Iliac Artery Aneurysm with Primary Arteriocolic Fistula: An Unusual Cause of Lower Gastrointestinal Hemorrhage - Abstract
Arteriocolic fistula is a rare but life-threatening condition. We report the case
of a 70-year-old man who presented with passage of bloody stools and intolerable
abdominal pain. Esophagogastroduodenoscopy and colonoscopy failed to identify
the source of the bleeding. Contrast-enhanced abdominal computed tomographic
scans showed an aneurysm arising from the left common iliac artery with close
adhesion between the aneurysm and adjacent sigmoid colon, but no extravasation
was detected. After an episode of severe abdominal pain with massive bleeding,
emergency laparotomy revealed that the aneurysmal wall was closely adhered to the
sigmoid colon with fistula formation. Iliac arterial aneurysm with arteriocolic fistula was
diagnosed. The aneurysm was excised, and femoral-femoral bypass grafting was done.
No bleeding recurred during 6 months of follow-up. Although bleeding from a primary
iliac arteriocolic fistula is rare, it should be considered in the differential diagnosis
of lower gastrointestinal bleeding, especially in patients with severe abdominal pain.