THE EFFICACY OF INDIUM-111-POLYCLONAL IGG FOR THE DETECTION OF INFECTION AND INFLAMMATION

The purpose of this study was to determine the efficacy of In-111-poly clonal immunoglobulin (IgG) for the diagnosis of infection or inflamma tion. Methods: Fifty-three patients with suspected infection were pros pectively studied. Each underwent an In-111-polyclonal IgG study; biop sy, surgery, additional nuclear medicine scans and radiographic studie s were used to confirm the IgG scan results. Results: The polyclonal I gG scan had a sensitivity of 97.9% and a specificity of 94% for infect ion or inflammation. When only infection or severe inflammation such a s bowel infarction was considered, the sensitivity remained the same b ut the specificity fell to 83%. Chronic infections were detected equal ly as well as acute infections. Antibiotics, steroids, anti-inflammato ry agents, diabetes and diminished renal function did not affect scan sensitivity. There were no adverse reactions to the radiopharmaceutica l. Three patients underwent extended imaging. Their scans stayed posit ive for an average of 8 days. Three patients treated for infection had their scans turn negative on repeat study, confirming the efficacy of their antibiotic therapy. Conclusion: Indium-111-polyclonal IgG is an effective imaging agent of infection and/or inflammation that is usef ul in a variety of infections and in severe inflammatory diseases. The ease of preparation and safety make it an attractive alternative to l abeled leukocytes.