History A 24-year-old woman presented to the emergency department with a history of acute urinary retention, gross hematuria, and left flank pain for 2 days. Past history was unrevealing. Her last menstrual period occurred 2 weeks prior to presentation. At physical examination, she had a temperature of 38.4°C. A palpable mass was noted in the suprapubic region, and a second mass was palpated in the left upper quadrant. Blood work revealed a hemoglobin level of 4.7 g/dL (normal range, 11.5-15.5 g/dL). Her coagulation profile and white blood cell count were within normal limits. Ultrasonography (US) of the abdomen and pelvis was performed and was followed by contrast material-enhanced (80 mL of iopamidol) computed tomography (CT) of the chest, abdomen, and pelvis. Magnetic resonance (MR) imaging of the abdomen and pelvis also was performed.