title: Resistance to oral vitamin K for reversal of overanticoagulation during Crohn's disease relapse.
abstract: OBJECTIVE
  The purpose of this case report is to describe oral vitamin K resistance in a patient with concomitant Crohn's disease (CD) relapse and supratherapeutic anticoagulation. Additionally, a literature review was conducted to explore the mechanism and supporting evidence for poor response to oral vitamin K during CD relapse.
  
  
  METHODS
  A 36 year-old female presented with an elevated International Normalized Ratio (INR) of 7.8 during a relapse of CD including symptoms of severe, persistent diarrhea and reduced appetite. For excessive anticoagulation, initial management consisted of withholding warfarin for seven days, administering vitamin K in a total dose of 10 mg orally and 1 mg intravenously. One week later, the INR remained elevated at 8.09. Subcutaneous vitamin K, in a dose of 5 mg, was administered on day eight, and the INR was reduced to a subtherapeutic result of 1.2 on day eleven.
  
  
  CONCLUSIONS
  The case report illustrates a poor response to recommended and repeated doses of oral vitamin K and a single, small dose of intravenous vitamin K during CD relapse. However, the patient responded favorably to vitamin K by the subcutaneous route. Current literature and consensus guidelines recommend the oral route of vitamin K as first-line management of overanticoagulation due to warfarin. Present data supports that patients with inflammatory bowel disease including CD have a greater incidence of vitamin K deficiency and malabsorption, and this is likely due to multiple pathological mechanisms.
  
  
  CONCLUSIONS
  Based on this case report, treatment of overanticoagulation in patients with CD relapse should include aggressive management, close monitoring, and consideration of an alternative, parenteral route of vitamin K administration rather than by the oral route due to potential for poor absorption.
authors.affiliation: The University of Oklahoma Health Sciences Center, Department of Pharmacy, Clinical and Administrative Sciences, Oklahoma City, OK 73190-5040, USA. Susan-Fugate@ouhsc.edu
authors.forename: Susan Elaine
authors.initials: SE
authors.lastname: Fugate
authors.forename: April Michelle
authors.initials: AM
authors.lastname: Ramsey
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects*; D003424:Crohn Disease / Q000188:drug therapy*; D062787:Drug Overdose; D004351:Drug Resistance; D005260:Female; D006801:Humans; D019934:International Normalized Ratio; D017211:Treatment Failure; D014812:Vitamin K / Q000008:administration & dosage*; D014859:Warfarin / Q000008:administration & dosage / Q000009:adverse effects*
chemical_list: D000925:Anticoagulants; D014812:Vitamin K; D014859:Warfarin