Chilaiditi’s Syndrome with Interposed Sigmoid Colon Mimicking Traumatic Pneumoperitoneum

1Department of Internal Medicine; 2Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan Correspondence: Dr Chang-Hsien Liu, No. 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan. Telephone 886-2-87927244, fax 886-2-87927245, e-mail cute610627@yahoo.com.tw Received for publication May 3, 2013. Accepted May 6, 2013 Case presentation A 61-year-old man experienced a contusion on the right hypochondrium in a traffic accident. He was immediately taken to the emergency department and presented with severe pain over the contusion site. His surgical history was unremarkable. On arrival, physical examination revealed decreased breathing sounds in the right lower lung area on auscultation. Distention, hypertympanic percussion and local tenderness over the right upper quadrant of abdomen were also observed. A posteroanterior chest radiograph revealed elevation of the right hemidiaphragm with concerning features for subphrenic free air as well as fracture of right fifth to eighth ribs (Figure 1A). A computed tomography scan of the abdomen with coronal reconstruction revealed hepatodiaphragmatic interposition of the dilated sigmoid colon (Figure 1B). No evidence of pneumoperitoneum was identified. Conservative treatment with oxygenation, chest care and pain control was performed. After the medical therapy, the patient was discharged uneventfully.