Protein C and
protein S are regulatory factors that decrease the risk for clotting.
Deficiencies of protein C or protein S can increase the risk for
clotting. A more common cause of the hypercoagulable state is factor V
Leiden mutation. Protein C and protein S exert their effects via factor
V. When the factor V Leiden mutation is present, this process does not
occur. The case patient has low levels of protein C and protein S.
However, one of the keys in obtaining laboratory measurements is
understanding factors that invalidate the tests. Levels of protein C
and protein S decrease in patients receiving warfarin; therefore, the
low levels that are obtained are meaningless. The only tests of
significance are the genetic tests, because the DNA is unchanged by
warfarin. Prothrombin 20210 is another mutation that can lead to
hypercoagulability, but it is not detected in this case.
- There is no evidence of a hypercoagulable state.
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Seminars in Medical Practice
Hospital Physician Board Review Manuals
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Updated 1/04/08 kkj