Never Say Never: Presumed Inherited Factor VII Deficiency Lies in Wait for 17 Years

A previously healthy, 17-year-old girl presented with gross hematuria in the setting of a severely deranged coagulation profile: prothrombin time (PT) > 320 s, international normalized ratio (INR) 15, and activated partial thromboplastin time (aPTT) 59 s. Factor VII (F7) activity (FVII:C) was undetectable. Following administration of two units of fresh frozen plasma (FFP) and phytonadione, her FVII:C increased to 38%, and coagulation profile improved to PT 16.0 s, INR 1.4, and aPTT 30.3 s. With the near-total loss of such a critical coagulation factor, we felt it was exceedingly unusual for a patient to present after 17 years without antecedent bleeding. However, testing ruled out inhibitors, which strongly suggested her deficiency was inherited as opposed to acquired. Moreover, we would not anticipate such dramatic rescue of the coagulation profile with FFP if inhibitors were present, even if they were cross-reactive with F7 and another coagulation factor. And with a vitamin K level near the lower limit of normal, we surmised that a vitamin K insufficiency complicated her severe factor deficiency. As such, while uncommon, patients with severe, inherited deficiency of F7 may not experience their index bleed until many years, even decades, after infancy.