Calciphylaxis

Calciphylaxis

Calciphylaxis [calcific uremic arteriolopathy (CUA)] is usually associated with secondary and tertiary hyperparathyroidism. However, calciphylaxis can also be seen in the absence of chronic renal failure and has been reported in patients with primary hyperparathyroidism due to a parathyroid adenoma or carcinoma. Calciphylaxis occurs when the levels of calcium and phosphate in the blood exceed their solubility level, leading to calcium-phosphate deposits in arteries that compromise the vasculature. These ischemic changes result in plaque-like lesions that progress to painful nodules, calcification of small vessels, tissue ischemia, pain, infarction and secondary infection, sepsis, and death. Calciphylaxis has 60–80% mortality rate.

Calciphylaxis is diagnosed on the basis of physical examination, laboratory, and histopathologic findings. When medical therapy has failed in the setting of secondary/tertiary hyperparathyroidism with calciphylaxis, parathyroidectomy is the preferred treatment. In primary hyperparathyroidism, early recognition and aggressive wound care with debridement are important in managing this condition. However, resection of the offending parathyroid gland should be strongly considered.

When calciphylaxis is present, early detection is critical to the successful management of this condition. Although medical therapy can be effective, surgical resection of the diseased parathyroid glands can be curative and potentially life saving. A multidisciplinary approach involving early diagnosis, aggressive medical management, operative debridement, and parathyroidectomy has the best chance of improving survival in calciphylaxis.

Traditional care:

- Minimizing calcium intake,
- Calcimimetics,
- Cautious vitamin D analogs,
- Strict phosphate control,
- Surgical emergent parathyroidectomy.

Recent Therapeutic Options:

- Intravenous Sodium Thiosulfate Therapy
- Treatment with a Bisphosphonate
- Hyperbaric Oxygen Therapy
- Steroids

CLINICAL PRACTICE GUIDELINES KDOQI: PARATHYROIDECTOMY IN PATIENTS WITH CHRONIC KIDNEY DISEASE (Clinical Practice Guidelines for Bone Metabolism and Disease in Chronic Kidney Disease):

Indication for surgical parathyroidectomy is the presence of calciphylaxis with PTH levels that are elevated (>500 pg/mL [55.0 pmol/L]), as there are several reports of clinical improvement in patients with calciphylaxis after such therapy. It is important to emphasize, however, that not all patients with calciphylaxis have high levels of PTH, and parathyroidectomy—in the absence of documented hyperparathyroidism—should not be undertaken.

References

1) KDOQI Clinical Practice Guidelines for Bone Metabolism and Disease in Chronic Kidney Disease (http://www.kidney.org/professionals/KDOQI/guidelines_bone/Guide14.htm)

2) Ross EA. Evolution of treatment strategies for calciphylaxis. Am J Nephrol. 2011;34(5):460-7.

3) Goel SK, Bellovich K, McCullough PA. Treatment of severe metastatic calcification and calciphylaxis in dialysis patients. Int J Nephrol. 2011 Feb 24;2011:701603.