ABSTRACT Cefazolin Induced Factor V inhibition Wan
Deraman Wan Noormastura1, Aung Kyi Lai Lai1 Acquired factor V inhibition is a rare but challenging medical problem which associated with autoimmune diseases, malignancy and exposure to bovine thrombin or certain medications. Clinical presentation varies from asymptomatic laboratory findings to life threatening bleeding. We report the first New Zealand case of cefazolin induced factor V inhibition where we were able to demonstrate temporal relationship. A 65 year old Caucasian man with type 2 diabetes admitted to Dunedin Hospital for right lower leg cellulitis treated with flucloxacilin initially but developed drug induced hepatitis. Coagulation studies were normal and monitored closely. Antimicrobial therapy was switched to cefazolin and after three days he reported prolonged bleeding from finger prick blood test and accidental shaving injury. Coagulation studies became deranged with increased INR, prolonged PT and APTT but normal thrombin clotting time. Further assessment confirmed the presence of factor V inhibitor using Bethesda method. Cefazolin was then changed to vancomycin. Timing of coagulopathy after starting on cefazolin which improved with withdrawal of the antimicrobial therapy suggests that cefazolin was the most likely culprit. The follow up coagulation studies at three weeks showed normal factor V level and coagulation profile. Given cefazolin is a common antibiotic used in our clinical practice, our aim is to raise clinician awareness of this medical problem especially in patient with unexplained bleeding who recently has been started on antibiotics. References: 1. Knöbl P, Lechner K. Acquired factor V inhibitors. Baillieres Clin Haematol 1998; 11:305. 2. Ang AL. Kuperan P, Ng CH, Ng HJ Acquired factor V inhibitor. A problem based systematic review. Thromb Haemost (2009)101:852-859. 3. Franchini M, Lippi G. Acquired factor V inhibitors: a systematic review. J Thromb Thrombolysis (2011)31:449-457.. |