Spontaneous rectus sheath hematoma caused by vitamin K antagonists overdose: a case report and a review of the literature.

Introduction: Spontaneous rectus sheath hematoma (RSH) is a rare but potentially life-threatening complication of anticoagulant therapy, particularly with vitamin K antagonists (VKAs). Its clinical presentation can mimic other acute abdominal conditions, posing diagnostic and therapeutic challenges. Case Presentation: We report the case of a 78-year-old woman with a history of mitral valve replacement and atrial fibrillation treated with a VKA, who presented with acute abdominal pain, swelling, and dizziness. On examination, a tender mass was palpable in the right lower quadrant. Laboratory evaluation revealed severe anemia (hemoglobin 4.7 g/dL) and an elevated INR of 5.2. Computed tomography (CT) confirmed a large right-sided rectus sheath hematoma (12 × 7 cm) with contrast extravasation but no intraperitoneal extension. Management included immediate cessation of VKA therapy, reversal of anticoagulation with intravenous vitamin K and fresh-frozen plasma, and transfusion of two units of packed red blood cells. The patient remained hemodynamically stable, and serial imaging demonstrated gradual hematoma regression. She was discharged with outpatient follow-up and anticoagulation management. Discussion: This case highlights the importance of considering RSH in anticoagulated patients presenting with acute abdominal pain. Risk factors include advanced age, female sex, comorbidities, and supratherapeutic anticoagulation. CT imaging is the diagnostic modality of choice. Most cases are managed conservatively, while interventional radiology or surgery is reserved for unstable patients or expanding hematomas. Conclusion: Early recognition of VKA-induced RSH and prompt management can prevent serious complications. Clinicians should monitor anticoagulation closely and educate patients to minimize bleeding risks.