Study of Blood Platelets in Sickle Cell Disease
Study of Blood Platelets in Sickle Cell Disease
We are studying if sickle cell disease blood platelets are larger than normal and how they
 may cause obstruction of blood vessels. We are also trying to study the reasons why large
 platelets are found in patients with sickle cell disease.
Research volunteers are seen in the Outpatient Research Center by the Principal Investigator
 or another physician. A detailed history is obtained, a physical examination is performed,
 and blood (usually 4 tablespoons) is obtained for additional tests. The research volunteer's
 previous medical records will be requested. Upto 5 additional blood samples may be obtained
 in a subgroup of patients.
Inclusion Criteria:

 -  Adults and children > 7 years of age with sickle cell disease (Hb SS) who are not
 taking hydroxyurea and are not receiving routine blood transfusion therapy.

 Exclusion Criteria:

 -  Current hydroxyurea therapy or,

 -  Hydroxyurea use within the past 3 months

 -  Blood transfusion or exchange transfusion within the past 3 months

 -  Current treatment with aspirin or clopidogrel