Evaluation of Disease-activity in Rheumatoid-arthritis and Other Arthritides Using (99m)technetium Labeled Nonspecific Human-immunoglobulin

Objective. To determine the usefulness of (99m)technetium (Tc-99m) immunoglobulin scintigraphy (Tc-99m IgG) in rheumatoid arthritis (RA) and in other arthritides. Methods. Scintigraphic scores were compared with the Ritchie index and biochemical variables of disease activity. Results. In RA, scintigraphic scores were reproducible and seemed to perform better than clinical scores. Moreover, the scores of synovial uptake correlated significantly with systemic variables of inflammation. Other inflammatory arthritides also disclosed uptake of Tc-99m IgG but noninflammatory joints did not. Conclusion. Although nonspecific for RA, Tc-99m IgG scintigraphy is a reliable tool to evaluate the degree and extent of joint inflammation.