Medication Contraindications

Warfarin

Although there have been no clinical studies, it seems prudent to avoid the use of warfarin in patients with ENPP1 Deficiency or ABCC6 Deficiency.  Matrix Gla protein (MGP), a potent anti-mineralization factor, needs to be activated by a vitamin K-dependent enzyme, and warfarin interferes with the vitamin K cycle.  Warfarin has also been shown to accelerate ectopic mineralization in mice.  

Crysvita / Burosumab 

This medication is typically used to treat X-Linked Hyophosphatemic Rickets (XLH).  Patients with ENPP1 Deficiency should avoid the use of burosumab as it can worsen or actually induce calcification.  There is anecdotal evidence of patients in our community, who were originally misdiagnosed with XLH, suffering from increased vascular calcification as a result of being treated with burosumab.