Anemia

Epidemiology

The most vulnerable groups for anemia are women and young children, especially the ones who are living in developing countries. There are nearly 1,5 billion people affected by this condition of which are approximately 500 million women, 250 million men, 600 million children, and 150 million elderly people. This disorder is followed with a higher risk for morbidity and mortality, reducing the general quality of life and patient’s working ability.

Definition

Anemia is a condition where hemoglobin or erythrocytes levels in the blood are decreased below the normal values. There are many types of anemia, and each one has a different cause. Erythrocytes are red blood cells (RBC) produced in spongy bone’s marrow. Their main function is to transfer the oxygen throughout the blood to all organs and tissues where it could be used in metabolism. The protein which is responsible for oxygen binding is called hemoglobin, without it, blood would be colorless. When a cell uses oxygen for its processes, it converts oxygen (O2) to carbon dioxide (CO2), hemoglobin then collects CO2, and makes an exchange for fresh oxygen in the lungs. If the erythrocytes or hemoglobin levels are low, others organs suffer oxygen insufficiency, and anemia symptoms are shown. There is a difference between relative and absolute anemia. In relative anemia hemoglobin/erythrocyte levels are lowered due to the increased volume of plasma (typically seen in the third trimester of pregnancy), and the absolute is a consequence of lowered erythrocyte mass.

Types

anemia

Anemia is caused by various problems, although it can be a primary disease on itself, anemia often represents a symptom of other disorders. Erythropoiesis is a process of RBC synthesis, and if that process is interrupted/decreased anemia occur. The second reason is the increased loss of RBC on the other hand.

Iron deficiency anemia

This is the most common anemia type in all of the global population. Iron is the crucial constituent of hemoglobin, and without it, hemoglobin couldn’t bind oxygen. The deficiency of iron may be due to chronic blood loss, inadequate iron intake or higher iron demand. Hemorrhage is the main reason for this condition, and it is usually provoked by heavy menstrual bleeding, peptic ulcer, stomach cancer, hemorrhoids or the use of NSAID medicines. Inadequate blood intake is frequently seen in vegans and people with a monotonous diet without iron-rich nutrients. Pregnant women, babies, little children, and adolescents have higher iron demands.

Vitamin deficiency anemia

Erythropoiesis depends on folate (vitamin B9) and cobalamin (vitamin B12). If an organism lacks these vitamins, the production of RBC is inefficient. Important thing is to distinguish which vitamin is responsible for anemia so it can be treated accordingly. Some people have a problem where their digestive system can’t absorb vitamin B12, called pernicious anemia.

Hemolytic anemia

Hemolysis (the destruction of RBC) can be inherited or it can develop later in life. Some drugs, autoimmune processes, and infections like malaria can induce this process.

Sickle cell anemia

This disease is an inherited disease that is characterized by rigid, sickle-like shape erythrocytes prone to hemolysis. Unlike the normal, healthy, round erythrocytes who have Hemoglobin A, sickle-shaped erythrocytes have defected Hemoglobin S which is causing this changing in shape. It’s estimated that 1 out of 400 African descent babies will develop this disease.

Anemia of chronic diseases

Chronic inflammations like rheumatoid arthritis, infections like tuberculosis, or other diseases may lead to inadequate use of iron or production of RBC which can induce this disorder.

Anemia induced by bone marrow diseases

If the bone marrow is infiltrated by malignant or fibrous tissue, it interferes in blood cell production and causes this disorder. Aplastic anemia is a rare, but life-threatening disease where bone marrow stops the production of all blood cells.

Symptoms

Sometimes is very hard to distinguish this disorder from other diseases, because the symptoms are usually non-specific, related to the severity of anemia, time of progression or person’s age. Since the organism doesn’t get oxygen in the amount it is needed to, general symptoms like fatigue, weakness, dizziness, tinnitus, lightheadedness, lack of concentration, insomnia, appetite loss, depression, shortness of breath, paleness of skin, and cold hands and feet are shown. In more severe anemia, heart starts to beat harder and faster trying to provide oxygen to oxygen-deprived tissues which can induce heart failure.

Some symptoms are specific to certain types. Koilonychia represents abnormally thin nails which aren’t convex in shape but are flat or concave. They break up easily and can represent a symptom of iron deficiency. Other symptoms of this disease may include mouth soreness with cracks on the corners. Symptoms of vitamin deficiency anemia are atrophic glossitis (bald tongue), and diarrhea. Deficiency of vitamin B12 is followed by neurological disorders such as a lost sense of touch, tingling sensation in the hands or feet, difficulty walking or even dementia.

Risk factors

Many risk factors may influence a development of this disorder.

  • Diet – Diet that is lacking iron, vitamins B9 and B12 increases the risk of anemia. Vegans and vegetarians need to compensate these nutrients with a diverse diet.
  • Pregnancy – Folate supplements in pregnancy are recommended. Women who don’t take it are in increased risk for anemia.
  • Intestinal problems – Some bacteria, intestinal disorders such as Crohn’s disease and celiac disease or operations done on intestines lower the ability of nutrient absorption which increases the risk of anemia.
  • Menstruation – Heavy menstruation induces the loss of erythrocytes, thus increases the risk of anemia.
  • Alcohol – Alcoholic drinks interfere with the absorption of folate and other vitamins.
  • Medicines – Some drugs like methotrexate for rheumatoid arthritis can cause folate deficiency or an antibiotic called chloramphenicol may cause aplastic anemia.
  • Chronic conditions – Some chronic conditions such as cancer, chronic kidney disease, tuberculosis, AIDS, and hypothyroidism are increasing the risk of anemia.

Complications

This disorder can cause various complications if it’s not treated .

Pregnancy complications – If the fetus doesn’t get enough folate from a mother, deformations of the brain and spinal cord may happen. Premature birth can occur in pregnant women with folate insufficiency.

Tiredness – Anemia can leave you lethargic and fatigued, making you less active and productive, without a motivation.

Immune system – Anemia lowers body’s natural defence increasing the susceptibility to other health problems.

Hearth problems Anemia can cause fast or irregular heartbeat because the body is in lack of oxygen which the heart tries to compensate with pumping more blood leading to enlarged heart or in the worst case, a heart failure.

Diagnosis

diagnosis of anemia

To diagnose this disorder, a doctor will require a full medical history, body examinations, and certain blood tests. Depending on medical history some specific checkups might be needed. With a medical history, the doctor can see the connection between symptoms and possible causes or consequences of anemia as well as to occurrence in the patient’s family. With body examinations, paleness, mouth cracks, tong inflammation or thin nails may be seen and considered as a symptom.

The most important thing in the determination of anemia are the blood tests. Diagnose is set if the value of hemoglobin is below specified levels for certain age, sex, and altitude.

The cut-off values of Hemoglobin for population living in areas with low altitude are:

13 g / dL for men

12 g / dL for non-pregnant women

11 g / dL for pregnant women

11.5 g / dL for children of age between 5 and 11 years

11 g / dL for children of age between 6 months and 5 years

Classification of anemia by Hemoglobin deficiency:

0 None Hemoglobin above cut off values

1 Mild –Hemoglobin values between 9.5 – 11 g / dL

2 Moderate – Hemoglobin values between 8 – 9.5 g / dl

3 Severe – Hemoglobin values between 6.5 – 8 g / dL

4 Life threatening – Hemoglobin values bellow 6.5 g / dL

After confirming the presence of disease, other blood tests are needed to determine what is the cause for anemia, namely etiological type of anemia.

  • Complete blood count gives information about the full count of blood cells, erythrocytes shape, and their Hemoglobin level.
  • Serum iron test and serum ferritin test are showing the available iron in the organism.
  • Folate and vitamin B12  tests which correlate to RBC production.
  • Bilirubin and reticulocyte tests are showing in which amount are erythrocytes renewed. This is important in hemolytic anemia where the RBC are destroyed faster than they are produced.
  • Bone marrow biopsy and aspiration are needed when a doctor is suspecting that bone marrow is damaged or diseased.

Prevention

prevention of anemia

If you are in the risk group for developing this disorder there are some things that you can do to prevent it, although many anemia types aren’t preventable, those relate to nutrition are indeed. Iron is mostly found in food of animal origin, so if you’re a vegetarian, vegan, you lack the iron-rich diet or you have increased demand for iron, iron supplementation can be used.  Vitamin C is important because it helps the body to absorb the iron. If you lack vitamin C, it’s supplementation can be done because it’s a common one, and it is always recommended to take it if you’re using iron supplementation. Vitamin C is found in citruses, parsley, cabbage, tomatoes, and other vegetables. Folate supplementation is important in 3 months before pregnancy, and in the first trimester of the pregnancy. This vitamin is common in legumes, green vegetables, and in fortified cereals. Vitamin B12 is found in food of animal origin, rarely in vegetables, and its supplementation is recommended for vegans.

Treatment

Treatment is etiological, it depends on the cause of the disorder. The goal is to increase the Hemoglobin level, managing the oxygen transportation in blood, thus relieving of symptoms.

Iron deficiency anemia

It is needed to detect and regulate the reason for the iron deficiency if it’s possible. Usually, the oral form of iron preparations is given in it’s ferrous, divalent state which is easier to absorb. Intravenous preparations are given if the oral preparations aren’t acceptable and if the fast compensation for iron is needed. In more severe cases, doctor resolves to blood transfusion.

Vitamin deficiency anemia

This type of anemia is treated depending on the cause of the deficiency. Folate is given in oral preparations and vitamin B12 in muscle injections. If a patient has pernicious anemia, vitamin B12 needs to be given until the end of life.

Hemolytic anemia

Hemolytic anemia is treated according to its cause. Antimalarial medication is needed if the malaria is causing this disease. Autoimmune processes are handled with immunosuppressants. Sometimes avoiding the exposure to factors that are causing hemolysis is enough, but in more severe cases a doctor may resort to plasmapheresis (plasma exchange, blood filtering) or splenectomy (surgical removal of the spleen).

Sickle cell anemia

Antibiotics are often given to prevent pneumonia. A drug named hydroxyurea is a myelosuppressive agent that can be used in sickle cell anemia as it stimulates an alternate form of Hemoglobin (Hemoglobin F) that isn’t susceptible to shape changing. Pain-relieving drugs, blood transfusion, and bone marrow transplantation are sometimes needed.

Anemia of chronic diseases

The treatment is focused on managing the primary disease followed by blood transfusions and the use of synthetic erythropoietin. Erythropoietin is a hormone, normally produced in kidneys. Its function is to stimulate the production of RBC in the bone marrow.

Anemia induced by bone marrow diseases

This type is treated by bone marrow transplantation, chemotherapy for cancer or with use of other medications. Immunosuppressants are occasionally given in Aplastic anemia to keep the immune system from attacking the bone marrow. Blood transfusions can restore blood cell counts, and bone marrow transplantation can help in restoring the blood cell production.

Summary
Article Name
anemia
Description
Anemia is cardiovascular disorder This disorder is followed with a higher risk for morbidity and mortality, reducing the general quality of life and patient’s working ability.
Author
Publisher Name
HOSP