Clinical Trial: Validating 4Ts for Heparin Induced Thrombocytopenia (HIT)

Study Status: Recruiting
Recruit Status: Unknown status
Study Type: Observational

Official Title: Prospectively Validating the 4Ts and Chong Score for Heparin Induced Thrombocytopenia

Brief Summary: 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.

Detailed Summary:

HIT is an immune response to heparin that can result in thrombogenic thrombocytopenia. It is often a difficult diagnosis to make, and its diagnosis is dependent upon both clinical and serologic criteria. Due to this ambiguity, increased testing and treatment may occur until serologic test results return. Recently, scoring tools have been developed to assist with the diagnosis of this disease. However, these scoring tools have yet to be validated. Thus, we plan to conduct a prospective, observational study to validate two scoring tools, the 4Ts and the Chong scale, in the diagnosis of HIT.

In order to validate these scoring tools, two physicians will independently score the 4Ts and the Chong scale for all patients suspected of having HIT. These patients will be identified if a physician has ordered HIT antibody testing using the enzyme immunoassay (EIA) method. Confirmatory testing with a serotonin release assay (SRA) will also be performed.


Sponsor: Washington Hospital Center

Current Primary Outcome:

  • To validate the 4Ts as a pretest probability tool for HIT. [ Time Frame: End of study. ]
  • To validate the Chong scale as a tool to determine the post-test probability for HIT. [ Time Frame: End of study. ]


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • To determine the inter-rater variability for scoring the 4Ts. [ Time Frame: End of study. ]
  • To determine the inter-rater variability for scoring the Chong scale. [ Time Frame: End of study. ]


Original Secondary Outcome: Same as current

Information By: Washington Hospital Center

Dates:
Date Received: July 24, 2009
Date Started: August 2009
Date Completion:
Last Updated: July 24, 2009
Last Verified: July 2009