Detection of Subacute Infectious Foci with Indium-111-Labeled Autologous Leukocytes and Indium-111-Labeled Human Nonspecific Immunoglobulin G: A Prospective Comparative Study

In 35 patients suspected of an infectious focus, the outcome of scintigraphy with 111In-labeled autologous leukocytes (WBC) and 111In-labeled human nonspecific immunoglobulin G (IgG) was evaluated in a prospective comparative study. Clinical, roentgenologic and microbiologic findings were considered to be proof of the presence of infection or inflammation. In this group of patients with mainly subacute infections, 111In-IgG scintigraphy performed significantly better than 111In-WBC scintigraphy, especially in infections of the locomotor system, but also in various soft-tissue infections. Both techniques showed disappointing results in patients with disseminated yersinia infection and in some patients with tuberculosis. Overall sensitivity and specificity was 74% and 100% for 111In-IgG scintigraphy and 52% and 78% for 111In-WBC scintigraphy, respectively.