Severe Congenital Factor X Deficiency as a First Case Report in Cambodia.

Background: Factor X (FX) deficiency is a rare autosomal recessive inherited bleeding disorder, with an estimated prevalence of approximately 1 in 1,000,000 individuals. According to the most recent data published by the World Federation of Hemophilia, no cases of FX deficiency have been reported in Cambodia to date. Case Report: A 14-year- and 7-month-old Cambodian boy presented with recurrent gum bleeding. His medical history was notable for multiple hematomas, joint ankylosis, and blue sclera. He was born to second-degree consanguineous parents, with no known family history of bleeding disorders. Laboratory evaluation revealed prolonged prothrombin time (PT) and activated partial thromboplastin time (APTT) and severely reduced FX activity (< 1%), consistent with a diagnosis of severe congenital FX deficiency. Bleeding was successfully managed with fresh frozen plasma, initially administered at 15 mL/kg, followed by maintenance doses of 5 mL/kg twice daily. Conclusion: FX deficiency, though rare, should be considered in the differential diagnosis of pediatric patients presenting with recurrent gingival or mucocutaneous bleeding in conjunction with prolonged PT and APTT. This consideration is particularly important in resource-limited settings such as Cambodia, especially in children born to consanguineous parents and after more common coagulopathies have been excluded. In low-resource settings, where FX concentrates are often unavailable or unaffordable, fresh frozen plasma remains the primary treatment option.