UPTAKE OF RADIOLABELED LEUKOCYTES IN PROSTHETIC GRAFT INFECTION

Abstract

The utility of radionuclide labeled leukocytes in the demonstration of infection within vascular prostheses was examined. The infrarental aorta was replaced with a 3 cm Dacron graft in 12 dogs. On the third postoperative day, 6 of the animals received an i.v. injection of 108 Staphylococcus aureus. Labeled leukocyte scans were performed at postoperative days 1 and 3, and then weekly for 8 wk within In-111 and Tc-99 labeled autologous leukocytes. When scans showed focal uptake of isotope in the area of the prosthetic material, the grafts were aseptically excised and cultured on mannitol-salt agar. Both control and infected aniamls had retroperitoneal isotope activity in the immediate postoperative period that disappeared by the end of the 1st wk. By the eighth postoperative wk, all of the animals that received the bactermic challenge had both radionuclide concentration in the region of the vascular prosthesis and S. aureus cultured subsequently from the perigraft tissues. None of the control animals had either radionuclide or bacteriologic evidence of infection at the eighth postoperative week. The radiolabeled leukocyte scan is evidently a highly sensitive and specific technique, clinically applicable for the diagnosis of vascular prosthetic infections.