RÉSUMÉ
BACKGROUND: Portal venous gas has been considered as a radiological sign requiring urgent operative intervention; however, the reports concerning portal venous gas associated with favorable outcome are recently increasing. CASE PRESENTATION: We describe a 9-month-old boy with acute onset high fever and vomiting. The ultrasonography demonstrated micro-gas bubbles continuously floating in the intrahepatic portal vein. Contrast-enhanced CT, performed 1 h later from echography, revealed a whirlpool sign suggesting an intestinal malrotation with midgut volvulus, but with no signs of residual intrahepatic gas. Operative findings showed a mild volvulus with neither congestion nor ischemic change of the twisted bowel. Detorsion and Ladd's procedure were completed laparoscopically. CONCLUSIONS: Transient portal venous gas bubbles may be generated even in the mild intestinal volvulus with no bowel ischemia. Ultrasonography can be a sensitive detector to visualize such small amounts of gas.