Chilaiditi syndrome/sign

Clinical History

A surgical senior house officer (SHO) comes to the radiology department for an opinion regarding a chest radiograph of a 58-year-old male patient with vague chest and abdominal pain. The SHO wants you to comment on the radiograph and advice regarding further investigation if needed.

Imaging Findings

The chest radiograph (Fig. 1) shows air beneath the right hemidiaphragm. No definite haustral markings are noted. The upper border of the liver is pushed downwards. Another notable finding is that the diagrammatic radioopaque line appears thickened, which is due to apposition of colonic wall and hemidiaphragm. The CT images (Fig. 2a-e) clearly show the interposition of the hepatic flexure of colon between the liver and the diaphragm. There are no features of volvulus.

Discussion

The term Chilaiditi syndrome was described by Dr. Demetrius Chiladaiti in 1910. He described it as an asymptomatic interposition of the bowel (usually hepatic flexure of the colon) between the liver and the (right) hemidiaphragm. The findings were seen in 0.1-0.25% of chest X-rays. They are mostly incidental, more common in men and present intermittently [1].
Factors contributing to its occurrence include: Absence of normal suspensory ligaments of the transverse colon, abnormality or absence of the falciform ligament, redundant colon as it might be seen with chronic constipation or in bedridden individuals and paralysis or eventration of the right hemidiaphragm. Liver cirrhosis can cause the hepatic flexure of the colon to move into the sub-diaphragmatic space as there is volume loss of the liver. The syndrome may involve abdominal pain, constipation, vomiting, respiratory distress and anorexia. Chilaiditi’s syndrome is important because it is a great simulator of pneumoperitoneum and may cause panic in the ward rounds when seen on the radiograph on a seemingly healthy patient.
Look for the presence of haustral folds and the thickened diaphragmatic line. Left lateral decubitus abdominal films may help in this distinction [1]. If the patient shows clinical features of peritonitis, then a CT is warranted as concomitant pneumoperitoneum or a volvulus has to be excluded. Interposition of the colon may also be seen beneath the left hemidiaphragm in patients who have undergone splenectomy.
Once interposition of colon is confirmed, further investigation is required. It is always a good idea to consult with an experienced radiologist to differentiate pseudopneumoperitoneum from true pneumoperitoneum. These radiographs are also perfect for teaching sessions.

Differential Diagnosis List

Final Diagnosis

Hepatodiaphragmatic interposition of the intestine, also called Chilaiditi's syndrome

URL:	https://www.eurorad.org/case/12066
DOI:	10.1594/EURORAD/CASE.12066
ISSN:	1563-4086