title: Warfarin related nephropathy: a case report and review of the literature.
abstract: BACKGROUND
  Warfarin related nephropathy is one of the potential complications of warfarin therapy. Despite the well described histological entity, the clinical course and approach to warfarin related nephropathy in patients requiring life-long anticoagulation is however not well described in the literature.
  
  
  METHODS
  We report the clinical course of a 56 years old Chinese lady who presented with over anti-coagulation and acute kidney injury while on warfarin therapy for permanent atrial fibrillation and mechanical valve replacement. Renal biopsy was performed as the acute kidney injury was persistent despite normalization of the International Normalized Ratio and the diagnosis of warfarin related nephropathy was made. Temporary interruption of anti-coagulation, in combination with oral N-acetylcysteine resulted in subsequent stabilization of renal function.
  
  
  CONCLUSIONS
  The diagnosis of warfarin induced nephropathy should be considered in patients presenting with unexplained acute kidney injury and over anti-coagulation. Awareness of this clinical entity is important for clinician managing anti-coagulation therapy and renal function should be monitored regularly in patients who are on warfarin therapy.
authors.affiliation: Department of Renal Medicine, Singapore General Hospital, 20 College Road, Academia, Level 3, Singapore, 169856, Singapore.
authors.forename: Chee Yong
authors.initials: CY
authors.lastname: Ng
authors.affiliation: Department of Renal Medicine, Singapore General Hospital, 20 College Road, Academia, Level 3, Singapore, 169856, Singapore. tan.chieh.suai@sgh.com.sg.
authors.forename: Chieh Suai
authors.initials: CS
authors.lastname: Tan
authors.affiliation: National Heart Centre Singapore, Singapore, Singapore.
authors.forename: Chee Tang
authors.initials: CT
authors.lastname: Chin
authors.affiliation: National Heart Centre Singapore, Singapore, Singapore.
authors.forename: See Lim
authors.initials: SL
authors.lastname: Lim
authors.affiliation: National Heart Centre Singapore, Singapore, Singapore.
authors.forename: Ling
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Department of Renal Medicine, Singapore General Hospital, 20 College Road, Academia, Level 3, Singapore, 169856, Singapore.
authors.forename: Keng Thye
authors.initials: KT
authors.lastname: Woo
authors.affiliation: Department of Pathology, Singapore General Hospital, Singapore, Singapore.
authors.forename: Puay Hoon
authors.initials: PH
authors.lastname: Tan
mesh_terms: D000111:Acetylcysteine / Q000627:therapeutic use; D058186:Acute Kidney Injury / Q000209:etiology* / Q000473:pathology / Q000628:therapy; D000925:Anticoagulants / Q000009:adverse effects*; D001281:Atrial Fibrillation / Q000188:drug therapy; D005260:Female; D016166:Free Radical Scavengers / Q000627:therapeutic use; D006350:Heart Valve Prosthesis; D006801:Humans; D008875:Middle Aged; D014859:Warfarin / Q000009:adverse effects*; D028761:Withholding Treatment
chemical_list: D000925:Anticoagulants; D016166:Free Radical Scavengers; D014859:Warfarin; D000111:Acetylcysteine
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