Radiolucent gallstone ileus causing proximal small bowel obstruction: A case report.

Gallstone ileus occurs when gallbladder stones erode and become lodged in the small bowel, thereby causing obstruction. These stones usually impact the terminal ileum because of its narrow lumen; however, they can also be found in less common locations, as observed in our case. The presence of pneumobilia can indicate gallstone ileus even without visible radiopaque stones because not all gallstones are detectable on computed tomography (CT). A 74-year-old woman presented to the emergency department with severe right upper quadrant pain that started 1 week previously and became more aggressive associated with fever, leukocytosis, and vomiting. The pain was colicky, intermittent, and aggravated by movement but did not radiate. Further imaging was requested to investigate the cause of the pain, which revealed evidence of proximal small bowel obstruction due to radiolucent gallstone ileus. Radiolucent gallstone ileus is a rare but serious condition requiring prompt surgical intervention. The presence of pneumobilia can indicate gallstone ileus even when the stones are not visible on CT. Large stones can cause blockages in the proximal small bowel. The ability of radiological imaging to detect gallstones varies according to their composition.