An unusual case of gallstone ileus 35 years post-cholecystectomy masked by an incisional hernia.

Gallstone ileus is an uncommon cause of mechanical bowel obstruction in patients with cholecystitis and gallstones who develop a fistula over time. In the post-cholecystectomy patient, the presence of gallstone ileus is extremely rare; these patients have different pathophysiological pathways, such as a spilled gallstone that subsequently erodes into the bowel, subtotal cholecystectomies, and diverticulae that can hold a gallstone for hidden several years. In these patients, the clinical presentations are unique because of their rarity and because the gallbladder had been previously removed.