Anemia (types): iron deficiency, megaloblastic, sickle cell


Iron deficiency anemia (iron deficiency)

The iron deficiency anemia is caused by lack of iron in the body, an essential nutrient for the realization of several basic body functions.

Hemoglobin, the main component of red blood cells, is a protein that needs iron to form, and is also responsible for transporting oxygen to the body. Thus, when an iron deficiency occurs, there is a lack of raw material, so to speak, so that these red blood cells are produced and perform their function.

Therefore, whenever the body’s iron stores are very low, iron deficiency anemia or iron deficiency anemia develops.

Many factors can cause this deficiency, such as inadequate nutrition, bleeding, heavy menstruation or malabsorption of iron by the body.

In pregnant women, due to the increase in the amount of iron needed during this period, this type of anemia can also occur.

Sickle Cell Anemia

It is a genetic and hereditary anemia, also known as  sickle-cell anemia . It happens due to a change in chromosome 11 (a structure that carries DNA). For this type of anemia to occur, 2 defective genes are needed.

In these cases, normally, the mother and father are carriers, each carrying a defective gene, but without manifestation of the disease or symptoms. However, upon receiving this genetic inheritance from the parents, the child receives the genetic combination (that is, 2 genes) to develop the condition.

When the patient has only 1 defective gene, he is identified only as having a sickle cell trait.

In this type of disease, the red blood cells are sickle-shaped, when they should normally have a more rounded shape.

Because of this variation in shape, blood cells have greater difficulty in carrying out the transport of oxygen in the required amount.

In addition, these sickle cells have a shorter duration than normal red blood cells and do not survive for long. The bone marrow, responsible for producing these cells, on the other hand, cannot keep up with the rhythm.

Therefore, the blood system is damaged. Without this replacement, several complications can happen, such as strokes, since red blood cells are responsible for the transport of oxygen and its absence can cause the death of tissues.

There are some factors that can trigger a sickling crisis, such as  stress ,  fever  and other infections. This crisis is characterized by the manifestation of symptoms such as severe pain in the bones, in the thoracic and abdominal region.

However,  sickle cell anemia  can still have great clinical variability, that is, it manifests itself severely in some patients – which can lead to more serious and frequent complications – or represent a mild and even asymptomatic clinical condition.

The diagnosis occurs right at birth, in  the heel prick test . The treatment must be done since then, with the accompaniment of a medical board.

In some cases, bone marrow transplantation may be necessary during treatment to be able to replace the marrow that is unable to produce healthy red blood cells.

This type of anemia is more common in people of North African and Mediterranean populations. In Brazil, it is much more common in the black population.

Megaloblastic anemia

Megaloblastic anemia occurs when red blood cells (red blood cells) are larger than normal, as the cytoplasm does not divide properly, usually due to the lack of necessary nutrients, due to a deficiency of vitamin B12 or vitamin B9 ( folic acid )

In addition to the variation in size, they are also less resistant and end up dying before the expected time.

This type of anemia is installed in the individual’s body due to the damage that the deficiency of these vitamins causes, because without them the body is not able to correctly perform the synthesis of thymine.

Thus, chromosomes are unable to duplicate and there is no cell division process (mitosis).

People with this condition may experience symptoms such as stomachache, tiredness ,  hair loss, mouth sores, in addition to the common symptoms of anemia, such as dizziness , weakness, dryness of the mucous membranes and pallor.

Pernicious anemia

The  pernicious anemia  is a type of megaloblastic anemia, which occurs when there is the absence of intrinsic factor (a substance produced by the stomach that aids in the digestion of food and B12 absorption in the gut).

Without the vitamin, red blood cells are produced incorrectly, dying prematurely, configuring the anemic condition.

Autoimmune factors, overuse of antacids, bariatric surgery or gastric changes may be responsible for the manifestation of the pernicious type.

Hemolytic anemias

There are different forms of hemolytic anemia, but it is characterized by the difficulty of the bone marrow in producing red blood cells that, for different reasons, are being destroyed before the appropriate time.

This can happen due to certain infectious, autoimmune, genetic or hereditary diseases, such as hereditary spherocytosis (abnormal shape of red blood cells) and the deficiency of Glucose 6 Phosphate Dehydrogenase or G6PD (which facilitates the rupture of red blood cells), for example.

In the case of autoimmune hemolytic anemia, the patient’s own immune system understands red blood cells as invaders. Thus, they produce antibodies that attack and destroy them ahead of time.

In this type, treatment depends on the cause. In autoimmune manifestation, for example, treatment with drugs that inhibit the immune system may be necessary.

Anemia of the newborn

Newborns can also suffer from anemia. The main cause of this type of problem is a disease called  fetal erythroblastosis , or Rh incompatibility.

Rh, or Rh factor, is an antigen present in the blood, which receives a positive or negative classification. When someone has the antigen naturally it is considered Rh + (positive). People who do not have this Rh factor naturally are classified as Rh- (negative).

When the baby’s positive Rh comes in contact with the mother’s negative Rh, the pregnant woman’s immune system may end up producing antibodies to defend herself against these antigens from the fetus, by understanding them as foreign bodies.

This defense system reaction is called  Rh awareness .

Because of this conflict between the mother’s and baby’s antigens, the newborn can suffer from anemia, because antibodies can cross the placenta to the fetus, causing the destruction of red blood cells.

To defend against this anemia, the newborn’s body reacts by producing immature red blood cells, called erythroblasts. This is a condition that can pose serious risks to the baby’s health.

This Rh incompatibility rarely causes problems during the first pregnancy. However, by becoming more aware, the risks in future pregnancies are greater.

Anemia due to chronic diseases

It can be caused by the presence of autoimmune diseases ,  cancer , infectious diseases, chronic kidney failure and other pathologies such as  HIV / AIDS ,  rheumatoid arthritis  and  Crohn’s disease .

Under these conditions, patients are at a greater risk of having a low production of red blood cells.