-Case Reports-

Relapse of Acquired Hemophilia A after COVID-19 Infection

Atsushi Marumo^1,2, Hisae Sugihara³, Ikuko Omori^1,2 and Eriko Morishita⁴

¹Division of Internal Medicine, Fussa Hospital, Tokyo, Japan
²Department of Hematology, Nippon Medical School, Tokyo, Japan
³Division of Clinical Laboratory, Fussa Hospital, Tokyo, Japan
⁴Department of Clinical Laboratory Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Faculty of Health Sciences, Kanazawa University, Kanazawa, Japan

Acquired hemophilia A (AHA) is a rare disease in which an autoantibody causes bleeding by interacting with and inhibiting the coagulation activity of endogenous factor VIII (FVIII). Most cases of AHA are idiopathic; known causes include autoimmune diseases, malignant tumors, pregnancy, drugs, and viral infections. An 86-year-old man was diagnosed with AHA based on the following results: an activated partial thromboplastin time (aPTT) extension of 130.7 seconds, presence of an inhibitor pattern in a mixing study, an endogenous factor VIII (FVIII) level of <1%, and an FVIII inhibitor titer of >5.1 Bethesda units (BU). The activity of von Willebrand factor (vWF) was diminished (<10%), which was considered a complication of acquired von Willebrand syndrome (AVWS). The patient was started on prednisolone, and the inhibitor level eventually became negative. vWF values also became normal. However, 1 year later, he was hospitalized for treatment of coronavirus disease 2019 (COVID-19). Blood testing showed an aPTT extension of 110.5 seconds, FVIII level of 4%, and FVIII inhibitor titer of 0.8 BU; thus, a relapse of AHA was diagnosed. After administration of corticosteroid and remdesivir, he recovered from COVID-19 and AHA. The inhibitor level became negative on the 9th day of admission. Several studies have implicated COVID-19 infection and vaccination in AHA. We recommend that aPTT be measured when patients with AHA are infected with SARS-CoV2, to confirm AHA relapse.

J Nippon Med Sch 2023; 90: 474-479

Keywords
COVID-19, acquired hemophilia A, acquired von Willebrand disease, factor VIII, mixing study

Correspondence to
Atsushi Marumo, MD, Division of Internal Medicine, Fussa Hospital, 1-6-1 Kamidaira, Fussa, Tokyo 197-8511, Japan
a.agassi2112@gmail.com

Received, August 27, 2022
Accepted, November 10, 2022