DIAGNOSIS OF PROSTHETIC VASCULAR GRAFT INFECTION BY TECHNETIUM-99M-HMPAO-LABELED LEUKOCYTES

The purpose of this study was to determine the usefulness of Tc-99m-HM PAO-labeled leukocyte scans in the diagnosis of prosthetic vascular gr aft infection. Methods: We performed 75 scans in 61 patients with vasc ular grafts. Thirty-six patients were evaluated for suspected infectio n and 25 were control patients. Scintigraphic images were performed at 5 min, 30 min, 3 hr and, occasionally, 24 hr. Persistent increased up take at 3 hr along the suspected area of the graft was considered evid ence of graft infection. Results: All 20 infected grafts were detected with Tc-99-HMPAO leukocyte scan. The sensitivity and specificity of t he scan in the detection of infected graft were 100%. We also detected two pelvic abscesses, two infected fistulae, two soft-tissue infectio ns, three cases of ischemic colitis, one acute diverticulitis, one inf ected hematoma, one septic arthritis and one noninfected hematoma. One patient with a superficial groin infection had a negative scan. The e ight pseudoaneurysms did not show scintigraphic evidence of graft infe ction. Correlative CT studies were performed in 12 cases. Conclusion: Technetium-99m-HMPAO-labeled leukocyte scan is an accurate and valuabl e diagnostic method for evaluation of suspected prosthetic vascular gr aft infection.