Congenital combined deficiency of coagulation factor V (FV) and factor VIII (FVIII) (F5F8D) is a rare autosomal recessive bleeding disorder caused by mutations in lectin mannose-binding type 1 (LMAN1) or multiple coagulation factor deficiency 2 (MCFD2) encoding chaperone molecules involved in the intracellular transport of FV and FVIII. Here, we report a case of F5F8D in an elderly patient diagnosed with hematoma after a right thigh injury. A 71-year-old male had a history of abnormal bleeding after tooth extraction and cholecystectomy. The patient injured his right thigh with a kitchen knife; he was urgently hospitalized to a referral hospital 8 days later due to the occurrence of hematoma at the same site. Owing to prolongation of the coagulation time (PT 16.1 s, 1.72; APTT, 66.1 s), he received hemostatic treatment with fresh-frozen plasma. He was then referred to our hospital for examination of PT and APTT prolongation. FV and FVIII activities were moderately decreased to about 15%, and no inhibitor was detected. Whole-exome sequencing identified a previously reported homozygous nonsense mutation in LMAN1, revealing F5F8D in the proband. In this case, FFP infusion alone was not sufficient for increasing coagulation factor activities. Definitive diagnosis of F5F8D provides him with the treatment option with FVIII concentrates.
Keywords: F5F8D; Familial multiple coagulation factor deficiency; LMAN1.