Case Report: Atypical presentations of neonatal and infantile hemophilia B

Hemophilia B is an X-linked recessive bleeding disorder caused by deficiency or dysfunction of factor IX. It typically presents with spontaneous or trauma-induced bleeding, hemarthrosis, and soft tissue hematomas. We report three cases—two severe neonatal and one moderate infantile case—with atypical presentations: intra-abdominal hemorrhage with hepatic hematoma, a scrotal mass mimicking testicular torsion, and intracranial hemorrhage. None of the patients had a family history of bleeding disorders, and diagnoses were made after these significant bleeding episodes. These cases underscore the importance of considering congenital bleeding disorders in neonates and infants, especially males, who present with unexplained severe bleeding episodes in the absence of trauma or family history. Early recognition, preconception genetic counseling to identify the risk of bleeding disorders in parents, and individualized prophylactic approaches are essential to improve outcomes.