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Hemostasis in Sickle Cell Disease--Infancy to Adulthood

This study has been completed.
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI) Identifier:
First received: May 25, 2000
Last updated: May 12, 2016
Last verified: March 2005
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).

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:


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.


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.


Ages Eligible for Study:   up to 100 Years   (Child, Adult, Senior)
Genders Eligible for Study:   Male
Accepts Healthy Volunteers:   No
No eligibility criteria
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Please refer to this study by its identifier: NCT00005703

Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
OverallOfficial: Marie Stuart Thomas Jefferson University
  More Information Identifier: NCT00005703     History of Changes
Other Study ID Numbers: 4310  R01HL055185 
Study First Received: May 25, 2000
Last Updated: May 12, 2016
Health Authority: United States: Federal Government

Additional relevant MeSH terms:
Hematologic Diseases
Anemia, Sickle Cell
Anemia, Hemolytic, Congenital
Anemia, Hemolytic
Genetic Diseases, Inborn processed this record on October 27, 2016