A 56-year-old man arrived at a New York emergency department with one day of intermittent left-sided abdominal pain, nausea, and a single episode of vomiting. His CT scan showed a 3.3-centimeter stony mass wedged in the terminal ileum, choking off most of the bowel. The object had a dark center wrapped inside a dense, ridged outer shell. The reading team's impression was gallstone ileus.
It was a peach pit.
Surgeons affiliated with the Icahn School of Medicine at Mount Sinai opened the bowel, extracted the object, and measured it at 4 cm by 3 cm, then published the case in BMJ Case Reports. Their point was not that anyone blundered. It was noted that on cross-sectional imaging, a swallowed fruit pit and a migrated gallstone can look nearly identical, even though the two findings imply completely different underlying diseases.
Why a Pit and a Gallstone Read the Same
Gallstone ileus is uncommon, accounting for roughly 1% to 3% of all mechanical bowel obstructions. It skews heavily toward women and patients over 65, and it happens when repeated inflammation erodes a channel between the gallbladder and the gut, letting a stone escape and jam at a narrow point. Stones larger than about 2.5 centimeters are the usual culprits, and the terminal ileum and ileocecal valve are where they tend to stop.
Radiologists look for Rigler's triad: bowel obstruction, air inside the biliary tree, and a visible ectopic stone. When all three appear, the diagnosis is close to settled. The trouble starts when only the third element shows up, which is often the case, since only about 15% of gallstones carry enough calcium to appear radiopaque at all.
Pits from peaches, nectarines, apricots, and plums have a hard, ridged husk around a softer kernel. On CT, that architecture produces a bright rim and a darker core, the same pattern a layered gallstone can produce. Without air in the bile ducts or a visible fistula, what the scanner sees is simply a dense round thing sitting where nothing round should be.
An Apricot Shell That Fooled a Lithotripter
The confusion runs in both directions, and one Italian case shows how far it can go.
Gastroenterologists at Sant'Anna University Hospital in Ferrara treated a 49-year-old woman with a partial bowel obstruction. She had previously had part of her cecum and terminal ileum removed, leaving a narrowed junction between small and large bowel. Plain films and CT pointed to gallstone ileus. Rather than operate, the team dilated the narrowed segment with a balloon, removed two stones with a retrieval basket, and broke up a third, larger stone using extracorporeal shock-wave lithotripsy.
Then, unexpectedly, they retrieved an apricot shell. It had been sitting above the narrowing, contributing to the blockage, and it had been visible on X-ray during the lithotripsy session because the team had taken it for another stone. The patient denied eating apricots for months beforehand. She recovered without complications and remained symptom-free six months later. Her team reported it in the Journal of Medical Case Reports, arguing that colonoscopy can sometimes provide diagnosis and treatment in a single session.
A separate report describes stone fruit acting alone. A 67-year-old man presented with a day of lower abdominal pain, nausea, and vomiting after a recent admission written off as gastroenteritis. CT showed a 25-millimeter dense lesion in the distal small bowel. Laparoscopy could not find it, so the surgeons converted to open surgery and located a nectarine pit near the ileocecal junction, along with a separate perforation higher up in the ileum. He could not recall eating a nectarine. His wife mentioned they had been eating them all week.
Who Actually Ends Up in the Operating Room
Most swallowed objects are a non-event. A 2026 case report and literature review in Frontiers in Surgery reports figures of roughly 80% passing spontaneously, about 20% requiring endoscopic removal, and around 1% requiring surgery.
The people who run into trouble tend to be older. That review notes accidental ingestion is most common in children and the elderly, though it also happens to adults who eat quickly or chew poorly. Among older patients, reduced chewing function and loose or ill-fitting dentures increase the risk of swallowing hard foods without noticing. Objects tend to lodge at sphincters, narrowings and sharp bends, with the stomach and duodenum together accounting for a large share, and at pre-existing trouble spots such as diverticula, adhesions and surgical joins.
Case reports are not risk estimates. Nothing in this literature suggests that eating peaches or apricots is dangerous, and none of these papers measure the frequency of pit impaction. What they establish is that the possibility belongs on the differential.
What This Changes at the Bedside
The practical takeaway is narrow and useful: an ovoid stony body in the bowel should prompt a question about recent meals, not just about gallbladder history. A patient who remembers eating a whole apricot provides information no scanner can, and, as the nectarine case shows, a spouse sometimes provides it when the patient cannot.
The distinction is not academic. Gallstone ileus often carries a recommendation to address the underlying biliary fistula, sometimes in a second operation. A fruit pit implies no biliary disease at all. In the Ferrara case, imaging afterward found no fistula and no air in the bile ducts, which changed how the team thought about follow-up surgery.
Anyone with persistent abdominal pain, repeated vomiting, or an inability to pass stool or gas should seek medical evaluation rather than wait it out.
Key Questions Answered
What is gallstone ileus? A mechanical bowel obstruction caused by a gallstone that has migrated into the intestine, usually through an abnormal channel between the gallbladder and the gut. It represents roughly 1% to 3% of mechanical bowel obstructions.
How can a fruit pit be mistaken for a gallstone? Stone fruit pits have a hard, ridged husk around a softer kernel, which, on CT, produces a bright rim and a darker center, similar to a layered gallstone. Without additional signs such as air in the bile ducts, the two can look alike.
How common is this? Rare. Fruit pit impaction appears in the medical literature as individual case reports rather than as a measured incidence. Published cases involve peach, nectarine, and apricot pits.
Does swallowing a pit usually cause harm? No. Published figures indicate roughly 80% of swallowed objects pass without intervention, about 20% need endoscopic removal, and around 1% require surgery.
Who is most at risk of an ingested object causing obstruction? Older adults, people with reduced chewing function or loose dentures, those who eat quickly, and patients with narrowed bowel from prior surgery, diverticular disease, or adhesions.
What symptoms should prompt medical attention? Persistent abdominal pain, repeated vomiting, abdominal distension, or an inability to pass stool or gas. These warrant urgent evaluation regardless of suspected cause.
