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Hemostasis in Sickle Cell Disease--Infancy to Adulthood

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT00005703
First Posted: May 26, 2000
Last Update Posted: May 13, 2016
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)
  Purpose
To assess in older children and adults with sickle cell disease (SCD) whether intrinsic activation (relevant to the origin of pain and acute inflammation) occurs only during vasocclusive crisis (VOC).

Condition
Anemia, Sickle Cell Blood Disease

Study Type: Observational

Resource links provided by NLM:


Further study details as provided by National Heart, Lung, and Blood Institute (NHLBI):

Study Start Date: July 1995
Study Completion Date: July 1998
Detailed Description:

BACKGROUND:

Investigations into hemostatic abnormalities associated with sickle cell disease have been numerous. The data suggested that thrombin generation and fibrin formation were increased during steady state, with conflicting data whether further activation occurred in vaso-occlusive crisis. Platelet activation during VOC occurred, with variable findings during steady state. A selective, concomitant evaluation of the hemostatic pathways i.e. intrinsic, tissue factor (TF) or extrinsic activation, fibrinolysis, and platelet-endothelial activation had not been reported. Neither had a longitudinal evaluation been performed in infants during the unique transition period when HbF levels fall from 70 to 80 percent to less than 10 percent.

The study was part of an initiative on "Coagulation, Platelets and Thrombosis in Sickle Disease Pathophysiology". The Request for Applications was released in October 1994.

DESIGN NARRATIVE:

The studies used appropriate 'negative' and 'positive' control groups. Studies included intrinsic markers [kininogen profiling, high molecular weight kininogen (HK) and low molecular weight kininogen (LK) cleavages, western blotting of HK and LK, and kallikrein-alpha2 macroglobulin; extrinsic markers [TF and factor V11a]; other activation and fibrinolytic markers [prothrombin F1.2, FPA, TAT, tPA, PAI-I, D-dimer and plasma alpha2 antiplasmin]; platelet- endothelial markers [evaluation of activation dependent epitopes]. Unequivocal demonstration of contact pathway activation during VOC provided a crucial link between VOC and its accompanying phenomenon including pain, and inflammation. Finally, the studies provided a unique perspective on the continuum of hemostatic changes that unfolded during the course of SCD, and those that developed as vascular insufficiencies supervened in the adult.

The study completion date listed in this record was obtained from the "End Date" entered in the Protocol Registration and Results System (PRS) record.

  Eligibility

Information from the National Library of Medicine

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Ages Eligible for Study:   up to 100 Years   (Child, Adult, Senior)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No
Criteria
No eligibility criteria
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00005703


Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
Investigators
OverallOfficial: Marie Stuart Thomas Jefferson University
  More Information

ClinicalTrials.gov Identifier: NCT00005703     History of Changes
Other Study ID Numbers: 4310
R01HL055185 ( U.S. NIH Grant/Contract )
First Submitted: May 25, 2000
First Posted: May 26, 2000
Last Update Posted: May 13, 2016
Last Verified: March 2005

Additional relevant MeSH terms:
Anemia, Sickle Cell
Hematologic Diseases
Anemia, Hemolytic, Congenital
Anemia, Hemolytic
Anemia
Hemoglobinopathies
Genetic Diseases, Inborn