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.
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.
Symptoms of sickle cell disease
People born with sickle cell disease tend to have problems from early childhood, although some children have few symptoms and lead normal lives most of the time.
The main symptoms of sickle cell disease are:
- painful episodes called sickle cell crises, which can be very severe and last for days or weeks
- an increased risk of serious infections
- anaemia (where red blood cells cannot carry enough oxygen around the body), which can cause tiredness and shortness of breath
- Other problems include delayed growth, strokes and lung problems
Causes of sickle cell disease
- 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 is inherited
- Genes come in pairs. You inherit 1 set from your mother and 1 set from your father.
- To be born with sickle cell disease, a child has to inherit a copy of the sickle cell gene from both their parents.
- This usually happens when both parents are “carriers” of the sickle cell gene, also known as having the sickle cell trait.
- Or it can happen when 1 parent has sickle cell disease and the other is a carrier of it.
- Sickle cell carriers do not have sickle cell disease themselves, but there’s a chance they could have a child with sickle cell disease if their partner is also a carrier.
- If both parents are sickle cell carriers, there’s a:
- 1 in 4 chance each child they have will not inherit any sickle cell genes and will not have sickle cell disease or be able to pass it on
- 1 in 2 chance each child they have will just inherit a copy of the sickle cell gene from 1 parent and be a carrier
- 1 in 4 chance each child they have will inherit copies of the sickle cell gene from both parents and will be born with sickle cell disease
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 can cause symptoms of sickle cell disease because they do not live as long as normal red blood cells and can become stuck in blood vessels.
Treatment
Sickle cell disease usually requires lifelong treatment.
Children and adults with sickle cell disease are supported by a team of different healthcare professionals working together at a specialist sickle cell centre.
Your healthcare team will help you learn more about sickle cell disease, and work with you to come up with an individual care plan that takes into account all your needs and health concerns.
Preventing painful episodes
The main thing you can do to reduce your chances of experiencing a painful episode (sickle cell crisis) is to try avoiding possible triggers.
You may be advised to:
- drink plenty of fluids to avoid dehydration
- wear warm clothing to stop you getting cold
- avoid sudden temperature changes, such as swimming in cold water
Medicine for sickle cell pain
If you continue to have episodes of pain, a medicine called hydroxycarbamide (hydroxyurea) may be recommended. You usually take it as a capsule once a day.
Hydroxycarbamide can lower the amount of other blood cells, such as white blood cells and platelets (clotting cells), so you’ll usually have regular blood tests to monitor your health.
If you have regular episodes of pain, you may also be able to have a medicine called crizanlizumab. Crizanlizumab can be taken on its own or alongside hydroxycarbamide. You will usually be given crizanlizumab by injection into a vein every 4 weeks.
Self-help for treating a sickle cell crisis
If you have a sickle cell crisis, you can usually manage it at home.
The following things can help:
- take over-the-counter painkillers, such as paracetamol or ibuprofen (do not give aspirin to children under 16 unless a doctor has prescribed it) – if the pain is more severe, your GP may prescribe stronger painkillers
- have plenty to drink
- use a warm towel or a wrapped heated pad to gently massage the affected body part – many pharmacies sell heat pads that you can use for this purpose
- distractions to take your mind off the pain – for example, children might like to read a story, watch a film or play their favourite computer game
Preventing infections if you have sickle cell disease
People with sickle cell disease are more vulnerable to infections.
Most people need to take a daily dose of antibiotics, usually penicillin, often for the rest of their life.
Long-term use of antibiotics will not pose any serious risks to your health.
Children with sickle cell disease should also have all the routine vaccinations, and possibly also additional vaccinations like the annual flu vaccine and the hepatitis B vaccine.
Treatments for sickle cell-related anaemia
Anaemia often causes few symptoms and may not require specific treatment.
But dietary supplements like folic acid, which helps stimulate the production of red blood cells, may sometimes be required to help improve anaemia if your child has a restricted diet, such as a vegetarian or vegan diet.
Anaemia caused by sickle cell disease is not the same as the more common iron deficiency anaemia.
Do not take iron supplements to treat it without seeking medical advice, as they could be dangerous.
If anaemia is particularly severe or persistent, treatment with blood transfusions or hydroxycarbamide may be necessary.
Stem cell or bone marrow transplants
Stem cell or bone marrow transplants are the only cure for sickle cell disease, but they’re not done very often because of the significant risks involved.
Stem cells are special cells produced by bone marrow, a spongy tissue found in the centre of some bones. They can turn into different types of blood cells.
For a stem cell transplant, stem cells from a healthy donor are given through a drip into a vein.
These cells then start to produce healthy red blood cells to replace the sickle cells.
A stem cell transplant is an intensive treatment that carries a number of risks.
The main risk is graft versus host disease, a life-threatening problem where the transplanted cells start to attack the other cells in your body.
Stem cell transplants are generally only considered in children with sickle cell disease who have severe symptoms that have not responded to other treatments, when the long-term benefits of a transplant are thought to outweigh the possible risks.
Treating other problems
Sickle cell disease can also cause a number of other problems that may need to be treated.
For example:
- a short course of hormonal medicine may be prescribed to trigger puberty in children with delayed puberty
- gallstones may be treated with gallbladder removal surgery
- bone and joint pain can be treated with painkillers, although more severe cases may require surgery
- persistent and painful erections (priapism) may require medication to stimulate blood flow or using a needle to drain blood from the penis
- leg ulcers can be treated by cleaning the ulcer and dressing it with a bandage
- people at increased risk of having a stroke, or those who have had a stroke, may need regular blood transfusions or treatment with hydroxycarbamide
- acute chest syndrome, a serious lung condition, usually requires emergency treatment with antibiotics, blood transfusions, oxygen and fluids given into a vein – hydroxycarbamide may be needed to prevent further episodes
People who need a lot of blood transfusions may also need to take medicine called chelation therapy. This reduces the amount of iron in their blood to safe levels.