Hemostasis in Sickle Cell Disease--Infancy to Adulthood

This study has been completed.
Sponsor:
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)
ClinicalTrials.gov Identifier:
NCT00005703
First received: May 25, 2000
Last updated: June 23, 2005
Last verified: March 2005
  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
Study Design: Observational Model: Natural History
Time Perspective: Longitudinal

Resource links provided by NLM:


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

Study Start Date: July 1995
Estimated 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.

  Eligibility

Genders Eligible for Study:   Male
Accepts Healthy Volunteers:   No
Criteria

No eligibility criteria

  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00005703

Sponsors and Collaborators
Investigators
Investigator: Marie Stuart Thomas Jefferson University
  More Information

No publications provided

ClinicalTrials.gov Identifier: NCT00005703     History of Changes
Other Study ID Numbers: 4310
Study First Received: May 25, 2000
Last Updated: June 23, 2005
Health Authority: United States: Federal Government

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

ClinicalTrials.gov processed this record on October 01, 2014