Anemia is a “pathological condition” in which there is a decrease in the proportion of red blood cells circulating in our body. It is recognized mainly by the laboratory control and the determination with the general blood of the indicators, such as the hematocrit, the hemoglobin concentration and the number of red blood cells per cubic centimeter of blood.

Anemia as such is not a disease, but is the result of underlying conditions or diseases, the finding of which will help determine the type of anemia. Whether a patient is symptomatic or not depends on the etiology of the anemia, whether it is acute or not, or the presence of other serious comorbidities. Most patients experience anemia-related symptoms when their hemoglobin is <7.0g/dL.

Epidemiologically anemia is an extremely common condition, which it affects 1/3 of the world’s population. The frequency increases with age, it is more common in women of reproductive age, pregnant women and the elderly. Other vulnerable groups are alcoholics and the homeless.
The pathophysiology of anemia varies and depends mainly on the primary cause that caused it.

Main mechanisms of causing anemia can be:

1. The increased destruction of red blood cells.

a) From blood loss that can be caused by acute bleeding, intraoperative, from injury, from chronic and heavy menstruation in women, chronic blood loss from the gastrointestinal or urinary tract.
b) From hemolysis, as in autoimmune hemolytic anemia, in infections, in hypersplenism.
c) From hereditary enzyme diseases, hemoglobin disorders, a defect in red blood cell metabolism (G6PD, PK) or a defect in the red blood cell membrane (spherocytosis, elliptocytosis).

2. Deficient erythropoiesis occurring in:

a) Microcytic anemia
b) Normocytic anemia
c) Macrocytic anemia

What are the symptoms of anemia?

The symptoms of the anemic person depend on one hand on the severity of the anemia, the speed with which it settled, but on the other hand on the underlying disease that caused it.

Anemia is recognized as pallor of the skin and conjunctivae.
It can cause symptoms such as fast heart rate, feeling tired, shortness of breath when tired, wheezing, dizziness, tinnitus, headache.

Classification

The causes of anemia can be classified based on the pathophysiological cause into three main categories:

1. Decreased red blood cell production due to:
a) lack of erythropoietic factor in the synthesis of heme (iron deficiency anemia), in the synthesis of DNA (megaloblastic anemia).
b) in an unknown mechanism (anemia of chronic diseases)
c) in myelophthisic anemia (leukemia, lymphomas)

2. Hemolytic anemia due to the destruction of red blood cells.
a) hemolytic anemia due to intraerythrocytic causes (Mediterranean anemia, sickle cell anemia).
b) hemolytic anemia from extraerythrocytic causes (autoimmune hemolytic anemia)

3. Post-hemorrhagic anemia which is due to blood loss
a) bleeding from the digestive tract due to gastro or enterobleeding
b) bleeding from the urinary tract (hematuria)
c) bleeding from the respiratory tract (hemoptysis)
d) major injuries

The morphological classification of anemias is based on mean red cell volume (MCV) and mean hemoglobin density (MCHC), according to which they are classified into:
a) microcytic hypochromic anemia (such as iron deficiency anemia or ironblastic anemia)
b ) macrocytic anemia
c ) normochromic anemia

How is anemia diagnosed?

The approach to anemia will be based on the type of anemia.

Laboratory testing includes:

1. The general blood and the morphological assessment of the plate
2. Reticulocyte count (RBC)
3. Estimation of mean erythrocyte volume (MCV)

When MCV <80fl → iron deficiency anemia (tests recommended)
• measurement of iron, ferritin, TIBC, transferrin
• Hb electrophoresis (haemoglobin diseases)

When MCV 90-100fl →renal failure, infections: (EBV, CMV, HIV), myelofibrosis

When MCV >100fl → lack of B12, folic acid, myelodysplastic syndrome (MDS), hypothyroidism, alcoholism, drugs

What is the treatment for anemia?

Management of anemia depends on treating the underlying causes that caused it.

Iron deficiency anemia, oral or intravenous iron administration is recommended. Oral iron is the most common method of iron supplementation. The dose depends on the person’s age, the calculation of the iron deficiency, the speed of replenishment and the patient’s tolerance of possible side effects. The most common side effects are metallic taste or epigastralgia or diarrhea or constipation. Hemoglobin is usually restored in 6-8 weeks from the start of treatment.
Intravenous iron (IV) may be beneficial in patients who require rapid restoration of hemoglobin levels or in patients who are intolerant to oral iron.

Anemia due to nutritional deficienciesadministration of iron, vit B12 and folic acid is recommended.

Anemia due to chronic diseasesuch as anemia of chronic renal failure, in which the anemia responds to administration of erythropoietin (EPO).

Anemia due to increased destruction of red blood cells such as
• hemolytic anemia due to drugs> stop the drugs
• resistant autoimmune hemolytic anemia > splenectomy
• hemoglobinopathies > blood transfusions

Side effects

If anemia is not diagnosed and treated in time it can cause many and serious problems in all ages. Severe anemia at a young age can lead to cognitive, intellectual, developmental disorders that are often medically unmanageable.
People with nutritional-type anemias should be trained to eat iron-rich foods or consume foods fortified with B12 (certain plants and soy products).
People who have undergone gastric bypass may develop B12 and folate deficiency due to malabsorption in the terminal ileum for whom restorative therapy is recommended.