Calciphylaxis: A Mimic of Vasculitis

Calciphylaxis, which literally means 'protection through calcification', is a fatal disease characterised by ischemic necrosis of cutaneous tissue resulting from vascular intimal fibroplasia, thrombi, and calcifications in the arterioles. The pathophysiology involves the accumulation of calcium in the skin, vascular space, and adipose tissue due to abnormal serum levels of calcium, phosphorus, and parathyroid hormone (PTH), particularly in patients with end-stage renal disease (ESRD). The clinical presentation typically involves severe ischemic and neuropathic pain, which may occur independently of skin lesions. There are no specific diagnostic criteria or laboratory tests; the disease is primarily recognised based on clinical findings. There is no definitive information on treatment due to the incomplete understanding of its mechanism; therefore, the prevention of calciphylaxis is of paramount importance. Upon examination of cases in the literature, a mortality rate of 34% is observed despite appropriate treatment and care. Given its rarity, calciphylaxis is prone to being overlooked. Through this review presenting two cases seen in our rheumatology clinic, our aim is to raise awareness about calciphylaxis which can mimic vasculitis, and promote early diagnosis.