Vascular Calcification and Calciphylaxis in Peritoneal Dialysis Patients

Cardiovascular disease is the leading cause of death in end-stage renal disease (ESRD) patients, including hemodialysis and peritoneal dialysis (PD). Nearly half of the PD patient population dies from cardiovascular disease and many more have debilitating consequences associated with it, including stroke, limb amputation and chronic pain. Vascular calcification, a phenomenon closely related to the development of cardiovascular disease is prevalent in patients with chronic kidney disease (CKD). Vascular calcification is not a single disease, but rather a manifestation of multiple complex pathologic pathways, it is commonly divided into 2 different types based on the histologic location of the calcium deposits within the arteries walls: Intimal vascular calcification, and medial vascular calcification. Intimal calcium deposition is associated with atherosclerosis, the leading cause of coronary artery disease in patients with and without CKD. Medial calcium deposition disproportionately affects patients with CKD and results in arterial stiffness and ventricular dysfunction. A third form of ectopic calcification: Calciphylaxis, will also be reviewed here. In Calciphylaxis there is medial calcium deposition and microthrombi formation in the lumen of arterioles of the dermis and subcutaneous tissues, which leads to ischemia of these affected tissues and produces a devastating clinical disease. Recent insights into the molecular pathways associated with ectopic calcification and the knowledge gained from various forms of arterial calcification associated with genetic variations will likely in the near future, lead to the identification of patients at higher risk for vascular calcification and to the development of more effective treatments and prevention strategies.