Phenprocoumon based anticoagulation is an underestimated factor in the pathogenesis of calciphylaxis.

Background: Calciphylaxis is a life threatening complication in renal patients. Of great importance is the identification of concomitant factors for calciphylaxis. Due to the variability of clinical presentation the evaluation of such factors may be obscured when calciphylaxis diagnosis is based just on clinical features. We aimed to characterize associated factors only in patients with calciphylaxis proven by histomorphological parameters in addition to clinical presentation.

Methods: In a single center retrospective study we analyzed 15 patients in an 8 year period from 2008 to 2016. Only patients with clinical features and histomorphological proof of calciphylaxis were included. Criteria for histological diagnosis of calciphylaxis were intimal hyperplasia, micro thrombi or von Kossa stain positive media calcification.

Results: The mean age of patients was 64.8 years. Nine patients (60%) were female; 12 (80%) were obese with a Body-Mass-Index (BMI) > 30 kg/m; 3 (20%) had no renal disease; 12 (80%) had CKD 4 or 5 and 10 (66.7%) had end-stage renal disease (ESRD). One-year mortality in the entire cohort was 73.3%. With respect to medication history, the majority of patients (n = 13 (86.7%)) received vitamin K antagonists (VKA); 10 (66.7%) were treated with vitamin D; 6 (40%) had oral calcium supplementation; 5 (33.3%) had been treated with corticosteroids; 12 (80%) were on proton pump inhibitors (PPI); 13 (86.7%) patients had a clinical proven hyperparathyroidism. Ten (66.7%) patients presented with hypoalbuminemia at diagnosis.

Conclusions: The evaluation of biopsy proven calciphylaxis demonstrates that especially treatment with vitamin K antagonists and liver dysfunction are most important concomitant factors in development of calciphylaxis. As progression and development of calciphylaxis are chronic rather than acute processes, early use of DOACs instead of VKA might be beneficial and reduce the incidence of calciphylaxis.