A 63-year-old woman, with a history of cirrhosis and high blood pressure, was referred to our emergency department with lower abdominal pain and hematochezia. She had not undergone any previous abdominal surgery or trauma. The abdominal examination was normal and laboratory tests demonstrated a hemoglobin value of 98.60 g/dl. Colonoscopy did not highlight any changes in the mucosa. An abdominal multidetector computed tomography (MDCT) scan demonstrated hypertrophy of the inferior mesenteric artery (IMA), with an arteriovenous fistula (AVF) and a dilated inferior mesenteric vein (IMV) (Fig. 1). The cirrhotic appearance of the liver, along with portal vein occlusion, were noted. Medical treatment of high blood pressure was begun. The patient refused the invasive treatments of IMA-IMV AVF embolization or abdominal surgery. No other episode of hematochezia occurred during hospitalization and the patient was discharged with a clinical, laboratory, and imaging follow-up program.

Figure 1.

Abdominal MDCT with coronal volume rendering reconstruction shows an IMA-IMV AVF composed of a hypertrophic IMA (red vessel) with an AVF (arrowhead) at its distal third (pelvic region) and a dilated IMV (blue vessel).

IMA-IMV AVFs are extremely rare. Clinical symptoms are due to shunting-related arterial flow and pressure changes. The definitive diagnosis of vascular pathology is made through imaging studies (MDCT or DSA). Symptomatic IMA-IMVV AVFs can be treated with percutaneous endovascular embolization of the feeding artery (if no bowel resection is needed) or surgery.