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 (abdominal) pain 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
• eyesight problems, such as floaters, 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

Find out how sickle cell disease is treated

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

The Sickle Cell Society has more information about the inheritance of sickle cell disease, including what the risks are if a parent has sickle cell disease themselves.

Who's most at risk of sickle cell disease

In the UK, sickle cell disease is most commonly seen in people of African and Caribbean backgrounds.

A simple blood test will show whether you're a carrier. This is done routinely during pregnancy and after birth, but you can ask to have the test at any time.

Read more about getting tested for the sickle cell trait and being a sickle cell carrier.

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.

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.

Find out more about screening for sickle cell disease during pregnancy

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.

Find out more about the newborn blood spot test

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 or nearest sickle cell and thalassaemia centre.

Both men and women can have the test.

Find out more about sickle cell carriers

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

Get more advice about living with sickle cell disease

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.

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

Contact your GP if these measures do not work or the pain is particularly severe. If this is not possible, go to your local A&E.

You may need treatment with very strong painkillers, such as morphine, in hospital for a few days.

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 – read more about treatments for priapism
• 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.

A helpful leaflet about sickle cell disease

The NHS Sickle Cell and Thalassaemia Screening Programme has a helpful parents' guide to managing sickle cell disease (PDF, 3.57Mb).

There are a number of things you can do, and precautions you can take, to stay as healthy as possible if you have sickle cell disease.

Managing sickle cell pain

You can reduce your risk of painful episodes (sickle cell crises) by avoiding things that can trigger them.

Try to:

• drink plenty of fluids, particularly during hot weather – dehydration increases the risk of a sickle cell crisis
• avoid extreme temperatures – you should dress appropriately for the weather and avoid sudden temperature changes, such as swimming in cold water
• be careful at high altitudes – the lack of oxygen at high altitudes may trigger a crisis (travelling by plane should not be a problem because planes are pressurised to maintain a steady oxygen level)
• avoid very strenuous exercise – people with sickle cell disease should be active, but intense activities that cause you to become seriously out of breath are best avoided
• avoid alcohol and smoking – alcohol can cause you to become dehydrated and smoking can trigger a serious lung condition called acute chest syndrome
• relax – stress can trigger a sickle cell crisis, so it may help to learn relaxation techniques, such as breathing exercises

Your healthcare team can give you more advice about avoiding triggers.

It's also a good idea to be prepared for treating painful episodes at home. Keep a ready supply of painkillers (paracetamol or ibuprofen) and consider buying some heated pads to soothe the pain.

Find out more about treatments for sickle cell disease

Avoiding infections

You'll usually be given antibiotics and advised to have vaccinations to help prevent most serious infections, but there are also things you can do to reduce your risk.

For example, you should make sure you follow good food hygiene measures to prevent food poisoning.

• wash your hands with soap and water regularly – particularly after going to the toilet and before handling food
• cook food thoroughly – particularly make sure reheated food, meat and most types of seafood are steaming hot in the middle before eating them
• store food correctly – make sure chilled food is kept in the fridge and cooked leftovers that you intend to reheat later are not left out for long

Make sure you speak to your GP or healthcare team if you're planning to travel aboard, as this may mean you need extra medication or vaccinations.

For example, if you're travelling to an area where malaria is found, it's important to take antimalarial medication.

You may also need to take extra food and water precautions abroad.

Pregnancy and contraception

Women with sickle cell disease can have a healthy pregnancy, but it's a good idea to speak to your healthcare team for advice first.

It may be useful to find out if your partner is a carrier of sickle cell and discuss the implications of this with a counsellor.

Some sickle cell disease medicines, such as hydroxycarbamide, can harm an unborn baby. You may need to be stop taking them before trying to get pregnant.

There's an increased risk of problems, such as anaemia, sickle cell pain, miscarriage and pre-eclampsia, during pregnancy.

And you may need extra monitoring and treatment during pregnancy to help prevent problems.

If you're not planning a pregnancy, use a reliable form of contraception.

Surgery precautions if you have sickle cell disease

It's important to let your healthcare team know if you need to have an operation under general anaesthetic at any point. Tell your surgeon that you have sickle cell disease.

This is because general anaesthetic can cause problems for people with sickle cell disease, including an increased risk of experiencing a sickle cell crisis.

You may need close monitoring during surgery to make sure you're getting enough fluids and oxygen and are kept warm.

Sometimes you may be need a blood transfusion beforehand to reduce the risk of complications.

When to get medical advice

Make sure you know when to get medical advice and where to go, as sickle cell disease can cause a number of serious problems that can appear suddenly.

Problems to look out for include:

• a high temperature over 38C (or any increased temperature in a child)
• severe pain that's not responding to treatment at home
• severe vomiting or diarrhoea
• a severe headache, dizziness or a stiff neck
• breathing difficulties
• very pale skin or lips
• sudden swelling in the tummy
• a painful erection (priapism) lasting more than 2 hours
• confusion, drowsiness or slurred speech
• fits (seizures)
• weakness on 1 or both sides of the body
• changes in vision or sudden vision loss

Contact your GP or healthcare team straight away if you develop any of these symptoms.

If this is not possible, go to your nearest A&E. If you're not well enough to travel to hospital yourself, dial 999 for an ambulance.

Make sure that the medical staff looking after you know you have sickle cell disease.

If you're a carrier of sickle cell, it means you carry one of the genes that causes sickle cell disease, but you do not have the condition yourself.

It's also known as having the sickle cell trait.

People who carry sickle cell will not develop sickle cell disease, but may be at risk of having a child with sickle cell disease and may occasionally need to take precautions to stop them becoming unwell.

You can find out if you're a carrier of sickle cell by having a simple blood test.

The NHS Sickle Cell and Thalassaemia Screening Programme has a detailed leaflet about being a sickle cell carrier (PDF, 773kb).

Who can be a sickle cell carrier?

Anyone can be a carrier of sickle cell, but it's much more common in people from certain ethnic backgrounds.

In the UK, most people who carry the sickle cell trait have an African or Caribbean family background.

Testing for sickle cell carriers

Screening for sickle cell disease is offered to all pregnant women in England, although most women will be at low risk and will not need to have a blood test to check if they're a carrier.

Find out more about screening for sickle cell disease in pregnancy

Anyone can ask to have a free blood test to find out if they're a carrier at any point.

This can be useful if:

• you want to find out if you're at risk of having a child with sickle cell disease
• you have a family history of sickle cell disease or carrying the sickle cell trait
• your partner carries the sickle cell trait

You can request the test from your GP surgery or nearest genetic counsellor, who'll discuss the result and implications with you if you're found to carry sickle cell.

Having children

If you carry the sickle cell trait, you're at risk of having children with sickle cell disease, although this can only happen if your partner is also a carrier or has sickle cell disease themselves.

If you're planning to have a child and you know you're a carrier, it's a good idea for your partner to be tested.

If you and your partner both carry sickle cell, there's a:

• 1 in 4 chance each child you have will not have sickle cell disease or be a carrier
• 1 in 2 chance each child you have will be a carrier, but will not have sickle cell disease
• 1 in 4 chance each child you have will be born with sickle cell disease

If both of you are carriers and you're planning to have a baby, talk to your GP about getting a referral to a genetic counsellor, who can explain the risks to your children and what your options are.

These include:

• having tests during pregnancy to see if your baby will have sickle cell disease
• adopting a child
• trying IVF with a donor egg or sperm
• trying pre-implantation genetic diagnosis (PGD)

PGD is similar to IVF, but the resulting embryos are tested to check that they do not have sickle cell disease before they're implanted in the womb.

The Human Fertilisation and Embryology Authority (HFEA) has more information about PGD.

Rare health risks

You're not at risk of developing sickle cell disease if you carry the sickle cell trait.

The only time you may be at risk of health problems is in rare cases where you might not get enough oxygen, such as:

• having surgery under general anaesthetic – make sure medical staff are aware you carry the sickle cell trait before your operation
• during regular intensive physical activity – make sure you drink plenty of fluids during training and avoid extreme exhaustion

There's also a very small risk of developing kidney problems associated with carrying sickle cell.

Apart from these uncommon situations, you can lead a completely normal and healthy life if you're a sickle cell carrier.

People who carry other blood disorders

People who are carriers of the sickle cell trait are also at risk of having a child with a blood disorder if their partner is a carrier of a different type of blood disorder.

You can find more detailed information about some of the other types of carrier in these leaflets:

• Beta thalassaemia carrier (PDF, 804kb)
• Delta beta thalassaemia carrier (PDF, 779kb)
• Haemoglobin O Arab carrier (PDF, 831kb)
• Haemoglobin C carrier (PDF, 396kb)
• Haemoglobin D carrier (PDF, 947kb)
• Haemoglobin E carrier (PDF, 505kb)
• Haemoglobin Lepore carrier (PDF, 756kb)