On day 5, her abdomen was distended, and she developed respiratory distress and was intubated. The umbilical venous catheter (UVC) was removed because of clinical suspicion of necrotizing enterocolitis. A radiograph of the abdomen was obtained (Figure 1). An ultrasound examination of the abdomen showed echolucency in both flanks indicating free fluid. The kidneys were not identified, but the liver and spleen were normal. Pigtail catheters (4F) were inserted by ultrasound guidance into the flank regions bilaterally. Ninety milliliters of opalescent, blood-stained fluid was aspirated, 50 mL from the right flank and 40 mL from the left flank. Contrast medium was injected via the catheters (Figure 2). Ultrasound following this procedure showed normal kidneys. A laparotomy was performed and showed no necrotizing enterocolitis, perforated viscus, or any other intraperitoneal abnormality. The infant recovered, and findings from ultrasound examination of the abdomen prior to discharge on day 53 was normal.