ABO and immunogenetic variation in the pathogenesis of heparin-induced thrombocytopenia (HITT)

Background information

Heparin is administered to 12 million individuals annually, and heparin-induced thrombocytopenia (HITT) occurs in up to 2.4% of heparin-treated patients. HITT is an unpredictable, life-threatening, immune-mediated adverse reaction to heparin treatment. Immune cells help defend the body from invading pathogens, and, at times, they can respond abnormally to the presence of drugs. Their role in HITT is being studied to understand the cellular mechanisms of this condition for better prevention and treatment. The inability to predict HITT remains a critical barrier to the safe use of heparin. 

About the study

This study is spearheaded by Dr. Jason Karnes,  PharmD, PhD, BCPS, University of Arizona and co-investigated by Dr. Elizabeth Phillips. It focuses on identifying intrinsic immune cell involvement in HITT. CDSI, in collaboration with the Division of Hematology and Oncology and the Clinical Coagulation Laboratory at VUMC, is facilitating the recruitment and enrollment of patients into the study.

Members of the Clinical Coagulation Laboratory at VUMC are identifying eligible patients, and CDSI staff are approaching patients’ providers about participation in the study. Patients consenting to participate are asked to provide blood samples and DNA that is isolated from patients’ blood. Additionally, research staff collect information regarding participants’ hospitalizations, heparin doses and durations, platelet counts, surgical histories, and co-morbidities. Each patient diagnosed with HITT is invited for a follow-up study visit at least 90 days after the initial test result.  

We expect this study to identify the biological markers of HITT that will facilitate early diagnosis of the condition. In addition, this study will help identify immune cells associated with HITT and enable the development of accurate models of how immunologic and genetic functions contribute to this adverse drug reaction.   

Questions? 

Please email drugsafetyresearch@vumc.org for more information.