Extrait

Background and study aims This study aims to understand why certain patients bleed excessively. We look at the following groups of patients: 1. Patients with mild bleeding who have been seen by a blood specialist who feels their symptoms could be due to a problem in the platelets (clinically diagnosed platelet defects) 2. Patients who have unexpectedly heavy periods with no obvious cause 3. Patients with lifelong low platelet counts in the blood with no known cause For these populations we suspect that there may be a problem in small cells in the blood, known as platelets, but we are not certain that this is the case. This study is using new and more specialist tests in an attempt to confirm that there is a problem in platelets in these groups and to use this information to help identify the gene or genes that cause this problem. Who can participate? Patients aged under 85 with a platelet disorder of unknown cause What does the study involve? Participants are asked questions about their medical history and complete a bleeding questionnaire. Participants are also asked to give a sample of blood (between 10–50 ml). The blood sample is usually be taken at a local Haematology Clinic, ideally early in the day so that the analyses can be carried out on the same day. Depending on the results of the tests, participants may be asked to give blood on up to three further occasions. This is to carry out different types of tests on the platelets and therefore find out more information on the problem. This can be taken either during a ‘regular’ visit to the Haematology Clinic/surgery or through a specific appointment. There is a minimum of one month between the dates that the blood is taken and no upper time limit on the gap between the donations. The blood samples are sent to research laboratories in Birmingham and/or Sheffield for analysis of the platelets. A frozen sample is also kept for a maximum of 10 years, which may be used to look for gene defects that could cause the platelet problem or changes in blood proteins that may increase your chance of bleeding. The sample is destroyed at this time, or earlier if requested. The sample may be kept for this length of time in the event that we are unable to find a problem with your genes in the first set of investigations. It is possible that, as we gain more knowledge, the sample is investigated at later times to find a gene defect that may be the cause of the bleeding problem. What are the possible benefits and risks of participating? The study will generate important information on possible defects in the platelets and may also identify the genes that are responsible for the defects. The identification of a defect in your platelets may influence clinical treatment. If a gene defect is found, it will be possible to investigate whether one or more members of the participant’s family have the same gene defect, should they wish. Where is the study run from? University of Birmingham (UK) When is the study starting and how long is it expected to run for? December 2010 to December 2016 Who is funding the study? 1. British Heart Foundation (UK) 2. Wellcome Trust (UK) Who is the main contact? Prof. Stephen Watson [email protected]

Critère d'inclusion

• Non-malignant haematology

Liens

• isrctn
• ictrp