MACS Study – Microparticles and Coagulation in Sickle Cell Disease: An Observational Study to Measure the Levels of Circulating Microvesicles and Coagulation Activation Parameters in Patients With Sickle Cell Disease in the in- and Out-patient Setting.

Study point of contact

Sara Trompeter, MB ChB BSC MRCPCH FRCPath
[email protected]


3 United Kingdom sites

Study type






About the study

Sickle cell disease (SCD) is an inherited disorder of the red blood cell. It is now the
commonest genetic disorder in the UK and of childhood stroke, with up to 40% of children
having a stroke (clinical or picked up on a scan) by school age. Patients are prone to
develop acute crises necessitating hospital admission and resulting in long-term
complications. Such events result in considerable morbidity, disability and mortality with
its consequent burden on patients, families, the health service and society as a whole.
Doctors have very little ability to predict who will get ill and when and so it is very
difficult to known when and how to administer treatments. Furthermore there is very little in
the way of treatments available and the mainstay of prevention is a chronic blood transfusion
programme which is expensive, requires time off work and school and can be fraught with
complications. This, in a population who is frequently educationally and socially
disadvantaged at the outset. Recent evidence in sickle cell disease and other diseases that
have similar underlying processes, points towards the importance of microparticles
(circulating broken pieces of cells) and the coagulation system as being important. By
comparing levels of these particles and molecules in patients with those found in healthy
volunteers and with other measures known to be important, this study hopes to identify their
role so as to improve the management of these patients and potentially to lead the way for
new therapies. Participants will be required to donate a small amount of blood (1 teaspoon in
the very young, two in older children and adults). The investigators aim to take this sample
where possible when people are having a blood test in any case.

participation requirements

– Subject Inclusion Criteria:

Patient (or parent if child) able to give informed consent Compound heterozygote or
homozygote for a sickling disorder (i.e. has sickle cell disease) Having a blood test in
any case

– Healthy volunteer Inclusion Criteria:

Person (or parent if child) able to give informed consent If a child, having a blood test
or cannula inserted in any case Ethnically matched – of African origin Must know their
sickle cell status or have it tested as part of the study and agree to have this result
given to them and their G.P.

participation restrictions

– Subject Exclusion Criteria:

Inability to meet all


  • London, United Kingdom, Whittington Hospital NHS Trust, N19 5NF
  • London, United Kingdom, University College London Hospitals NHS Foundation Trust, NW1 2PJ
  • London, United Kingdom, Guy's and St Thomas' NHS Foundation Trust, SE1 7EH