Sickle Cell Anaemia
Sickle cell disease is the name for a group of inherited health conditions that affect the red blood cells. The most serious type is called sickle cell anaemia. It is not a type of Cancer.
Sickle cell disease is particularly common in people with an African or Caribbean family background.
People with sickle cell disease produce unusually shaped red blood cells that can cause problems because they do not live as long as healthy blood cells and can block blood vessels.
Sickle cell disease is a serious and lifelong health condition, although treatment can help manage many of the symptoms.
Sickle cell disease can cause a wide range of symptoms.
These can start from a few months of age, although many children have few or no symptoms if treatment is started early on.
The main symptoms are:
- painful episodes
- getting infections often
- anaemia
Painful episodes
Episodes of pain known as sickle cell crises are one of the most common and distressing symptoms of sickle cell disease.
They happen when blood vessels to part of the body become blocked.
The pain can be severe and lasts for up to 7 days on average.
A sickle cell crisis often affects a particular part of the body, such as the:
- hands or feet (particularly in young children)
- ribs and breastbone
- spine
- pelvis
- tummy
- legs and arms
How often someone with sickle cell disease gets episodes of pain varies a lot.
Some people may have one every few weeks, while others may have less than 1 a year. The average is 1 bad episode a year.
It’s not always clear what triggers bad pain, but sometimes painful episodes can be caused by the weather (such as wind, rain or cold), dehydration, stress or strenuous exercise.
Infections
People with sickle cell disease are more vulnerable to infections, particularly when they’re young.
Infections can range from mild, such as colds, to much more serious and potentially life threatening, such as meningitis.
Vaccinations and daily doses of antibiotics can help reduce the risk of many infections.
Anaemia
Nearly all people with sickle cell disease have anaemia, where the haemoglobin in the blood is low.
Haemoglobin is the substance found in red blood cells that’s used to transport oxygen around the body.
This does not usually cause many symptoms, but sometimes it can get worse if you become infected with the virus that causes slapped cheek syndrome (parvovirus).
This can lead to a sudden drop in the number of red blood cells and may cause additional symptoms, such as headaches, a rapid heartbeat, dizziness and fainting.
It’s usually treated with a blood transfusion.
Other problems
Sickle cell disease can also sometimes cause a wide range of other problems.
These include:
- delayed growth during childhood and delayed puberty
- gallstones, which can cause tummy aches and yellow skin and eyes (jaundice)
- bone and joint pain
- a persistent and painful erection of the penis (priapism), which can sometimes last several hours
- painful open sores on the lower legs ( leg ulcers)
- Strokes or transient ischaemic attacks, where the flow of blood to the brain is blocked or interrupted
- a serious lung condition called acute chest syndrome, which can cause a fever, cough, chest pain and breathing difficulties
- swelling of the spleen, which can cause shortness of breath, a rapid heartbeat, tummy pain, a swollen tummy and anaemia
- blurred or patchy vision, reduced night vision and occasionally sudden vision loss,
- high blood pressure in the blood vessels that carry blood from the heart to the lungs (pulmonary hypertension)Kidney or urinary problems, including blood in the urine and bedwetting
Sickle cell disease is caused by inheriting the sickle cell gene.
It’s not caused by anything the parents did before or during the pregnancy and you cannot catch it from someone who has it.
How sickle cell disease affects the body
Your genes are the set of instructions found inside every cell in your body. They determine characteristics like the colour of your eyes and hair.
People with sickle cell disease do not make haemoglobin properly. Haemoglobin is a substance in red blood cells, which carry oxygen around the body.
Normal red blood cells are flexible and disc-shaped, but in sickle cell disease they can become rigid and shaped like a crescent or sickle because the haemoglobin inside them clumps together.
These unusual cells do not live as long as normal red blood cells and can become stuck in blood vessels.
Diagnosis
Sickle cell disease is usually detected during pregnancy or soon after birth.
Blood tests can also be carried out at any time to check for the condition or to see if you’re a sickle cell carrier and are at risk of having a child with the condition.
Sickle cell screening during pregnancy
Screening to check if a baby’s at risk of being born with sickle cell disease is offered to all pregnant women in England.
In parts of England where sickle cell disease is more common, pregnant women are offered a blood test to check if they carry sickle cell.
In areas where sickle cell disease is less common, a questionnaire about your family origins is used to work out whether you should have a blood test for sickle cell.
You can also ask to have the blood test even if your family origins do not suggest your baby would be at high risk of sickle cell disease.
Screening should ideally be carried out before you’re 10 weeks pregnant so you and your partner have time to consider the option of further tests to find out if your baby will be born with sickle cell disease.
Newborn screening for sickle cell disease
In England screening for sickle cell disease is offered as part of the newborn blood spot test (heel prick test).
This can help to:
- indicate whether your baby has sickle cell disease if pregnancy screening suggested they were at high risk but you decided not to have tests to confirm the diagnosis at the time
- identify any babies with sickle cell disease whose parents were not screened during pregnancy
- show if your baby has the sickle cell trait
- pick up certain other inherited conditions, such as cystic fibrosis
If newborn screening suggests your baby may have sickle cell disease, a second blood test will be carried out to confirm the diagnosis.
Testing for sickle cell carriers
A blood test can be done at any time to find out if you carry sickle cell and are at risk of having a child with sickle cell disease.
This is also known as having the sickle cell trait.
Getting tested can be particularly useful if you have a family history of sickle cell disease or your partner is known to carry the sickle cell trait.
If you think you could be a carrier, ask for a test from your GP surgery.
Both men and women can have the test.
Treatments for sickle cell disease
People with sickle cell disease need treatment throughout their lives. This is usually delivered by different health professionals in a specialist sickle cell centre.
It’s also important for people with sickle cell disease to look after their own health using self care measures, such as by avoiding triggers and managing pain.
A number of treatments for sickle cell disease are available.
For example:
- drinking plenty of fluids and staying warm to prevent painful episodes
- painkillers, such as paracetamol or ibruprofen (sometimes treatment with stronger painkillers in hospital may be necessary)
- daily antibiotics and having regular vaccinations to reduce your chances of getting an infection
- a medicine called hydroxycarbamide (hydroxyurea) to reduce symptoms
- regular blood transfusions if symptoms continue or get worse, or there are signs of damage caused by sickle cell disease
- an emergency blood transfusion if severe anaemia develops
The only cure for sickle cell disease is a stem cell or bone marrow, but they’re not done very often because of the risks involved.