How would you treat ESRD patients on hemodialysis with recurrent AV fistula thrombosis found with low protein C activity?

For ESRD patients with decreased Protein C activity level, the purported etiology may be a dialyzable substance in uremic plasma that interferes with most clotting assays for Protein C activity. This suggests against inherited Protein C deficiency in such a patient who did not previously have suspicious history of thrombosis. Does this finding actually meaningfully increase thrombotic risk, and how should it inform decisions about the use of anticoagulation, especially in the context of planned kidney transplant?