Calciphylaxis can occur in kidney transplant recipients who have functioning grafts, investigators reported in Clinical Kidney Journal
According to David Cucchiari, MD, and colleagues from the Hospital Clinic of Barcelona in Spain, “calciphylaxis cannot be considered only the consequence of long-standing uraemia, and the term [calcific uremic arteriolopathy] may lead to disagreement and misclassification.
“It should be interpreted as the clinical syndrome caused by critical ischaemia of calcified terminal skin (candelabra) arterioles, independently of whether the cause of chronic vascular calcification has been uraemia, chronic inflammation, ageing, pharmacological, genetic predisposition or all of them in combination.”
The team examined 14 cases of calciphylaxis after kidney transplantation diagnosed at their institution from 1990 to 2020 and 31 cases from the medical literature, published 1969 to 2019. Calciphylaxis developed during the first year after kidney transplantation in 43.2% of patients. Median creatinine at diagnosis was 2.4 mg/dL. Distal purpura or ulcers occurred in a third of patients. Parathyroid levels were above 500 pg/mL and below 100 pg/mL in 50.0% and 25.0% of cases, respectively. Of the cohort, 55.6% died.
Clinical presentation, immunosuppression, and management varied over the 50 years. After the year 2000, 23.8% patients had diabetes mellitus, 23.8% had a previous parathyroidectomy, and 42.9% were treated with vitamin K inhibitors. Recent calciphylaxis treatments included sodium thiosulphate (42.6%), bisphosphonates (36.8%), and calcimimetics (31.6%).
Dr Cucchiari’s team proposed that calciphylaxis development after kidney transplantation reflects the presence of traditional Framingham risk factors (older age, hypertension, diabetes, dyslipidemia, smoking, and obesity) and non-traditional risk factors, including graft dysfunction, longer kidney disease vintage, abnormal mineral metabolism, immunosuppression, and vitamin K antagonists. Vascular calcification prior to transplant surgery could predispose patients to later calciphylaxis, along with trauma, hypotension, and a hypercoagulable state, they explained.
“Given the high mortality and the rarity of the disease, it would be desirable in the future to share patients’ data in international registries and to refine management by studying the pathogenesis more thoroughly and introducing new drugs,” the investigators noted.
Guillén-Olmos E, Torregrosa JV, Garcia-Herrera A, Ganau S, Diekmann F, Cucchiari D. Development of calciphylaxis in kidney transplant recipients with a functioning graft. Clin Kidney J. Published online October 26, 2021. doi:10.1093/ckj/sfab205