Calciphylaxis is a kidney complication causing calcium buildup inside fat and skin blood vessels. It leads to painful skin lesions and often causes serious infection. Clinical trials are investigating treatments.

Calciphylaxis is also called calcific uremic arteriolopathy.

It’s most often seen in people:

Although a rare condition, if you suspect you have calciphylaxis, do not hesitate to contact your doctor. Early treatment may improve your outlook.

The main symptom of calciphylaxis includes skin lesions on the lower limbs or areas with higher fat content, such as the:

  • breasts
  • buttocks
  • abdomen

The lesions eventually progress to extremely painful ulcers or nodules, which are difficult to heal.

A person with calciphylaxis may have higher levels of calcium (hypercalcemia) and phosphate (hyperphosphatemia) in the blood. They may also have symptoms of hyperparathyroidism.

Other symptoms of calciphylaxis include:

Symptoms like fatigue and weakness, however, may be symptoms of dialysis rather than calciphylaxis.

Calciphylaxis occurs from a buildup of calcium (calcification) inside the blood vessels. The exact cause of this buildup isn’t clear, but multiple processes are likely at play.

One contributing factor may be problems with the metabolism of minerals and hormones, including:

The disruption in mineral metabolism is thought to result from kidney disease, but the exact mechanism isn’t truly understood.

This is especially true since calciphylaxis can occur in people with regular kidney function. More research is needed to better understand the condition.

Calciphylaxis is considered a rare condition, but the rate is increasing.

People with advanced kidney disease are at the highest risk of having calciphylaxis, with it occurring in 0.4 to 4% of people on dialysis.

Although calciphylaxis is more commonly reported in people receiving dialysis, it may also occur in those who:

People with typical kidney function may sometimes receive a calciphylaxis diagnosis if they also have:

A 2024 study of people from New Zealand and Australia found that the median age of 333 people who reported calciphylaxis while on dialysis was 63. Just over half of them were female.

A doctor might suspect calciphylaxis based on the presence of painful skin lesions. If such physical symptoms are present, they’ll perform a physical examination or skin biopsy — both important tools to help confirm calciphylaxis.

Your doctor might also run several tests to rule out other complications of chronic kidney disease. Some diagnostic tests may include:

Currently, an effective treatment or cure for calciphylaxis isn’t yet available. Today’s treatments focus on:

  • caring for the skin lesions
  • preventing infections
  • correcting blood concentrations of calcium and phosphorous

Treating the related wounds and lesions might include:

A health professional may prescribe medications to treat the wounds and to correct atypical calcium and phosphorus concentrations in the blood. These may include:

  • Intravenous sodium thiosulfate: a chelating agent for calcium and iron often used in off-label treatment
  • Cinacalcet (Sensipar): a drug used to treat high levels of calcium in the blood of people with certain parathyroid gland problems or chronic kidney disease
  • Phosphorous binders (noncalcium-containing): can reduce the levels of phosphorus in the blood without altering calcium levels

The Massachusetts General Hospital finished a clinical trial in 2019 to evaluate whether vitamin K supplements can treat calciphylaxis. Results have yet to be posted.

If medication doesn’t control your calcium and phosphorous levels, you may need surgery to remove one or more parathyroid glands (parathyroidectomy). Your doctor may also recommend increasing your dialysis sessions.

Since calciphylaxis is often debilitating, you may need nutritional and psychological support and pain management.

Calciphylaxis is a highly fatal condition. The 1-year survival rate is less than 50%. Death is usually a result of complications, such as infections and sepsis.

Successful management of calciphylaxis symptoms is possible, and early diagnosis and treatment can lead to better outcomes even without a cure. The survival rate is expected to improve as more research is performed.

Discuss with your doctor how to reduce your risk for certain risk factors that may increase your chances of developing calciphylaxis.

Ask your doctor about possible involvement in clinical trials for calciphylaxis treatments.

Calciphylaxis often occurs in people with end stage kidney disease and those who are on dialysis. But it can sometimes occur in people with regularly functioning kidneys. Early diagnosis may improve the outcome.

Calcium buildup typically causes it, but other underlying factors might contribute. Common symptoms include painful skin lesions or ulcers.

More research on treatment for calciphylaxis can help improve the survival rates. Talk with your doctor about how to become involved.