Sequential Bone Scintigraphy and the Evolution of Warfarin-Mediated Calcific Uremic Arteriolopathy

Calcific uremic arteriolopathy (CUA), also known as calciphylaxis, is a complex syndrome of deranged mineral metabolism and vascular calcification leading to tissue ischemia that primarily occurs in end-stage renal disease (ESRD) patients on maintenance hemodialysis (HD). We report a case illustrating a temporal relationship between long-term warfarin anticoagulation and development of CUA in a patient with pre-dialysis chronic kidney disease (CKD) who progressed to ESRD. Serial ^99mTc-methylene diphosphonate bone scintigraphy documented the evolution of metastatic CUA over a 5-month period following HD initiation. Given the temporality demonstrated here via imaging, we speculate that warfarin's influence on vitamin K-dependent matrix Gla protein function coupled with risk factors associated with ESRD led to the development of metastatic CUA.