Heparin-Induced Thrombocytopenia | Validating 4Ts for Heparin Induced Thrombocytopenia (HIT)

Heparin-Induced Thrombocytopenia research study

What is the primary objective of this study?

The purpose of this study is to evaluate a scoring tool to help determine the presence of Heparin Induced Thrombocytopenia (HIT), which is an adverse reaction to heparin. We hypothesize that this scoring tool will be very useful in excluding patients who are suspected of having HIT.

Who is eligible to participate?

Inclusion Criteria: - Patients with suspected HIT. Exclusion Criteria:

Which medical condition, disease, disorder, syndrome, illness, or injury is researched?

Heparin-Induced Thrombocytopenia

Study Interventions

Interventions can include giving participants drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available or noninvasive approaches such as surveys, education, and interviews.

Other:Scoring 4Ts and Chong scaleTwo physicians will independently score both the 4Ts and the Chong scale on all patients enrolled in this study.

Other:Blood drawPatient serum will be collected to perform Serotonin Release Assay testing to verify the presence of HIT.

Study Arms

Research studies and clinical trials typically have two or more research arms. An arm is a group of people who receive the same treatment in the study.

Suspected HITThose who are clinically suspected of having HIT will be enrolled in this study.

Study Status

Unknown status

Start Date: August 2009

Completed Date:


Type: Observational


Primary Outcome: To validate the 4Ts as a pretest probability tool for HIT.

Secondary Outcome: To determine the inter-rater variability for scoring the 4Ts.

Study sponsors, principal investigator, and references

Principal Investigator: Chee M Chan, MD

Lead Sponsor: Washington Hospital Center

Collaborator: GlaxoSmithKline

More information:

Lo GK, Juhl D, Warkentin TE, Sigouin CS, Eichler P, Greinacher A. Evaluation of pretest clinical score (4 T's) for the diagnosis of heparin-induced thrombocytopenia in two clinical settings. J Thromb Haemost. 2006 Apr;4(4):759-65.

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