A 71-year-old woman presented to the ED with abdominal pain of
one week’s duration. The pain was midepigastric in location
and radiated upwards. It was associated with nausea, but unrelated to
food intake. She had seen another physician two days earlier who
prescribed ranitidine. The pain continued and was now associated
with vomiting. She also felt “bloated.”
The patient had diabetes and was taking glyburide. She had a
hysterectomy many years earlier.
On examination, she was an elderly woman in moderate discomfort.
Vital signs were: blood pressure 110/72 mm Hg, pulse 80
beats/min, respirations 18 breaths/min, temperature
99.0° F (rectal).
Her abdomen was soft with normal bowel sounds. It appeared slightly
distended. There was mild tenderness in the midepigastrium and right
upper and lower quadrants, but no rebound tenderness or guarding.
Her blood test results were normal including a complete blood
count and chemistries, aside from a blood glucose level of 179 mg/dL.
- The abdominal radiograph provides an exact anatomical
diagnosis of the patient’s disorder (Figure 1).
Radiography was performed in this patient for suspected bowel
obstruction. It shows the classic Rigler’s
triad of gallstone ileus: (1) pneumobilia; (2) small bowel
obstruction; and (3) an ectopic gallstone (Rigler et al. 1941) (Figure
2). Rigler’s triad is, in fact, seen only in a minority
of cases of gallstone ileus (25%).
A. Pneumobilia. Gas in the gallbladder (arrow) and
cystic duct (arrowhead). B. Ectopic gallstone. A thin layer of gas surrounds the gallstone (arrow).
Gallstone ileus is a disease of
the elderly. Despite being called “ileus,” it
is actually a type of mechanical small bowel obstruction. Cholelithiasis
and chronic cholecystitis results in formation of an inflammatory
fistula between the gallbladder and the adjacent duodenum (75%)
or transverse colon (20%). The gallstone is expelled into
the intestine and, if large (3 cm in diameter or greater), the gallstone may
lodge in an area of intestinal narrowing, usually at the ileocecal
valve, causing bowel obstruction (Figure 3).
Pathogenesis of gallstone ileus.
(A) Chronic cholecystitis due to
a gallstone causes inflammatory fistula formation to the adjacent bowel
(most commonly the duodenum). (B) The
gallstone is expelled into the intestine across the biliary-enteric
fistula. (C) The gallstone migrates through
the intestine until it becomes lodged at an area of narrowing (usually
the ileocecal valve). This causes a mechanical small bowel obstruction.