White blood cell scintigraphy in the diagnosis of infection of endovascular prostheses within the first month after implantation.

Background: 99mTc-HMPAO-labeled leukocyte scintigraphy (WBCs) is useful in the diagnosis of vascular graft infection. However, false positives can occur in the early postoperative period. There are no data concerning the usefulness of WBCs in detecting endovascular prosthesis infection during this period. The aim of our study was to assess the reliability of WBCs in the diagnosis of early infection after endovascular prosthesis implantation. Material/Methods: 23 patients treated with endovascular grafts were submitted to preoperative diagnostic screening and to 3 WBCs (1 week before, 1 week after, and 1 month after surgery). After the last WBCs, all patients underwent a 14-month follow-up (range 6-37 months, median 12 months). Results: Three patients died, at 3, 4 and 5 months after surgery respectively. At the end of the follow-up, the presence of infection was demonstrated in one patient Of the 70 WBCs performed, 4 gave positive results. No positive scintigraphies were obtained in the preoperative period. A positive scintigraphy was found one week after surgery in a patient who showed lymphorrhage at the site of surgical access. In the same patient, the scintigraphic result returned to normal at 1-month scintigraphy. At 12-month follow-up the patient did not present signs of infection. Three positive scintigraphies were obtained in the same patient. In this patient clinical symptoms of graft infection became evident about 19 months after surgery. WBCs was repeated and showed extension of the infection. The infection was confirmed at surgery. Conclusions: WBCs do not provide false-positives in the first month after endovascular prosthesis implantation.