The 7 types of anemia

The most common types of anemia are:

  1. Iron deficiency anemia
  2. Aplastic anemia
  3. Haemolytic anemia
  4. Thalassemia
  5. Sickle cell anemia
  6. Pernicious anemia
  7. Farconi anemia
  1. Iron deficiency anemia The most common type of anemia is the iron deficiency anemia, which, usually, is due to poor diet and chronic blood loss during menometrorrhagia (heavy and prolonged menstrual periods). Furthermore, iron deficiency anemia may be caused from increased iron demand for fetus development during pregnancy and rapid developing children in childhood and adolescence.

Causes Iron deficiency occurs when the rate of iron loss or absorption exceeds the rate of iron intake from our diet. Chronic blood loss: Menometrorrhagia or blood loss within the body or the intestine, such as peptic ulcer, gastritis or hemorrhoids are the most common cases of chronic blood loss.

Treatment Treatment depends on the cause and the severity of each case of iron deficiency anemia. It may include dietary changes and supplements, medicines and surgery. Severe cases may lead to hospitalization, blood transfusion, iron reduction (chelation therapy) or intravenous iron treatment (iron infusion).

  1. Aplastic anemia Aplastic anemia is a form of bone marrow failure which cannot produce blood cells in sufficient numbers.  This may lead to a series of health disorders such as arrhythmias, abnormal enlargement of the heart (megalocardia), heart failure, infections and hemorrhage. Aplastic anemia is a rare but severe disease.  It can develop either suddenly or slowly and tends to worsen over time, unless the cause is identified and treated early.

Causes In aplastic anemia, stem cells in the bone marrow are damaged.  In more than half cases of aplastic anemia the definitive cause of the disorder is unknown. A number of acquired diseases and factors may lead to aplastic anemia including toxins such as herbicides, arsenic and benzene, radiation and chemotherapy, drugs such as chloramphenicol, infectious diseases such as hepatitis, Epstein-Barr virus, cytomegalovirus, parvovirus B19 and HIV, autoimmune disorders such as Systemic Lupus Erythematosus (SLE), Rheumatoid arthritis (RA), and some inherited causes.

Treatment The treatment for aplastic anemia includes blood transfusions, blood cells and bone marrow transplants, and medication. These treatment approaches can either prevent or reduce the disease’s complications, reprieve the patients, and improve quality of life.  In more severe cases, a bone marrow transplant, is a potential cure. Avoiding the cause of aplastic anemia, such as exposure to a toxin, can also prevent the occurrence of the disease.

  1. Haemolytic anemia Haemolytic anemia is a disorder in which red blood cells are destroyed and removed from the bloodstream before their normal lifespan. There are a variety of factors that may lead to red blood cells’ destruction in the blood. Haemolytic anemia may result in various health issues such as fatigue, pain, arrhythmias, megalocardia, and heart failure. There are many types of haemolytic anemia some of which are inherited while others acquired.

Causes Haemolytic anemia is the result of red blood cells’ destruction.  There are a variety of factors that may lead to this. These factors are either inherited or acquired.  Sometimes, the definitive cause of haemolytic anemia is unknown. In the inherited cases of the haemolytic anemia, the genes encoding the way of red blood cells’ production, are defective. Different types of defective genes define different forms of inherited haemolytic anemia. Nevertheless, in every type of haemolytic anemia, the body produces abnormal red blood cells. Abnormal red blood cells can affect hemoglobin, cell membrane or enzymes (G-6PD) that maintain red blood cells healthy. In acquired haemolytic anemia, our body produces healthy red blood cells, however, a disease, infection or some other factor, may lead to their early destruction. Some examples include disorders in the immune system, infections and reactions from drugs or blood transfusions.

Treatment Treatment approaches include blood transfusions, drugs, plasmapheresis, surgery, stem cell transplant, and change in lifestyle. Patients with mild haemolytic anemia may not need treatment if the condition does not deteriorate. Patients with severe haemolytic anemia, usually undergo continuous treatment.

  1. Thalassemia Thalassemias are inherited blood disorders characterized by decreased production of healthy red blood cells and hemoglobin (iron-containing protein within the red blood cells). There are two main types of thalassemia: alpha and beta. The most severe form of the alpha thalassemia is known as a-thalassemia or hydrops fetalis, while the most severe form of β-thalassemia is known as thalassemia major or Cooley’s anemia. Thalassemias affect both men and women and is more common in people of Italian, Greek, Middle Eastern (hence its name as Mediterranean anemia), Asian and African descent. Severe forms are diagnosed in early childhood and are lifelong diseases.

Causes Hemoglobin in rood blood cells consists of two types of polypeptide chains: α-globin and β-globin. Should the body does not produce a sufficient number of these chains, the formation of red blood cells is abnormal and therefore, they are unable to carry enough oxygen from the respiratory organs to the rest of the body. Genes contain the information of how these polypeptide chains are formatted. Thalassemias emerge when these genes are altered. Thalassemias are inherited blood disorders that pass from parent(s) to their children when they inherit the defective gene(s). Patients who inherit the defective hemoglobin genes from one parent, but the healthy genes from the other parent, are just carriers of the disease. Thalassemia carriers do not show any symptoms of the disease except from mild anemia. However, they can pass the defective genes to their children.

Treatment Treatment depends on the type and the severity of each case of thalassemia. Carriers or patients with mild a- or b-thalassemia, need minimum or no treatment. For severe cases of thalassemia, treatment includes blood transfusions, iron chelation, and folic acid supplements.

  1. Sickle cell anemia Sickle cell anemia is a severe blood disorder in which the body produces red blood cells in the shape of sickle (“C”). The shape of the normal red blood cells is biconcave, which makes them pass easily through extremely small blood vessels. Red blood cells contain hemoglobin (an iron-containing protein responsible for blood’s red pigment and for carrying the oxygen from the respiratory organs to the rest of the body). Sickle cells contain an abnormal hemoglobin responsible for the cells’ sickle shape and for their inability to pass easily through blood vessel resulting in the block of the blood flow leaving the rest of the body with reduced blood intake. Blocked vessels may result in pain, severe infections and organ damage. The number of sickle blood cells are lower than it should be as sickle cells do not last much: they die after about 10 to 20 days and the body cannot produce fast enough new ones to replace them.

Causes Sickle cell anemia is an inherited, lifelong disease. Patients suffering from sickle cell anemia inherit both copies of the recessive gene responsible for the disease, one from each parent.

Treatment Sickle cell disease does not have a widely available cure. However, treatments can help relieve symptoms and treat complications. The goals of treatment are to relieve pain, prevent infections, ocular damages, strokes and other complications. Bone marrow transplants can offer treatment in a small number of cases of sickle cell anemia.

  1. Pernicious anemia Pernicious anemia is an autoimmune disease in which the body cannot produce healthy red blood cells due to the lack of vitamin Β12. Patients cannot absorb enough Β12 due to the lack or loss of the intrinsic factor (a protein which is produced in the stomach). However, there are other factors that may lead to insufficient Β12 supply.

Causes Lack of the intrinsic factor is a common cause as the body cannot absorb enough Β12.  

Pernicious anemia may emerge because of the intestine’s inability to properly absorb Β12 due to the absence of normal gut flora, and due to several diseases that interfere with Β12’s absorption. Occasionally, individuals may develop pernicious anemia because they do not get enough Β12 from their diet.

Treatment Pernicious anemia is treated by replacing the missing vitamin B12 in the body. People suffering from pernicious anemia may need chronic treatment.

  1. Fanconi anemia Fanconi anemia or FA, is a rare, inherited blood disease associated with the bone marrow’s inability to produce blood cells. FA is a type of aplastic anemia in which the bone marrow is destroyed resulting in the production of less red blood cells. Therefore, the body does not function properly. Additionally, in FA, bone marrow may produce many abnormal blood cells. This may lead to severe health issues such as leukemia. 

Causes FA is an inherited disease. There are at least 13 defective genes associated with FA. The disease occurs when the child inherits both copies of the defective FA genes, one from each parent. Individuals who have only one copy of the FA gene, they do not develop the anemia, however, they may pass the defective gene to their children.

Treatment FA treatment is based on a person’s age and how well or badly a person’s bone marrow produces new blood cells. There are four main treatment approaches for FA:

  • Bone marrow (or stem cells) transplant
  • Androgen administration
  • Hematopoietic synthetic growth factors administration
  • Gene therapy