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Challenges in management of unusual acquired factor V deficiency: A case report
Kiyoshi Takemoto1,2, Osamu Hamada2, Koichi Kitamura2,3
1Department of General Internal Medicine, Nara City Hospital, Nara.
Rationale:
Acquired inhibitors of coagulation are antibodies that either inhibit the activity or increase the clearance of a clotting factor. Acquired factor V deficiency is a rare coagulation disorder, and it can sometimes be life threatening.
Patient Concerns:
We describe a case of a 90-year-old Japanese male with acquired factor V deficiency. He was previously misdiagnosed with congenital factor V deficiency when he presented with hemoptysis and a negative factor V inhibitor test result at a different hospital 5 years earlier. Coagulopathy recurred with ecchymosis when he sustained a bruise after falling on a bush.
Diagnosis:
Although the factor V inhibitor test result was negative and a mixing study suggested a deficiency pattern, we diagnosed the patient with acquired factor V deficiency on the basis of no history of bleeding diathesis, a lack of response to multiple fresh frozen plasma transfusion, and clinical response to corticosteroid therapy.
Interventions:
Intravenous methylprednisolone was administered at 500 mg/day for 3 days, followed by oral prednisolone at 1 mg/kg/day.
Outcomes:
Coagulation test results improved and symptoms resolved 2 weeks after corticosteroid administration.
Lessons:
This case report suggests that clearance-facilitating antibodies exist without the presence of neutralizing inhibitors. When patients present with coagulation factor V deficiency in the absence of coagulation inhibitors, acquired factor V deficiency should also be considered.
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