title: Vitamin K antagonists predispose to calciphylaxis in patients with end-stage renal disease.
abstract: OBJECTIVE
  Calciphylaxis is associated with a poor prognosis in dialysis patients, and its pathogenesis remains incompletely understood. Although the use of vitamin K antagonists (VKA) has been implicated, previous reports are conflicting. We aimed to determine if vitamin K antagonists conferred an increased risk of calciphylaxis in patients on dialysis.
  
  
  METHODS
  We performed a single-centre, retrospective cohort study of 2,234 patients receiving dialysis, and compared the characteristics of those with and without calciphylaxis.
  
  
  RESULTS
  We identified 5 cases of calciphylaxis (all female) between January 2009 and December 2013. Overall, 142 patients (6.4%) were treated with VKA during the study period. Calciphylaxis was more common in the VKA group (4 of 142 patients, OR = 61, 95% CI 6.7-546, p = 0.0001). VKA was withdrawn in all cases and treatment instituted with sodium thiosulphate, cinacalcet and supportive measures. All patients recovered, although there was one sudden cerebrovascular death during follow-up.
  
  
  CONCLUSIONS
  Treatment with VKA predisposes to the development of calciphylaxis.
authors.affiliation: School of Clinical Medicine, University of Cambridge, Cambridge, UK.
authors.forename: Peter A G
authors.initials: PA
authors.lastname: Galloway
authors.forename: Ragada
authors.initials: R
authors.lastname: El-Damanawi
authors.forename: Victoria
authors.initials: V
authors.lastname: Bardsley
authors.forename: Nicholas R
authors.initials: NR
authors.lastname: Pritchard
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Fry
authors.forename: Sanjay K
authors.initials: SK
authors.lastname: Ojha
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Hiemstra
mesh_terms: D000328:Adult; D000368:Aged; D000672:Amputation Stumps / Q000473:pathology; D000925:Anticoagulants / Q000009:adverse effects* / Q000627:therapeutic use; D001160:Arterioles / Q000473:pathology; D002115:Calciphylaxis / Q000139:chemically induced* / Q000453:epidemiology / Q000473:pathology; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D017582:Renal Replacement Therapy; D012189:Retrospective Studies; D020246:Venous Thrombosis / Q000150:complications / Q000188:drug therapy; D014812:Vitamin K / Q000037:antagonists & inhibitors*
chemical_list: D000925:Anticoagulants; D014812:Vitamin K