Abstract
A 70-year-old woman was referred to our hospital with a two-month history of generalized erythematous bullous skin eruptions that were unresponsive to 25 mg/day of oral prednisolone (PSL) and discontinuation of dipeptidyl peptidase-4 (DPP-4) inhibitor, which had been administered for diabetes. She had been diagnosed as having bullous pemphigoid based on a high serum level of antiBP 180 antibody and histopathological findings. During treatment with an increased dose of oral PSL (45 mg/day), bleeding tendency, such as subcutaneous hemorrhage, hemorrhagic bullae, oral submucosal hemorrhage, and black stool, developed. A diagnosis of acquired hemophilia A (AHA) was made from laboratory results as she had normal PT, prolonged APTT, cross-mixing test with an inhibitor pattern, detection of VIII inhibitor, a reduced activity level of factor VIII, and normal von Willebrand activity. Treatments with oral cyclophosphamide and clotting factor concentrates, such as intravenous activated prothrombin complex concentrates (APCC), along with the increased PSL (50 mg/day) seemed to have had little effect on AHA at first ; however, repeated APCC administration improved AHA within five months from the onset of AHA. Both BP and AHA showed no signs of recurrence after 15 months through the course of PSL tapering. Human leukocyte antigen (HLA) typing revealed that she carried HLA-DQB1*03:01, which is known to have an association with DPP-4 inhibitor-related BP. Among AHA, 1.4 to 4.5% of cases are associated with skin disease, and BP is one of the most common complications for AHA. Although our patient developed AHA during systemic PSL therapy and showed treatment-resistance at first, her condition remitted by five months of repeated APCC administration. AHA is rare but can be a fatal complication during the treatment of BP. Early detection of bleeding tendency and appropriate consultation to specialists, such as hematologists, are required. Skin Research, 21 : 162-169, 2022
