Factor XI deficiency (Hemophilia C) is a rare bleeding disorder that was first described in 1953 by Rosenthal et al. in patients who experienced severe bleeding after dental extractions. The estimated prevalence is about 1 in 1 million with increased prevalence among Ashkenazi Jews (8-9%). Patients are generally classified into three categories based on the factor XI levels: severe (<15-20% of normal), intermediate (20- 40%) and mild (>40%). Distinct from hemophilia A and B, FXI deficiency usually presents as post-traumatic bleeding and rarely manifests as spontaneous bleeding.

To report a case of severe Hemophilia C in a 70-year-old woman.

A 70-year-old woman was referred to Fundação Hemominas Juiz de Fora, Brazil due to gingivorrhagia and recurrent epistaxis. She reports having already received blood transfusions due to massive bleeding after surgeries, including cholecystectomy, cesarean section and hysterectomy. The patient is the sixth daughter of a seven children family. Her mother, three siblings and one nephew also have coagulation disorders, unknown Jewish descendancy.

The laboratory study showed normal whole blood count, screening tests for coagulation disorders showed normal platelet count and an increase of activated partial thromboplastin time (aTTP). A plasma dosage of coagulation factors was performed, with results shown in Table 1. With the reduction of factor XI activity levels (3.59%), the increase of aTTP and the normality of other tests, the diagnosis of Hemophilia C was established. A family study was performed with heredogram, shown in Figure 1.

Hemophilia C is a rare bleeding disorder with a wide variability in clinical presentation. Adequate diagnosis is essential to minimize severe hemorrhagic conditions, specially in surgical procedures. Family screening is recommended if a member has FXI deficiency and prevalence may vary in Brazil due to the wide miscegenation.