Helping children affected by disability and infections

This research was completed on 25 July 2012

Published on 24 May 2011

Around one baby in every 2,000 born in the UK has sickle cell disease.¹ They face a lifetime of ill health and a shortened life expectancy. Researchers are developing a new diagnostic test, which could be cheaper, easier and quicker than existing tests. For the first time ever, it could also identify babies who are most at risk of severe illness, so they can benefit from immediate and intensive treatment.

What's the problem and who does it affect?

A lifetime of ill health and hospital visits

Over 12,000 people in the UK have sickle cell disease – the UK’s most common severe genetic disorder. An estimated 20 million people are affected worldwide.^1-3 Symptoms usually start early – in babies who are just six to nine months old.

Children with sickle cell disease face a lifetime of ill health. They have attacks of intense pain – called crises – which can last several days. They are prone to infections and anaemia, which can be life-threatening. They are at risk of a variety of complications, including leg ulcers, strokes and organ failure, and they have a shortened life expectancy.

Currently, the most reliable diagnostic tests for sickle cell disease are complicated, requiring skilled technicians and sophisticated, expensive equipment. The tests are time consuming and are often not useful in an emergency situation.

What’s more, none of the existing tests can predict how severe a baby’s illness is likely to be. Babies who are at risk of the most severe symptoms, who might benefit greatly from early and intensive treatment, cannot be easily identified before they become poorly.

What is the project trying to achieve?

Perfecting a new diagnostic test

The researchers are developing a simple new diagnostic test for sickle cell disease.

Babies with the disease have abnormal red blood cells. The test works by detecting these cells. It involves mixing a blood sample with a special sugar solution in low oxygen. Red blood cells from a baby who has sickle cell disease burst in the liquid, which becomes pink. Cells from a healthy baby do not burst, and the liquid stays clear.

The aim of this project is to perfect the diagnostic test, so it can be used routinely at the bedside.

The researchers have four key questions:

1. What is the best sort of sugar solution to use for bursting blood cells?
2. What is the easiest way to create low oxygen levels in the sugar solution?
3. What is the easiest and simplest way to detect burst red blood cells?
4. Can the test predict how severe a child’s illness is likely to be – does the extent or speed of bursting correlate with the severity of children’s symptoms?

What are the researchers' credentials?

The project team includes Dr John Gibson, from the University of Cambridge, Professor Clive Ellory, from the University of Oxford, and Dr David Rees of King’s College Hospital, London. All three researchers have a keen interest in sickle cell disease and have published extensively in leading research journals.

Dr Gibson and Professor Ellory are both scientists who are at the forefront of research into red blood cells in the UK and recognised experts internationally. Researchers in their well-equipped laboratories have worked together for over 30 years on how abnormalities in red blood cells cause disease.

The third member of the group, Dr Rees, is a consultant at King’s College Hospital with a particular interest in improving the lives of children with sickle cell disease. Around 120 children and adults with sickle cell disease who attend clinics at Kings are donating blood samples for use in this research.

Together, the three research groups have unparalleled expertise and knowledge, giving them the opportunity to make practical advances in understanding sickle cell disease.

Who stands to benefit from this research and how?

Improving children's lives

The researchers aim to improve diagnosis of sickle cell disease. Babies and children stand to benefit most, as symptoms usually start in the first year of life.

The researchers are developing a new blood test for sickle cell disease, which they believe could have important advantages over existing tests:

• The new test could be simpler, cheaper and easy to distribute. It would not require expensive laboratory equipment or highly skilled personnel. More children in developing countries might therefore have access to testing - in some parts of Africa the disease is particularly common, with up to one in 60 babies being affected.²
• The new test could give faster results, making it suitable for use in emergencies. If children need emergency surgery, for example, it is important to know whether they have sickle cell disease.
• The new test could allow the first ever prediction of how severe a baby’s illness is likely to be. Babies who are most at risk could then benefit from earlier, more intensive treatment, which could alleviate suffering, prevent complications like strokes, and greatly improve quality of life.

References

1. NHS Choices. Sickle cell anaemia. http://www.nhs.uk/conditions/sickle-cell-anaemia/Pages/Introduction.aspx Website accessed 11 January 2011.
2. Howard J, Davies SC. Sickle cell disease in North Europe. Scand J Clin Lab Invest 2007; 67:27-38.
3. Aliyu ZY, Kato GJ, Taylor J, Babadoko A, Mamman AI, Gordeuk VR, Gladwin MT. Sickle cell disease and pulmonary hypertension in Africa: A global perspective and review of epidemiology, pathophysiology, and management. Am J Hematol 2008; 83:63-70.