Unbalanced protein S deficiency due to warfarin treatment as a possible cause for thrombosis.
The prothrombin time/International Normalized Ratio is an accurate parameter for following most warfarin-treated patients. However, it reflects mostly factor VII levels, and significant disproportionate alterations in other vitamin K-dependent factors may not be reflected properly. We report a rare case of a woman who developed arterial thrombosis whilst receiving therapeutic doses of warfarin, and was found to have a significant and unbalanced protein S deficiency. Discontinuation of warfarin resulted in complete normalization of coagulation factors, and no further thrombotic events under treatment with enoxaparin, with a follow-up of 2.5 years.
Haran
Michal Z
MZ
Haematology Institute, Kaplan Medical Centre, Rehovot, Israel. michal.haran@gmail.com
Lichman
Inna
I
Berebbi
Alain
A
Weinmann
Eran
E
Rosenberg
Nurit
N
D000925:Anticoagulants / Q000009:adverse effects* / Q000627:therapeutic use; D017984:Enoxaparin / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019934:International Normalized Ratio; D008875:Middle Aged; D018455:Protein S Deficiency / Q000097:blood*; D013927:Thrombosis / Q000097:blood / Q000209:etiology* / Q000517:prevention & control; D014859:Warfarin / Q000009:adverse effects* / Q000627:therapeutic use
D000925:Anticoagulants; D017984:Enoxaparin; D014859:Warfarin