Anticoagulation in a Patient With Mechanical Prosthetic Valves and Calcific Uremic Arteriolopathy on Warfarin

Calciphylaxis, or calcific uremic arteriolopathy (CUA), is a rare vascular calcific disease that is most often associated with renal dysfunction and warfarin, particularly end-stage renal disease (ESRD). This condition causes debilitatingly painful skin lesions, oftentimes plaques, throughout areas of cutaneous and subcutaneous adiposity. The progression of these lesions to black eschar with ulceration is the hallmark of CUA. In this report, we present the case of a Caucasian female with a past medical history of nephrogenic systemic fibrosis (NSF), ESRD, and mechanical aortic and mitral valves, anticoagulated with warfarin, who developed CUA. In the setting of mechanical prosthetic valves, vitamin K antagonists (VKA) and aspirin are the only evidence-based antithrombotic therapies. This case presents challenging decision-making when managing anticoagulant therapy in the absence of applicable guidelines.