Anemia (Anemia) • Definition, Symptoms & Causes

Anemia (anemia) occurs when there is too little of the blood pigment hemoglobin. Besides tiredness, paleness and difficulty concentrating, which symptoms are also signs of anemia and what are the possible causes?

Typical symptoms of anemia are fatigue, paleness, and headache.
© Getty Images / Oscar Wong

The cause can be both reduced blood formation and an increased breakdown or loss of red blood cells. Anemias can be classified according to their underlying causes or based on the changed blood values.

Ferrous foods: These eleven provide a lot of iron

Ferrous foods: These eleven provide a lot of iron

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Forms of anemia: aplastic, hemolytic and diet-related anemia

Basically, a distinction can be made between acquired and congenital anemia. The most common forms of anemia are:

Iron Deficiency Anemia: It is the most common type of acquired anemia. About 80 percent of all anemias are due to an iron deficiency. In addition to blood loss as a cause, iron deficiency can also occur due to diet.

Renal anemia: Since the kidneys produce a hormone that is important for blood formation, erythropoietin (also called "Epo"), kidney diseases can also lead to anemia, which is known as "renal anemia".

Aplastic anemia: In so-called aplastic anemia, not only is the production of red blood cells reduced or abolished, but the formation of at least two of the three types of blood cells (i.e. red blood cells, white blood cells and / or platelets).

Hemolytic anemia: Examples are spherical cell anemia, sickle cell anemia: symptoms and therapy options and what is known as thalassemia.

Folic Acid Deficiency Anemia: Folic acid is involved in the formation of blood cells, which is why a deficiency can be associated with anemia.

Vitamin B12 Deficiency Anemia: A deficiency in vitamin B12 (cobalamin) can also lead to anemia. In addition to insufficient intake from food, the cause of a cobalamine deficit can also be a deficiency in an important digestive enzyme, the so-called intrinsic factor.

Important blood values ​​for classifying anemia

Important parameters for the classification of anemia are the size of the red blood cells (also MCV or mean cell volume) and their loading with blood pigment (also MCH, mean cell hemoglobin content).

In anemia, both values ​​can be low, normal, or high. The red blood cells can therefore be small, normal or enlarged. They may be lacking in blood pigment (hemoglobin) or they may be excessively loaded with it. A normal load of hemoglobin per erythrocyte also occurs in anemia.

Symptoms of anemia: These signs suggest anemia

In all forms of anemia, the transport of oxygen is disturbed. That is why the basic symptoms are often the same: skin and mucous membranes are pale, those affected feel easily exhausted, suffer from poor concentration and headaches. Some patients also report shortness of breath during exertion or an increased heart rate even at rest.

Many people have the onset of iron deficiency anemia without noticing any symptoms. You will only become aware of this through a routine blood test. Pronounced anemia, on the other hand, can lead to shortness of breath or rapid pulse acceleration even during light physical activity.

Inflammation of the skin and mucous membranes in iron deficiency anemia

In the case of iron deficiency, inflammation of the skin and mucous membranes can also occur. Torn corners of the mouth, brittle nails, hair loss, dry skin, occasionally with itching, and difficulty swallowing (when the esophagus is inflamed) can occur. Some of the patients also experience abnormal cravings, for example on lime or earth.

Yellowing and gallstones in hemolytic anemia

In addition to the typical side effects of anemia, patients with hemolytic anemias, for example spheroid cell anemia, sickle cell disease or thalassemia, also show signs of increased blood breakdown. Since the breakdown of blood cells takes place in the spleen, it is usually enlarged. A breakdown product is the so-called bilirubin. If more bilirubin is produced than the body can excrete, it is deposited in the body.

As a result, the skin and mucous membranes can turn yellow; the first thing that is usually affected is the white skin of the eye (sclera). The yellow color is also called jaundice. In addition, gallstones can form due to the accumulation of bilirubin, which can cause severe pain if the bile drainage ducts are blocked.

Bone pain and organ damage in sickle cell anemia

In some European countries, all infants are examined after birth to determine whether they have sickle cell disease (so-called neonatal screening). In Germany there has not yet been such a serial examination for this clinical picture. Therefore, the diagnosis is usually made more or less randomly in childhood. If the symptoms are not so pronounced or if those affected do not see a doctor until late, it can also happen that the diagnosis is only made in adulthood.

When the red blood cells deform into sickle cells, they can block small blood vessels. As a result, the oxygen supply to the tissue is interrupted. Bone pain and organ damage are typical. The spleen loses its defense function in the first year of life. For this reason, patients with sickle cell disease are very susceptible to infection.

Infections and developmental disorders in thalassemia

The severe form of thalassemia, the so-called thalassemia major, also becomes symptomatic in early childhood: attacks of fever, infections and developmental disorders occur.

Neurological symptoms in vitamin B-12 deficiency anemia

The (now rare) full picture of pernicious anemia, a special form of vitamin B12 deficiency anemia, includes neurological symptoms in addition to the symptoms typical of all forms of anemia and frequently existing gastric mucosal inflammation. These include muscle weakness, unsteady gait as well as painful or tingling sensations in the hands and feet up to paralysis. These additional neurological symptoms do not arise in anemia caused by folic acid deficiency.

If the symptoms mentioned are present, it should be examined whether one of the above-mentioned forms of anemia is present.

Anemia triggers: causes of the various forms of anemia

Iron deficiency anemia due to blood loss

In this country, the cause of an iron deficiency with foods containing iron is usually a loss of iron due to blood loss. Bleeding in the digestive tract is responsible for slightly more than half of all iron deficiency anemias. In the digestive system, such bleeding is usually not noticed by the affected person.

High blood loss can occur with:

Taking painkillers also plays a role in iron deficiency anemia in this country, as these can promote the formation of ulcers. These and other acquired anemias can also appear as a side effect of other diseases, such as infectious diseases or cancer.

Diet-related iron deficiency anemia

Especially in underdeveloped countries, but also in this country, a reduced intake of iron due to malnutrition or malnutrition also plays an equally important role in iron deficiency. Eating disorders such as anorexia nervosa: deadly compulsion to starve and bulimia: out of the eating and vomiting addiction lead to disruptions in the iron supply. The iron requirement is also increased during pregnancy and breastfeeding as well as during growth.

Vitamin B-12 and folic acid deficiency anemia

If the body is insufficiently supplied with vitamin B12: deficiency symptoms with these foods and / or provided with folic acid, the production of red blood cells in the bone marrow will be disrupted. Immature, relatively large cells that have too much hemoglobin loaded and have a shortened lifespan are released into the bloodstream.

Reasons for the insufficient supply of vitamin B12 can be a strictly vegan diet or alcohol abuse. Vitamin B12 deficiency anemia can also occur when an important protein for digestion, the so-called intrinsic factor, is missing. Then doctors speak of pernicious anemia.

In industrialized nations, an inadequate supply of folic acid through diet is rare. In addition to alcoholism, the use of medication and various diseases can lead to a folic acid deficiency, which disrupts blood formation.

Myelodysplastic Syndrome (MDS): In myelodysplastic syndrome (MDS), pathological changes in bone marrow cells acquired in the course of life (due to genetic predisposition or environmental influences) lead to an inundation of the body with immature and functionless blood cells, and normal blood production takes place only to a very limited extent.

Hereditary hemolytic anemia

Hemolytic anemias are forms of anemia that are based on an increased breakdown of blood cells (hemolysis), which is why the lifespan of the erythrocytes is shortened.

Thalassemia: An example of anemia that is based on both impaired blood production and increased blood breakdown is thalassemia. This is the generic term for hereditary diseases that are common among people from the Mediterranean region and that are associated with a disruption in blood pigment production. This leads to hypochromic anemia (the red blood cells therefore lack pigment) and increased hemolysis, i.e. an increased breakdown of the red blood cells.

Ball cell anemia: Globular cell anemia or hereditary spherocytosis is the most common type of hemolytic anemia. In Germany there are around 33,000 patients with spheroidal cell anemia. The clinical picture is based on defects in the erythrocyte wall due to a genetic defect. The red blood cells lose their malleability and are broken down more quickly in the spleen.

Sickle cell anemia: In contrast, in sickle cell anemia, which is also congenital, the bone marrow produces a defective blood pigment. This causes the erythrocytes to deform like a sickle when there is a lack of oxygen and thus clog blood vessels.

Anemia Diagnosis: How Does My Doctor Determine Anemia?

Anemia will usually be determined by a doctor with a blood test. When talking to the patient, the doctor should ask about other complaints.

Around 70 percent of the iron in the blood is found in hemoglobin, the red blood pigment responsible for transporting oxygen. Routine blood tests determine the number of red blood cells and the amount of hemoglobin. If the values ​​are low, this indicates a latent iron deficiency anemia.

The two decisive blood values ​​for the diagnosis of anemia are the blood pigment and the proportion of cells in the blood volume, the so-called hematocrit. Both values ​​are naturally somewhat lower in women than in men. Anemia is present if the hemoglobin value falls below 12 grams (g) / deciliter (dl) in women or below 13 g / dl in men, or if the hematocrit is less than 38 percent in women or less than 42 percent in men. Other limit values ​​apply in childhood.

Affected patients may be paleness and may complain of fatigue. The doctor should ask about other complaints and previous illnesses of the patient himself and his family. A thorough physical exam will also help make the correct diagnosis.

The anemia can be narrowed down more precisely on the basis of other blood values ​​such as the size and the dye content of the red blood cells. Anemia, in which the red blood cells are small and carry little dye (ie "microcytic hypochromic anemia"), can hide, for example, iron deficiency anemia or thalassemia.

What type of anemia is it?

If the erythrocytes are normal in size and loaded with a normal amount of hemoglobin ("normocytic normochromic anemia"), it could be a hemolytic anemia, an acute bleeding anemia, an aplastic or a renal anemia. If the red blood cells are large and loaded with a lot of blood pigment ("macrocytic hyperchromic anemia"), this could be due to a lack of vitamin B12 or folic acid.

In order to detect an iron deficiency, among other things, the iron storage protein, the so-called ferritin, is determined. If there is a lack of iron, its concentration in the blood is reduced. If a low iron level is found, a possible source of bleeding must be searched for.

For example, to differentiate hemolytic anemias from aplastic or renal anemias, one counts the precursor cells of the red blood cells, the so-called reticulocytes. If blood formation is disturbed, for example in aplastic anemia or because the blood formation hormone produced in the kidney is missing, there are few precursor cells in the blood. If, on the other hand, the bone marrow is intact and it tries to counteract an increased breakdown of blood cells (hemolysis) with an increased formation of red blood cells, the reticulocytes are increased. Other signs of hemolysis are the increased accumulation of breakdown products such as bilirubin in the blood.

In addition, the typical pathological forms of red blood cells can be seen under the microscope: In sickle cell anemia: Symptoms and therapy options are deformed sickle-shaped when the seal is airtight, in thalassemia they can act like shooting targets, and in spherical cell anemia they sometimes actually look spherical. If sickle cell disease or thalassemia is suspected, the laboratory must follow up with a hemoglobin analysis. Special examination methods can also make the typical membrane defects of the spherical cells visible.

A deficiency in other nutrients and vitamins such as vitamin B12 and folic acid: If there is a deficiency during pregnancy, there is a risk of severe deformities, which can also be detected by blood tests.

Treatment of anemia

The therapy varies depending on the cause of the anemia. Iron deficiency can be compensated for by appropriate medication and a balanced diet; in the case of hereditary anemia, the administration of blood products, pain medication or a stem cell transplant may be appropriate.

Basically there are causal and symptomatic therapeutic approaches. In anemia caused by bleeding in the digestive tract, hemostasis is of course the first, causal therapeutic measure. In addition, blood can be given. If there is an iron deficiency due to the bleeding, this is compensated with iron tablets. As a therapy, iron is administered as bivalent iron in tablet form or as juice.

However, many patients react with gastrointestinal disorders, so a maximum daily dose of 100 milligrams and taking with or just before meals are recommended. The therapy must be carried out over a period of at least six weeks to ensure that the iron stores in the body are reliably replenished. The success should be checked by laboratory tests. The typical black coloration of the stool when taking iron tablets is no cause for concern.

And: The consumption of black tea during therapy significantly reduces iron absorption. If an iron or other nutrient deficiency is due to a poor diet or eating disorders, the change in eating habits is again a causal treatment.

Stem cell transplant and blood transfusion

There is no causal therapy for many of the more complex forms of anemia. Hereditary diseases in particular cannot be treated causally, as they are based on a genetic defect that cannot (yet) be remedied.

A curative treatment option for thalassemia, sickle cell disease and aplastic anemia is stem cell transplantation: bone marrow from the donor. A relative donates stem cells from blood or bone marrow to the patient. These implant themselves in the recipient's bone marrow, where they ensure the formation of healthy blood cells.

For this, however, certain requirements must be met, in particular genetic compatibility ("tolerance") of donor and recipient so that there are no rejection reactions.

In the case of hemolytic forms of anemia, the administration of blood reserves can be considered as symptomatic treatment. Regular transfusions (about every three weeks) are usually indispensable, particularly in the severe form of thalassemia.

Due to the large amount of blood in reserve, however, the organism is overloaded with iron. For this purpose, so-called iron elimination therapy is indicated, which can also have side effects.

The typical pain crises in patients with sickle cell anemia can be treated with painkillers of different strengths, depending on the severity.

In the case of spheroidal cell anemia, it has proven useful to surgically remove the spleen, which is already functionless at an early stage. This normalizes the lifespan of the erythrocytes, even if the membrane defect and spherical shape are retained. The hemoglobin concentration and reticulocyte count are completely normalized; that is, the anemia is cleared. However, the spleen should not be removed before the age of six. In addition, the lifelong increased risk of infection for those affected must be taken into account. Anemia: forms, causes, and symptoms of anemia

Patients with aplastic anemia require transfusions of the affected blood cells, i.e., if necessary, preserved red blood cells and / or blood platelets (thrombocytes). If possible, a stem cell transplant should be done. Without any treatment, the disease is fatal in seven out of ten cases in adulthood. For comparison: ten years after a stem cell donation from relatives, up to eight out of ten patients are healthy again. If a compatible donor cannot be found, immunosuppressive drugs are another treatment option.

Pernicious anemia can be treated with vitamin B12. To do this, the patient is given an injection into the muscle initially once a week, then every six months. A folic acid deficiency can be compensated with the help of tablets.

Blood count: important values ​​and what they mean

Blood count: important values ​​and what they mean

Anemia prevention: can anemia be prevented?

Serious iron deficiency is rare in industrialized countries. However, food containing iron should be taken into account during growth, pregnancy or heavy menstrual periods. After all, a balanced diet is the best way to prevent iron deficiency anemia.

This also applies to vegetarians: although plant-based food contains a lot of iron, the high phosphate content prevents it from being readily available to the body. Legumes, rye and lettuce should therefore have a permanent place in the menu. The organism absorbs iron from foods of animal origin much more easily.

Iron in Pregnancy

In Europe, around every tenth woman of childbearing age suffers from iron deficiency anemia. In developing countries, more than half of women are affected. Every fourth person worldwide has an iron deficiency. However, food containing iron should be taken into account during growth, pregnancy or heavy menstrual periods. Pregnant women, premature babies and newborns who weigh less than 2,500 grams are now given prophylactic iron.

For patients with hemolytic anemia, protection against infectious diseases plays a central role in prevention, as the spleen usually loses its defense function as the disease progresses. For this reason, vaccinations are particularly important in children with spheroidal cell disease, sickle cell disease or thalassemia, especially against pneumococci, Haemophilus influenzae and meningococci.

Also rubella: harmless, but dangerous during pregnancy are feared. An infection with the so-called parvovirus B19 can trigger an aplastic crisis, i.e. cause the formation of red and white blood cells and platelets to dry up. Patients who have not yet had rubella should therefore avoid contact with sick people.

Lifelong antibiotic prophylaxis is recommended after removal of the spleen, for example in the case of globular cell anemia. Studies are currently investigating the possibility of not completely removing the spleen, but of leaving an active residue in the patient's body and thus shortening the long-term administration of antibiotics.

Parents of Infants and Young Children with Sickle Cell Anemia: Symptoms and Treatment Options should learn to feel their children's spleen. Usually the spleen is hidden under the left costal arch and cannot be felt at all. If it is palpable, this indicates an enlargement.

If the spleen suddenly becomes larger in sickle cell disease, it can be caused by a life-threatening condition called "spleen sequestration". Almost all of the blood that is supposed to flow through the body is retained in the spleen. As it is no longer available for the circulatory system, it comes to a state of shock with a rapid heartbeat, low blood pressure and extreme paleness.

Spleen sequestration can develop very quickly and be fatal. At the beginning, the child often complains of stomach ache, becomes pale and limp and does not want to eat anymore. Sometimes a fever also occurs. Every sickle cell patient with abdominal pain should therefore be presented to a doctor. In the case of spleen sequestration, transfusions, but also immediate surgical removal of the spleen, may be indicated.

In patients with sickle cell anemia, annual ultrasound checks of the large brain-supplying vessels can also be useful in order to detect an impending infarction of the brain tissue in good time. If there is an increased risk, transfusion treatment may be necessary.

Furthermore, patients with sickle cell disease should ensure that they drink enough fluids and avoid alcohol, cigarettes and other factors that trigger a crisis (e.g. hypothermia).