Calciphylaxis in patients on hemodialysis: a prevalence study.

BACKGROUND: Calciphylaxis is characterized by painful, violaceous, mottled skin lesions (livedo reticularis) that may progress to tissue necrosis, nonhealing ulcers, gangrene, and potentially amputation, sepsis, or death. The prevalence and characteristics of patients who have calciphylaxis need further identification to predict which patients on dialysis may benefit from close monitoring or early surgical intervention.
METHODS: All 242 patients undergoing hemodialysis in an outpatient unit were reviewed retrospectively during a 15-month cross-sectional study of the prevalence and characteristics of calciphylaxis.
RESULTS: Ten patients (prevalence, 4.1%) had calciphylaxis. Patients with calciphylaxis were significantly younger (49 versus 60 years; p = 0.01), had undergone hemodialysis longer (80 versus 20 months; p < 0.0001), and had higher median serum calcium (9.7 versus 9.2 mg/dl; p = 0.03), phosphate (8.2 versus 5.7 mg/dl; p = 0.001), calcium phosphate product (81.5 versus 52.9; p = 0.0004), parathyroid hormone (1496 versus 138 pg/ml; p < 0.0001), and alkaline phosphatase levels (188 versus 89 IU/L; p = 0.0001). Bone surveys were positive in all 10 patients with calciphylaxis compared with 49 (21%) of the 232 patients without calciphylaxis (p < 0.0001). All patients who underwent parathyroidectomy for calciphylaxis had dramatic healing of the ulcers.
CONCLUSIONS: The presence of calciphylaxis is higher among younger patients who had undergone longer periods of hemodialysis. Therefore this group of patients should be monitored aggressively and treated expeditiously for complications of secondary hyperparathyroidism.