The most common types of anaemia are
- Iron deficiency anaemia
- Aplastic anaemia
- Haemolytic anaemia
- Sickle cell anaemia
- Pernicious anaemia
- Fanconi anaemia
Iron Deficiency Anaemia
The most common form of anaemia is iron deficiency anaemia which is usually due to chronic blood loss caused by excessive menstruation. Increased demands for iron, such as foetal growth in pregnancy, and children undergoing rapid growth spurts in infancy and adolescence, can also cause iron deficiency anaemia.
This condition is treated with iron supplementation as well as the treatment of the underlying cause of the iron deficiency.
Iron deficiency occurs when the rate of loss or use of iron is more than its rate of absorption and use. The reasons for this are
Chronic blood loss: Most commonly due to excessive menstruation or bleeding into or from the gut as a result of a peptic ulcer, gastritis, haemorrhoids or in children, worm infestation.
Increased use of iron: In pregnancy, due to the growth of the foetus or children undergoing rapid growth spurts in infancy and adolescence.
Decreased absorption of iron
Signs and symptoms
The most common symptoms of chronic anaemia include tiredness, weakness, shortness of breath and sometimes, a fast heartbeat. The tongue may also become smooth, shiny and inflamed - this is called glossitis. Angular stomatitis (erosion, tenderness and swelling at the corners of the mouth) may also occur. In some instances, the patient also suffers from pica, a craving for strange foods such as starch, ice and clay.
The symptoms of the underlying cause of the iron deficiency may be present such as heavy menstrual bleeding or abdominal pain due to peptic ulceration.
Treatment for iron-deficiency anaemia will depend on the cause and severity of the condition. Treatments may include dietary changes and supplements, medicines, and surgery. Severe iron-deficiency anaemia may require treatment in hospital, blood transfusions, iron rejections, or intravenous iron therapy.
Infants and young children, women, and adults who have internal bleeding are at highest risk for iron-deficiency anaemia.
Aplastic anaemia is a blood disorder in which the body's bone marrow doesn't make enough new blood cells. This may result in a number of health problems including arrhythmias, an enlarged heart, heart failure, infections and bleeding.
Aplastic anaemia is a rare but serious condition. It can develop suddenly or slowly and tends to worsen with time, unless the cause is found and treated.
Damage to the bone marrow's stem cells causes aplastic anaemia. In more than half of people who have aplastic anaemia, the cause of the disorder is unknown.
A number of acquired diseases, conditions, and factors can cause aplastic anaemia including
- Toxins, such as pesticides, arsenic, and benzene
- Radiation and chemotherapy
- Medicines such as chloramphenicol
- Infectious diseases such as hepatitis, Epstein-Barr virus, cytomegalovirus, parvovirus B19, and HIV
- Autoimmune disorders such as lupus and rheumatoid arthritis
Inherited conditions, such as Fanconi anaemia, Shwachman-Diamond syndrome, dyskeratosis congenital and Diamond-Blackfan anaemia may also cause aplastic anaemia.
Signs and symptoms
The most common symptoms of aplastic anaemia are
- Shortness of breath
- Coldness in your hands or feet
- Pale skin, gums and nail beds
- Chest pains
Treatment for aplastic anaemia includes blood transfusions, blood and marrow stem cell transplants, and medication. These treatments can prevent or limit complications, relieve symptoms, and improve quality of life.
In some cases, a cure may be possible. Blood and marrow stem cell transplants may cure the disorder. Removing a known cause of aplastic anaemia, such as exposure to a toxin, may also cure the condition.
People of all ages can get aplastic anaemia. However, it is most common in adolescents, young adults and the elderly. Men and women are equally likely to have it.
A person's risk for aplastic anaemia is higher if you have
- Been exposed to toxins
- Taken certain medicines or had radiation or chemotherapy treatment
- Certain infectious diseases, autoimmune disorders, or inherited conditions
Haemolytic anaemia is a condition in which red blood cells are destroyed and removed from the bloodstream before their normal lifespan is up. A number of diseases, conditions and factors can cause the body to destroy its red blood cells. Haemolytic anaemia can lead to various health problems such as fatigue, pain, arrhythmias, an enlarged heart and heart failure.
There are many types of haemolytic anaemias – some of which are inherited and others that are acquired.
Inherited haemolytic anaemias include
- Sickle cell anaemia
- Hereditary spherocytosis
- Hereditary elliptocytosis
- Glucose-6-phosphate dehydrogenase (G6PD) deficiency
- Pyruvate kinase deficiency
Acquired haemolytic anaemias include
- Immune haemolytic anaemia
- Autoimmune haemolytic anaemia
- Alloimmune haemolytic anaemia
- Drug-induced haemolytic anaemia
- Mechanical haemolytic anaemias
- Paroxysmal nocturnal haemoglobinuria
- Certain infections and substances can also damage red blood cells and lead to haemolytic anaemia
The immediate cause of haemolytic anaemia is the early destruction of red blood cells. A number of diseases, conditions, and factors can cause the body to destroy its red blood cells. These causes can be inherited or acquired. Sometimes, the cause of haemolytic anaemia isn't known.
- In inherited haemolytic anaemias, the genes that control how red blood cells are made are faulty. Different types of faulty genes account for the different types of inherited haemolytic anaemias. In each type of inherited haemolytic anaemia, the body makes abnormal red blood cells. The problem with the red blood cells may involve the haemoglobin, cell membrane, or enzymes that maintain healthy red blood cells.
- In acquired haemolytic anaemias, the body makes normal red blood cells, however, some disease, condition, or factor destroys the cells too early. Examples include immune disorders, infections and reactions to medicines or blood transfusions.
Signs and Symptoms
The most common symptom of all types of anaemia is fatigue. A low red blood cell count can also cause shortness of breath, dizziness, headache, coldness in your hands or feet, pale skin, gums and nail beds, as well as chest pain.
Symptoms of haemolytic anaemia include
- Pain in the upper abdomen
- Leg ulcers and pain
- A severe reaction to a blood transfusion
Treatments for haemolytic anaemia include blood transfusions, medicines, plasmapheresis, surgery, blood and marrow stem cell transplants and lifestyle changes.
People who have mild haemolytic anaemia may not need treatment, as long as the condition doesn't worsen. People with severe haemolytic anaemia usually need ongoing treatment.
Haemolytic anaemia can affect people of all ages, races and sexes.
Thalassaemias are inherited blood disorders which cause the body to make fewer healthy red blood cells and less haemoglobin (an iron-rich protein in red blood cells).
The two major types of thalassaemia are alpha- and beta thalassaemia. The most severe form of alpha thalassaemia is known as alpha thalassaemia major or hydrops fetalis, while the severe form of beta thalassaemia is known as thalassaemia major or Cooley's anaemia.
Thalassaemias affect both males and females and occur most often in people of Italian, Greek, Middle Eastern, Asian, and African descent. Severe forms are usually diagnosed in early childhood and are lifelong conditions.
Haemoglobin in red blood cells has two kinds of protein chains: alpha globin and beta globin. If your body doesn't make enough of these protein chains, red blood cells don't form properly and can't carry enough oxygen.
Genes control how the body makes haemoglobin protein chains. When these genes are missing or altered, thalassaemias occur.
Thalassaemias are inherited disorders – they are passed on from parents to their children through genes. People who get abnormal haemoglobin genes from one parent but normal genes from the other are carriers. Carriers often have no signs of illness other than mild anaemia. However, they can pass the abnormal genes on to their children.
Signs and symptoms
Symptoms of thalassaemias are caused by a lack of oxygen in the blood stream. This occurs because the body doesn't make enough healthy red blood cells and haemoglobin. The severity of symptoms depends on the severity of the disorder:
- People who have alpha or beta thalassaemia can have mild anaemia, which can make you feel tired.
- People with beta thalassaemia intermedia have mild to moderate anaemia. They may also have other health problems including: slowed growth and delayed puberty; bone problems; and an enlarged spleen.
- People with haemoglobin H disease or beta thalassaemia major have severe thalassaemia. Symptoms occur within the first two years of life and include severe anaemia and other serious health problems
- Pale and listless appearance
- Poor appetite
- Dark urine
- Slowed growth and delayed puberty
- Enlarged spleen, liver and heart
- Bone problems
Treatment for thalassaemias depends on the type and severity of the disorder. People who are carriers or who have alpha or beta thalassaemia need little or no treatment.
Three standard treatments are used to treat moderate and severe forms of thalassaemia, these include blood transfusions, iron chelation therapy, and folic acid supplements.
Family history and ancestry are the two risk factors for thalassaemias.
Sickle Cell Anaemia
Sickle cell anaemia is a serious disease in which the body makes sickle-shaped ("C"-shaped) red blood cells. Normal red blood cells are disk-shaped and move easily through your blood vessels. Red blood cells contain the protein haemoglobin (an iron-rich protein that gives blood its red colour and carries oxygen from the lungs to the rest of the body).
Sickle cells contain abnormal haemoglobin that causes the cells to have a sickle shape, which don’t move easily through the blood vessels – they are stiff and sticky and tend to form clumps and get stuck in the blood vessels.
The clumps of sickle cells block blood flow in the blood vessels that lead to the limbs and organs. Blocked blood vessels can cause pain, serious infections, and organ damage.
In sickle cell anaemia, a lower-than-normal number of red blood cells occurs because sickle cells don't last very long. Sickle cells usually die after about 10 to 20 days and the body can't reproduce red blood cells fast enough to replace the dying ones, which causes anaemia.
Sickle cell anaemia is an inherited, lifelong disease. People who have the disease inherit two copies of the sickle cell gene – one from each parent.
Signs and Symptoms
The most common symptoms of sickle cell anaemia are linked to anaemia and pain.
Common symptoms for anaemia include
- Shortness of breath
- Coldness in the hands and feet
- Pale skin
- Chest pain
Sudden pain throughout the body is a common symptom of sickle cell anaemia. This pain is called a "sickle cell crisis", and often affects the bones, lungs, abdomen, and joints.
Sickle cell anaemia has no widely-available cure. However, treatments can help relieve symptoms and treat complications. The goals of treating sickle cell anaemia are to relieve pain, prevent infections, eye damage and strokes, and control complications.
Bone marrow transplants may offer a cure in a small number of sickle cell anaemia cases.
Sickle cell anaemia is most common in people whose families descended from Africa, South or Central American, Caribbean islands, Mediterranean countries, India and Saudi Arabia.
Pernicious anaemia is a condition in which the body can't make enough healthy red blood cells because it doesn't have enough vitamin B12 (a nutrient found in certain foods). People who have pernicious anaemia can't absorb enough vitamin B12 due to a lack of intrinsic factor (a protein made in the stomach). However, other conditions and factors can also cause vitamin B12 deficiency.
- A lack of intrinsic factor is a common cause of pernicious anaemia as the body can't absorb enough vitamin B12.
- Some pernicious anaemia occurs because the body's small intestine can't properly absorb vitamin B12 which may be due to the wrong bacteria in the small intestines; certain diseases that interfere with vitamin B12 absorption; certain medicines; surgical removal of part of the small intestine; and tapeworm infection.
- Sometimes people develop pernicious anaemia because they don't get enough vitamin B12 in their diets.
Signs and symptoms
Apart from the symptoms of anaemia (fatigue, dizziness, etc.), the vitamin B12 deficiency may also have some serious symptoms such as
- Nerve damage
- Neurological problems such as confusion, dementia, depression, and memory loss.
- Symptoms in the digestive tract include nausea and vomiting, heartburn, abdominal bloating and gas, constipation or diarrhoea, loss of appetite, and weight loss.
- An enlarged liver
- A smooth, beefy red tongue
- Infants who have vitamin B12 deficiency may have poor reflexes or unusual movements, such as face tremors.
Pernicious anaemia is treated by replacing the missing vitamin B12 in the body. People who have this disease may need lifelong treatment.
You are at higher risk for pernicious anaemia if you
- Have a family history of the condition.
- Have had part or all of your stomach removed.
- Have certain autoimmune disorders that involve the endocrine glands, such as Addison's disease, type 1 diabetes, Graves' disease, and vitiligo.
- Have had part or all of your small intestine removed.
- Have certain intestinal diseases or disorders that prevent your body from properly absorbing vitamin B12.
- Take medicines that prevent your body from properly absorbing vitamin B12.
- Are a strict vegetarian who doesn't eat any animal or diary products and doesn’t take a vitamin B12 supplement, or if you eat poorly overall.
Fanconi anaemia, or FA, is a rare, inherited blood disorder that leads to bone marrow failure. FA is a type of aplastic anaemia that prevents your bone marrow from making enough new blood cells for your body to work normally. FA can also cause your bone marrow to make many abnormal blood cells. This can lead to serious health problems, such as leukemia.
FA is a blood disorder, but it can also affect many of the body's organs, tissues, and systems. Children who inherit FA are at higher risk of being born with birth defects, and people who have FA are at higher risk of some cancers and other serious health problems.
FA is an unpredictable disease. The average lifespan for people with FA is between 20 and 30 years. The most common causes of death related to FA are bone marrow failure, leukemia, and solid tumours.
FA is an inherited disease – it is passed on from parents to children through the genes. At least 13 faulty genes are associated with FA. FA develops when both parents pass the same faulty FA gene to their child. People who have only one faulty gene are FA carriers which means they don't have FA, but they can pass the faulty gene to their children.
Signs and symptoms
The symptoms of FA include
- Bone marrow failure
- Birth defects
- Developmental or eating problems
Treatment for FA is based on a person's age and how well or poorly the person's bone marrow makes new blood cells.
The four main types of treatment for FA are
- Blood and marrow stem cell transplant
- Androgen therapy
- Synthetic growth factors
- Gene therapy
FA occurs in all racial and ethnic groups and affects men and women equally. You are at an increased risk of developing the disease if you have a family history of FA.
Reviewed by Drs Natasha Sewpersad and Yasmin Goga, Inkosi Albert Luthuli Central Hospital, and Sunil Soni, Chairperson: South African Thalassaemia Association, June 2010