Acquired haemophilia A (AHA) is a rare, autoimmune disease, presenting as sudden haemorrhages without any personal or family history. Anti-factor VIII (FVIII) is the most commonly recognised autoantibody resulting in decreased factor activity. The aetiology and pathophysiology of these antibodies remains unclear. Approximately 50% of reported cases are idiopathic; the rest are associated with other conditions, mainly underlying malignancies, autoimmune diseases (eg rheumatoid arthritis (RA), systemic lupus erythematosus), drug administration and postpartum period. A 74-year-old woman presented to our institution with haematochezia and haematuria. She had a medical history of cervix carcinoma; total abdominal hysterectomy and bilateral salpingo-oophorectomy with postoperative chemoradiotherapy was performed in 2011. She had also been followed up for 20 years for deforming and severe RA, which was in low-disease activity with methotrexate and corticosteroid. Laboratory investigations for abnormal bleeding revealed prolongation of activated partial thromboplastin time (APTT). APTT prolongation was not corrected by 50:50 plasma mixing studies, and a confirmatory factor assay demonstrated FVIII deficiency (1.4 IU/dL; normal range 50-150 IU/dL). Positive FVIII antibodies on Bethesda testing confirmed a diagnosis of AHA. A rectosigmoid mass and fistula between rectum and bladder were discovered by computed tomography (CT). Bleeding was controlled with recombinant activated factor VII (rFVIIa) after two weeks. Eradication of the inhibitor was achieved with high-dose pulse methylprednisolone for two days and then 2mg/kg daily over four weeks.