Ultrasound and computed tomography findings of hepatic portal venous gas associated with acute appendicitis in a paediatric patient: A case report

Introduction: Hepatic portal venous gas is a rare and life-threatening condition characterised by the presence of gas in the portal vein. Hepatic portal venous gas is frequently associated with intestinal ischaemia and necrosis. We present the case of a paediatric patient with acute appendicitis with hepatic portal venous gas detected using ultrasonography. Case report: A 5-year-old boy was admitted to our hospital with a respiratory tract infection. The boy started vomiting on day 2 of hospitalisation. He did not complain of any symptoms due to developmental retardation. We performed bedside point-of-care ultrasound, which detected hepatic portal venous gas, although the appendix could not be detected due to an acoustic shadow associated with bowel gas. Contrast-enhanced computed tomography revealed perforated appendicitis and pneumatosis intestinalis associated with paralytic ileus. An emergency laparoscopic appendectomy was performed. He was discharged on day 25 of hospitalisation after antibiotic therapy. Discussion: The present case suggests that the mechanism of hepatic portal venous gas was paralytic ileus, which caused gas-forming bacterial proliferation. The gas produced by bacteria and/or the gas-forming bacteria entered the bowel wall, which caused pneumatosis intestinalis. The bubbles in the intestinal wall floated in the portal system and were detected as hepatic portal venous gas. Perforated appendicitis and paralytic ileus seemed to be caused by a delayed diagnosis of appendicitis. The point-of-care ultrasound examination was useful for detecting hepatic portal venous gas and for helping establish the diagnosis of appendicitis. Conclusion: Hepatic portal venous gas is a rare finding associated with appendicitis in children. In addition, point-of-care ultrasound is useful for detecting hepatic portal venous gas in paediatric patients.