Subsequently occurring bilateral iliopsoas hematoma: a case report.

BACKGROUND Spontaneous bilateral iliopsoas hematomas is a rare complication after anticoagulant therapy. Furthermore, the onset of bilateral iliopsoas hematoma is unknown because the causes are unclear. CASE PRESENTATION A 65-year-old man on anticoagulant therapy after mechanical aortic valve replacement was admitted after presenting with severe pain in the left flank and abdomen. Abdominal CT revealed a large left-sided iliopsoas hematoma with extravasation. Fresh frozen plasma was transfused due to prolonged prothrombin time. Transarterial embolization was successfully performed. During the hospital stay, follow-up abdominal CT was performed and a small right-sided iliopsoas hematoma was detected. This was closely observed and an intervention was not performed, as the patient was asymptomatic. The final CT prior to discharge revealed a reduction in size of each hematoma. CONCLUSIONS Spontaneous bilateral iliopsoas hematoma can be developed subsequently. Patients with unilateral iliopsoas hematoma should be closely monitored for development of bilateral iliopsoas hematoma.