Acquired hemophilia A secondary to cholangiocarcinoma: A case report and literature review.

Acquired hemophilia A (AHA) is a rare autoimmune bleeding disorder. Its occurrence secondary to hepatobiliary malignancies is even rarer, and without timely diagnosis and treatment, the mortality rate is extremely high. There is a need to raise awareness of this disease. This report describes a case of a 70-year-old female patient diagnosed with AHA 2 months after surgery for cholangiocarcinoma, admitted to the Second Affiliated Hospital of Bengbu Medical College in October 2022. The patient presented with subcutaneous hematoma in both lower limbs. Coagulation function tests showed a markedly prolonged activated partial thromboplastin time (APTT) of 74.5 seconds, with no correction in the APTT mixing test. Coagulation factor assays revealed a severely reduced coagulation factor VIII activity (FVIII:C) of 0.3%, and an inhibitor titer of 25.6 BU/mL was detected. After ruling out other potential causes, the patient was diagnosed with cholangiocarcinoma-associated AHA. With chemotherapy to control the primary tumor, alongside hemostatic and immunosuppressive therapy for inhibitor eradication, AHA was brought under control. The patient had no further coagulation abnormalities or bleeding, enabling timely and full-course chemotherapy for cholangiocarcinoma and significantly improving survival and quality of life. Therefore, in patients with malignancies who present with spontaneous bleeding or unusual bleeding following surgery, trauma, or invasive procedures, clinicians should be alert to the possibility of secondary AHA. Timely diagnosis and treatment can significantly improve prognosis.