Calciphylaxis (kal-sih-fuh-LAK-sis) is a rare, serious disease. It involves a buildup of calcium in small blood vessels of fat tissues and skin.

Calciphylaxis symptoms include blood clots, lumps under the skin and painful open sores called ulcers. If an ulcer becomes infected, it can be life-threatening.

The exact cause of calciphylaxis isn't clear. But people with the disease usually have kidney failure. That's a condition in which the kidneys no longer work as they should. Often, these same people also have received kidney failure treatments such as dialysis or a kidney transplant. Calciphylaxis can happen in people without kidney disease too.

Calciphylaxis treatments include various medicines, procedures and surgery. Treatment can help prevent blood clots and infections, reduce calcium buildups, heal sores, and ease pain.


Calciphylaxis symptoms include:

  • Large netlike patterns on the skin that may look purple-pink in color.
  • Deep, painful lumps in the skin that can become ulcers. The ulcers often have a black-brown crust that doesn't heal on its own. Ulcers tend to appear in areas with high fat content, such as the stomach, thighs, buttocks and breasts. But they can form anywhere.
  • Infections from ulcers that don't heal.


The exact cause of calciphylaxis isn't known. The disease involves the buildup of calcium in the smallest parts of the arteries in fat tissues and skin.

Many people who get calciphylaxis also have kidney failure or receive dialysis. It's not known why people with kidney failure or people receiving dialysis are at higher risk of calciphylaxis.

For some people, the calcium buildup in calciphylaxis is linked with small organs in the neck called parathyroid glands. If the glands release too many parathyroid hormones, that can cause calcium to collect. But the link isn't clear. Most people with seriously overactive parathyroid glands don't get calciphylaxis. And many people with kidney failure and calciphylaxis don't have overactive parathyroid glands.

Other factors that seem to play roles in calciphylaxis include:

  • A greater tendency for blood to clot. Blood clots can deprive fat tissues and skin of oxygen and nourishment.
  • Reduced blood flow in small arteries, which can lead to skin lumps and ulcers.
  • Thickening or scarring of tissue, also called fibrosis.
  • Ongoing damage to the thin layer of cells that lines blood vessels. This also is called vascular endothelial injury.
  • Swelling, called inflammation, in the body.

Risk factors

Calciphylaxis most often affects people who have kidney failure. Other risk factors include:

  • Being born female.
  • Obesity.
  • Diabetes mellitus.
  • Liver failure, when the liver stops working as it should.
  • A history of dialysis. This procedure removes waste and extra fluid from the blood when the kidneys no longer can.
  • A greater tendency for blood to clot, also called a hypercoagulable state.
  • An imbalance in the body of the minerals calcium or phosphate, or of the protein albumin.
  • Some medicines, such as warfarin (Jantoven), calcium-binding agents and corticosteroids.


Complications of calciphylaxis include:

  • Serious pain.
  • Large, deep ulcers that do not heal on their own.
  • Blood infections.
  • Death, mainly due to infection or organ failure.

Often, the outlook for people with calciphylaxis isn't hopeful. Finding and treating any infections early is key to preventing serious complications.


There isn't a clear way to prevent calciphylaxis. But if you are on dialysis or have low kidney function due to advanced chronic kidney disease, it's important to keep blood levels of calcium and phosphorus under control.

Keeping blood levels of phosphorus under control often is a challenge. Your healthcare professional might have you take medicines with meals. You also may need to restrict certain foods that are high in phosphorus. It's very important to follow your healthcare professional's directions and go to all follow-up healthcare checkups.

If you have calciphylaxis, your healthcare team helps you prevent ulcer infections or other complications. You may need to apply special wound dressings or clean the ulcers daily to prevent germs called bacteria from growing.


Diagnosis involves finding out if calciphylaxis is the cause of your symptoms. Your healthcare professional reviews your health history, asks about your symptoms and gives you a physical exam.

You also may need tests such as:

  • Skin biopsy. During this procedure, your healthcare professional removes a small tissue sample from an area of affected skin. Then, a lab checks the sample.
  • Blood tests. A lab can measure various substances in your blood. These include creatinine, calcium, phosphorus, parathyroid hormone and vitamin D. The results help your healthcare team check how well your kidneys are working.
  • Imaging tests. These can be useful if biopsy results aren't clear or if a biopsy can't be done. X-rays may show calcium buildups in the blood vessels. These buildups are common in calciphylaxis and in other advanced kidney diseases.


Often, more than one treatment is needed for calciphylaxis. Treatments can restore oxygen and blood flow to the skin and reduce calcium buildup.

Restoring oxygen and blood flow to the skin

Medicine that helps keep blood from clotting can restore blood flow to affected tissues. These blood-thinning medicines are called anticoagulants. If these don't help, an experimental treatment may be available that can dissolve blood clots in the tiny blood vessels of the skin. This treatment is a type of medicine called a low-dose tissue plasminogen activator.

Another backup treatment option involves breathing pure oxygen in a pressurized chamber. This is called hyperbaric oxygen therapy. It's not available everywhere. A small amount of research suggests that this therapy may help control infections and limit tissue loss while the main treatments take effect.

Wound care is a crucial part of calciphylaxis treatment. So it can be very helpful to have a team of wound care specialists.

Reducing calcium buildup

Reducing calcium buildup in arteries may be helped by:

  • Dialysis. If you get kidney dialysis treatment, your healthcare professional may change the medicines used and how long and often you get dialysis. It might be helpful to increase the number and length of dialysis sessions.
  • Changing medicines. Your healthcare professional reviews your current medicines and gets rid of possible triggers for calciphylaxis. These triggers include warfarin, corticosteroids and iron. If you take calcium or vitamin D supplements, your healthcare professional may change the amount you take or have you stop taking them.
  • Taking medicines. A medicine called sodium thiosulfate can lower calcium buildup in the small arteries. It's given through a needle in a vein three times a week, usually during dialysis. Your healthcare professional may recommend that you take a medicine called cinacalcet (Sensipar), which can help control parathyroid hormone (PTH). Other medicines may be used to improve the balance of calcium and phosphorus in your body.
  • Surgery. If an overactive parathyroid gland that makes too much PTH plays a role in your condition, surgery may be a treatment option. Surgery called a parathyroidectomy can remove all or part of the parathyroid glands.

Applying intensive wound treatment

For sores to heal, some of the tissue damaged by calciphylaxis may need to be removed with surgery. This is called debridement. Sometimes, tissue can be removed using other methods, such as wet dressings. Medicines called antibiotics can clear up infections caused by germs. Antibiotics can help treat and prevent ulcer infections.

Pain control

You'll likely be offered medicines to manage pain due to calciphylaxis or during wound care. A pain medicine specialist may need to be involved if you're prescribed opioid pain medicines.

Preparing for an appointment

You may start by seeing your healthcare professional. Or you may be referred to a skin doctor called a dermatologist or a kidney doctor called a nephrologist.

Some other healthcare professionals who may become part of your healthcare team include:

  • An internal medicine doctor, called an internist.
  • A surgeon.
  • A wound care specialist.
  • A pain management expert.

Here's some information to help you get ready for your appointment.

What you can do

When you make the appointment, ask if there's anything you need to do in advance. For example, you may be told not to eat for a certain number of hours before some tests. This is called fasting. It's also a good idea to bring a family member or friend with you. A person you trust can help you remember all of the information from your appointment.

It's also helpful to make a list of:

  • Your symptoms, including any that do not seem related to the reason for your appointment.
  • Key personal information, including major stresses, recent life changes and family medical history.
  • All medicines, vitamins or other supplements you take, including the amounts you take.
  • Questions to ask your healthcare team.

For calciphylaxis, some basic questions to ask your healthcare team include:

  • What's likely causing my symptoms? Are there other possible causes?
  • What tests do I need?
  • What treatment do you recommend?
  • I have other health conditions. How can I best manage these conditions together?
  • Do I need to change my diet?
  • What's the outlook for my health?
  • Are there brochures or other printed material I can have? What websites do you recommend?

What to expect from your doctor

Your healthcare professional is likely to ask you questions such as:

  • When did your symptoms begin?
  • Have your symptoms been ongoing or do they come and go?
  • How bad are your symptoms?
  • Does anything seem to make your symptoms better?
  • What, if anything, appears to make your symptoms worse?

Content From Mayo Clinic Updated: 07/08/2024
© 1998-2024 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. Terms of Use