RESUMEN
BACKGROUND Classical hemophilia A, an X-linked recessive disorder, is characterized by an inability to produce factor VIII in normal quantities. This condition, also leading to factor IX deficiency, underpins the bleeding disorder known as hemophilia A. Among the complications of this illness, spontaneous retroperitoneal hematoma is rare but can be associated with congenital coagulopathies such as von Willebrand disease or hemophilia A. This type of spontaneous internal bleeding has been the subject of a limited number of studies. CASE REPORT A 38-year-old man with a known diagnosis of hemophilia A presented to the Emergency Department exhibiting acute pain in the right lower abdomen. A computed tomography scan of the abdomen identified a right-sided retroperitoneal mass, suspected to be a hematoma. Within 7 h after admission, the patient experienced significant drops in the hemoglobin level and platelet count. He was administered packed red blood cells, fresh frozen plasma, and platelet transfusions prior to transfer to the Intensive Care Unit. There, he was treated with factor VIII and recombinant factor VIIa, coupled with stringent monitoring. Following clinical and laboratory findings and stabilization, he was discharged with specific medications, and a follow-up appointment was scheduled. CONCLUSIONS Spontaneous retroperitoneal hematoma in patients with hemophilia A is a rare and grave emergency. This case underscores the need for precise diagnostic approaches, tailored management strategies, and vigilant surveillance to prevent and mitigate the potentially life-threatening complications associated with spontaneous hemorrhage in this population.