Calciphylaxis is a disease in which blood vessels (veins and arteries) become blocked by a build-up of calcium in the walls of the vessels, preventing blood from flowing to the skin or internal organs.  The lack of blood flow (ischemia) damages healthy tissue and causes it to die (necrosis).  The most obvious and frequent symptom of calciphylaxis is damage to the skin, as ulcers can develop and become infected easily.  Calciphylaxis can also affect fat tissue, internal organs, and skeletal muscle, causing infections, pain, and organ failure.  These symptoms are often irreversible, and many individuals with calciphylaxis may not survive more than a few months after they are diagnosed due to infection that spreads throughout the body (sepsis), or organ failure.  The exact cause of calciphylaxis is unknown.  Treatments may include medications to reduce pain, antibiotics to treat infections, and various approaches to preventing the development or worsening of this condition.