Acquired coagulation inhibitors result from immune-mediated depletion or inhibition of a coagulation factor. Inhibitors are most commonly directed against factor VIII (FVIII)
and von Willebrand factor (VWF) and inhibitors against other coagulation factors are only occasionally reported.
Since the publication of previous guidelines (Laffan et al, 2004; Pasi et al, 2004; Hay et al, 2006) substantial new data has been published on acquired FVIII inhibitors, necessitating updated guidelines. The rarity of acquired inhibitors to other coagulation factors means that limited information is available to guide management and the treatment strategies suggested are necessarily by consensus and often extrapolated
from data derived from FVIII inhibitors. Inhibitors to VWF will not be covered because a revised von willebrand disease (VWD) guideline is in preparation (Laffan et al, 2004; Pasi et al, 2004).

First published online 25 July 2013
British Journal of Haematology, 2013, 162, 758–773 doi: 10.1111/bjh.12463