What You Should Know About Abnormal Blood Clotting - Pathology

Deadly Pathology/Killer Blood Clots
Roger S. Riley, M.D., Ph.D.
8
Table IV
Laboratory Assays for Thrombotic Disorders*
Abnormality Coagulation Laboratory Assays Molecular Assays
Antiphospholipid antibody Screen - Activated partial thromboplastin None
syndrome
time (aPPT)($25). Confirmation - dilute
Russell Viper Venom assay (dRVVT)($100)
Factor V Leiden APC resistance ($250) Factor V Mutation Assay ($325)
Prothrombin G20210A
mutation
None
Prothrombin G20210A mutation
($325)
Homocysteine abnormalities Plasma homocysteine levels ($175) MTHFR mutation ($325)
Antithrombin III deficiency Antithrombin III function and levels ($200) None
Protein C deficiency Protein C function and levels ($425) None
Protein S deficiency Protein S function and levels ($375) None
Increased factor VIII Factor VIII activity ($175) None
Increased plasminogen Plasminogen activity and levels ($415) None
Plasminogen Activator PAI-1 inhibitor assay ($230)
None
Inhibitor-1
* The most common abnormalities are listed first. The approximate cost is only a guide; laboratory costs may
vary considerably.
Most deficient individuals presenting with thrombosis are managed acutely with heparin therapy, followed by long
term oral anticoagulant therapy. Commercially prepared concentrates are available for use post-surgically and
during parturition in AT III deficient individuals. Protein C concentrates are available on a compassionate use
basis.
Summary
Thromboembolic diseases are presently the leading cause of death, and responsible for more than 1,000,000
deaths/year in the United States alone. Fortunately, thromboembolic disease is preventable, and many recent
scientific discoveries have lead to the ability to estimate a person’s disease risk, so that appropriate preventive
therapy can be instituted. Most doctors agree that persons who have a strong family history of thromboembolic
disease or who develop thrombosis at an early age (i.e.,