A population based, unselected, consecutive cohort of patients with acquired haemophilia A.

Previous studies in acquired haemophilia A have reported on cohorts of patients referred to specialist centres or were retrospective surveys of specialist centre experience. This may have resulted in the literature representing a more severe group of patients than seen in routine haematological practice. We report on a consecutive, unselected cohort of all patients in south and west Wales who presented with acquired haemophilia A between 1996 and 2002. There were 18 patients, an incidence of 1.34/million/year. Compared with previously reported cohorts our patients were older, with a median age of 70 years, and less likely to have an underlying diagnosis (27%). The bleeding phenotype was less severe, with only 27% having life or limb threatening bleeds and 41% required no haemostatic treatment. One patient died of bleeding, but three died of complications related to immunosuppression. Response to immunosuppression was high compared with other series, with 88% of treated patients attaining an undetectable inhibitor and normal factor VIII level. These data suggest that previously reported cohorts may represent more severely affected patients and, whilst guidelines for treatment based on these assumptions may be valid for severely affected patients, they may not be universally applicable.