How Can Your Laboratory Minimize Over-diagnosis of HIT?

Expires February 1, 2019


Length: 32 minutes


Heparin-induced thrombocytopenia (HIT) is a potentially life-threatening complication of heparin therapy characterized by thrombocytopenia and sometimes thromboembolism following exposure to heparin. The diagnosis of HIT is complex, especially if a patient has other potential causes of thrombocytopenia or thrombosis. A HIT diagnosis requires compatible clinical findings and supportive laboratory evidence. Pre-test prediction algorithms (e.g., the 4T scoring system) have been developed to assist in the clinical evaluation for this condition. Unfortunately, there are many pitfalls associated with laboratory testing for HIT, and these limitations are important to understand in order to make an accurate HIT diagnosis.


Upon completion of this activity, participants should be able to:

  • Define clinical features characteristic of HIT and understand implications of diagnosis.
  • Use pre-test scoring systems to estimate probability of HIT.
  • State the pros and cons associated with the various laboratory tests for HIT.
  • Apply this knowledge toward effective lab medicine consultation to help improve diagnostic accuracy of HIT.

Intended Audience

This program is appropriate for clinicians, pathologists, medical technologists, nurses, pharmacists, and other allied health staff.

Level of Instruction



Photo of Jill Adamski, M.D., Ph.D.Jill Adamski, M.D., Ph.D.
Associate Professor of Laboratory Medicine and Pathology
Mayo Clinic College of Medicine and Science
Consultant in Laboratory Medicine
Department of Laboratory Medicine and Pathology
Mayo Clinic
Phoenix, Arizona



The following types of credit are offered for our Virtual Lecture programs:


To obtain credit:

  1. Watch the video.
  2. Complete the posttest and evaluation that launches immediately following the video.
  3. Generate and print your certificate.

For an instruction sheet that describes the process, see

Note: Participants requesting P.A.C.E.® credit, in compliance with ASCLS P.A.C.E.® program requirements, must attain a score of 70% or higher on the posttest to obtain a certificate.

Mayo Medical Laboratories is approved as a provider of continuing education programs in the Clinical Laboratory Sciences by the ASCLS P.A.C.E.® program. This program has been approved for a maximum of .5 P.A.C.E® contact hour. Level of instruction for this program is intermediate.

Note: This program does not qualify for State of Florida or State of California credit because it does not meet the minimum credit requirement of 50 minutes in length.


MML Education

This post was developed by our Education and Technical Publications Team.