Detection of abdominal aortic graft infection: comparison of CT and in-labeled white blood cell scans.

Aortic graft infections are a rare but potentially lethal complication of aortic graft surgery. If the infection is limited to the groin, local therapy and preservation of the graft may be possible in some cases, whereas infections extending into the retroperitoneum require removal of the graft and revascularization of the lower limbs. The diagnosis and assessment of the extent of a graft infection is difficult on clinical grounds. A prospective study compared CT and indium-labeled white blood cell (In-WBC) scans in the diagnosis of aortic graft infection. Five patients with aortic graft infection and three patients without aortic graft infection were studied by both methods. CT correctly detected the retroperitoneal extension of the infection in three patients with groin infection; In-WBC scans diagnosed the extension only in one patient. Both CT and In-WBC were positive in two patients with aortic graft infection but no groin infection. Both studies were negative in the three patients without evidence of aortic graft infection. The study suggests that CT is more sensitive than In-WBC in evaluating the extent of aortic graft infection and should be the imaging method of choice.