Sickle cell disease web chat on Thursday 16 February
Join us on Thursday 16 February for a web chat about sickle cell disease with Dr Kirstin Lund, consultant in paediatric haematology at our Trust. Dr Lund is the clinical lead for paediatric haemoglobinopathies in our children’s haematology, blood and marrow transplantation service.
Dr Lund will answer your questions on sickle cell disease in children and young adults.
Everyone, including patients, the public, GPs and other health workers is invited to submit questions. All questions can be submitted anonymously.
You can submit your questions here from 12.30 on Thursday 16 February, then Dr Lund will join us at 13.00 to get started. You're also welcome to email questions to firstname.lastname@example.org or tweet your questions to @ImperialNHS.
You can also follow the chat through Twitter by following our Twitter handle @ImperialNHS.
Archive of chat
Hi everyone! Kirstin has now arrived, so let's get started!
Comment from guest: What is sickle cell disease?
Dr Kirstin Lund: Sickle cell disease is a form of anaemia and is one of the most common inherited genetic disorders. The genetic mutation arises in haemoglobin, the molecule which is responsible for carrying oxygen in red blood cells. The mutation causes sickling of blood cells when the blood is deoxygenated. This results in the formation of crescent-shaped cells, which can become stuck in the blood vessels. The damage to these cells causes their early destruction, leading to anaemia.
Comment from guest: what are the signs and symptoms?
Dr Kirstin Lund: One of the commonest complications of sickle cell disease is vaso-occlusive crisis, which often manifests as bone pain - this occurs when the sickle cells cause blockade of the blood vessels. Sickling can also occur within the lung, which can result in a serious complication called 'chest crisis', or in the brain, where it can cause a stroke.
Chronic sickling or pooling of blood within the spleen results in damage to this organ, which reduces the body's ability to fight infection - this is a particularly serious problem in young patients.
Comment from guest: Do both the mother and father have to be carriers of sickle cell disease for a child to develop it?
Dr Kirstin Lund: Yes, sickle cell disease is an autosomal recessive condition, which means the genetic mutation must be passed on by both parents for the disease to occur. People with a mutation inherited from only one parent are known as sickle carriers. They generally have minimal or no symptoms themselves but have the capacity to pass on sickle cell disease to their children if their partner also carries the sickle cell trait.
Comment from guest: At what age do symptoms first begin to appear?
Dr Kirstin Lund: Symptoms of sickle cell disease are not evident at birth. Babies produce a different oxygen carrying molecule called haemoglobin F (HbF) which reduces the degree of red cell sickling. During the first six months of life the level of HbF reduces and at this point symptoms may start to appear.
Comment from guest: Why is sickle cell disease more prevalent in some ethnic groups more than others?
Dr Kirstin Lund: Sickle cell disease has a prevalence of 1-2% in West and Central Africa and is also common in parts of the Middle East and India. The selective benefit of carrying the sickle cell mutation in these populations is that it confers protection against malaria.
In the UK the mutation is rare but migration has meant that the disorder has become more common (especially in London). It is estimated that there are between 12,000 and 15,000 affected individuals in the UK (approx 300 new births per year).
Comment from guest: How is sickle cell normally treated?
Dr Kirstin Lund: The initial options for managing sickle cell disease involve using blood transfusions or a medicine called hydroxycarbamide (also known as hydroxyurea). These treatments help manage the symptoms of anaemia but are not a cure.
Currently bone marrow transplant is the only curative form of treatment for sickle cell disease. In the future it is hoped that gene therapy will become an alternative curative option.
Comment From anon: How does a bone marrow transplant work to cure sickle cell disease?
Dr Kirstin Lund: Bone marrow transplantation is a complex process. The first step involves using chemotherapy to weaken or destroy the patient's bone marrow - this includes the blood stem cells which make the abnormal sickle cells and also the patient's own infection-fighting immune system. This is necessary to prevent the patient rejecting the new bone marrow from the donor.
The second step involves giving new healthy blood-forming stem cells from the donor. These are 'transplanted' and over time they differentiate to form a new population of red and white blood cells in the host.
Currently the NHS only funds bone marrow transplant up to the age of 19 years. This is because the potential complications associated with transplant increase significantly in older patients and therefore the risks of undertaking the procedure may out-weigh the benefits.
Comment from Trinity Brooke: 1. How does the disease affect the person (physically and psychologically) in every day life?
2. Can they lead a normal-ish life with the disease?
Dr Kirstin Lund: Sickle cell disease affects individual patients in many different ways. Some patients are relatively asymptomatic and others really struggle to cope with this illness both physically and psychologically.
Many patients are able to live with chronic anaemia without it interfering too much with day to day activities. In the clinic we closely monitor for symptoms of anaemia such as fatigue and breathlessness. If this becomes an increasing problem the options of treatment with blood transfusion or hydroxycarbamide are discussed.
It is important for the medical team to address the psychological element of living with a chronic disease. Patients are often understandably anxious about what will happen to them in the future, particularly if they have personal experiences of relatives with the condition.
That's all we've got time for today, thank you very much to Kirstin! We have had some really interesting questions and we're sorry for not having the chance to answer them all during the chat. If you email your question to email@example.com, Kirstin will aim to answer them directly in due course. Thanks everyone for joining us!