Retroperitoneal Hematoma in a Patient with Advanced Chronic Kidney Disease Receiving Warfarin Therapy.

A 73-year-old man with chronic kidney disease stage G5 was admitted to our hospital because of a worsening kidney dysfunction. He had undergone prosthetic valve replacement of the mitral valve 5 years previously and was currently taking warfarin. He showed excessive anticoagulation on admission, with a prothrombin time-international normalized ratio (PT-INR) of 3.91. The use of warfarin was ceased and PT-INR decreased to 2.1. Since the patient would need renal replacement therapy, he underwent arteriovenous fistula surgery for hemodialysis access on day 16. However, on day 18, he suddenly complained of lumbago and went into shock. His blood pressure dropped to 73/49 mmHg, and the hemoglobin level fell to 4.9 g/dL. Computed tomography revealed a huge retroperitoneal hematoma. Emergent lumbar artery embolization was performed on two consecutive days; however, the bleeding persisted, with subsequent development of abdominal compartment syndrome with impaired respiratory and cardiovascular function, and the patient died. Autopsy revealed a hematoma measuring 30×20×20 cm involving the psoas muscle and external iliac artery; the hematoma was covered with fibrous tissue instead of muscle. The psoas muscle is supplied by the internal iliac artery; however, a collapsed artery could not be confirmed in our patient. The closest major artery to the hematoma was located at the intersection of the psoas muscle and the external iliac artery. All arteries showed severe atherosclerosis. In patients with advanced chronic kidney disease, anticoagulant therapy should be administered carefully, and the etiology of retroperitoneal hematoma should be further investigated.