract or with urine or genitals, if it is a woman, especially at a
fertile age. These are very common forms of medicine that more frequently
diagnoses an internist doctor. These are sideropenic hypochromic anemias, so
defined for a low content of hemoglobin in the red blood cell, which, if
calculated, is lower than the norm, therefore less than 27 picograms each
globule, and which in this case can also fall to lower values of the 30%,
compared to the norm. In addition, the doctor, reading the blood count, must
check the volume of red blood cells, which is normally around 76-80 micron cubes,
and if the VCM will be lower than these values, so if the red blood cells are
smaller, you can tell the patient that he is suffering from microcitemic anemia
or microcytic anemia. This form, as we explained above, generally depends on
occult blood loss (eg colonic diverticulosis, aspirin therapy, gastritis, etc.),
requires treatment with iron (eg emacrit, sidereal, ferrograd, ferrofolin etc.).
and other medicinal specialties containing iron with easy absorption per os). In
the hospital the internal medicine specialist can visit patients with severe
asthenia, without strength, with severe forms of microcytic anemia, which often
are also affected by ischemic heart disease. In these patients it may be
necessary to practice blood transfusions of concentrated blood cells, especially
if the hemoglobin value per dl has fallen below the threshold of 7 g / dl. Other
forms of anemia with microcytosis are found in hemolytic anemias, in
myelosclerosis but especially in thalassemia, a condition that is easy to find
in the areas of the Mediterranean where malaria existed in the past, due to the
phenomenon of natural selection, according to which the subjects do not affected
by thalassemia died due to malaria, while subjects affected by thalassemia were
immune to the mosquito anofeles, carrier of malaria. We see this in Sicily and
in Sardinia.
- Megalocytosis: oval macrocytes (megalocytes) that are found in
megaloblastic anemia; megaloblasts also have a larger nucleus than erythroblasts.
- Schistocytosis: presence of "fragments" of small blood cells (their
finding indicates an increase in hemolysis); their presence is frequent
therefore in some hemolytic anemias and in the thalassemia major.
- Spherocytosis: presence of red blood cells of normal volume, but of
smaller diameter; as a result of the increase in thickness the clearest central
area is missing. They are present in many hemolytic anemias.
- Ellissocytosis: presence of elliptic red blood cells, often similar to
rods. It is found in hereditary ellissocytosis and in megaloblastic anemia.
- Poichilocytosis: presence of pear, biscuit, racket and other abnormal
forms; it is usually found whenever there is an abnormality of erythropoiesis.
- Policromatophilia: presence of red blood cells with more or less marked
basophilic staining. The precipitate of this cytoplasmic basophilic substance in
the form of bluish dotted gives rise to basophilic punctuation.
- Hypochromia: red cells with enlargement of the central clear zone. In
some cases hemoglobin is present only at the extreme periphery of the red blood
cell (anulocytes); it is frequently found in thalassemia.
- Hypercromia: red blood cells in which the central clear zone has
disappeared, due to an increase in the globular content of hemoglobin (ECM), as
usually occurs in spherocytes.
- Target cells or leptocytes or platicitis: erythrocytes with apparent
condensation of the hemoglobin in the center, so as to appear, with the common
colors, dark in the center and the periphery with a lighter intermediate ring.
They are found in haemolytic anemias, in sickle cell disease and in HbC disease.
index hematology