We are intrigued by Dr Kovacs' finding that in more than 95% of patients with thrombosis, protein C, protein S, and antithrombin levels are normal in the acute setting. If this finding is corroborated across institutions and laboratories, it would be reasonable to follow his recommendations for those patients requiring indefinite anticoagulation. However, if anticoagulation is planned for a finite period only, we would still favor testing the patient after the anticoagulant course is completed.
Federman DG, Kirsner RS. Timing of Hypercoagulable Screens—Reply. Arch Intern Med. 2002;162(5):613-614. doi: