What are the clues to gallstone ileus when stones don't show up on scans? A case presentation and literature review.

Gallstone ileus is a rare yet significant cause of mechanical bowel obstruction, particularly in elderly patients. This condition arises when gallstones migrate into the gastrointestinal tract through a cholecystoenteric fistula, often due to chronic inflammation. Despite medical advancements, gallstone ileus remains associated with high morbidity and mortality rates due to delayed diagnosis and nonspecific symptoms. The clinical presentation typically includes intermittent nausea, vomiting, abdominal pain, and constipation, which can obscure the diagnosis. Advanced imaging techniques, especially computed tomography (CT), are crucial for identifying key diagnostic features such as pneumobilia, ectopic gallstones, and signs of bowel obstruction. Gallstone ileus should be considered in any case of small bowel obstruction, even if CT imaging is inconclusive, as gallstones can be radiolucent. Indirect clues like pneumobilia and dilated small bowel loops can lead to the diagnosis. Effective management of gallstone ileus requires prompt surgical intervention to remove the obstructing gallstone and restore bowel patency. The primary surgical procedure is enterolithotomy, although additional procedures such as cholecystectomy and fistula repair may be necessary depending on the patient's condition and intraoperative findings. The choice of surgical approach should be individualized, considering the patient's overall health and the specific characteristics of the obstruction. Early recognition and timely surgical management are essential to prevent complications and improve patient outcomes.