Comparison of Indium-111-labeled leukocyte scintigraphy and Technetium-99m joint scintigraphy in rheumatoid arthritis and osteoarthritis

This study was undertaken to evaluate the use of Indium-111-labeled leukocyte (111In-WBC) imaging compared with Technetium-99m pertechnetate (99mTcO4-) imaging in 19 patients with rheumatoid arthritis (RA) and 8 with osteoarthritis. Knee and wrist joints were evaluated for both radionuclides. The results indicated a good correlation of the clinical assessment of pain and swelling with joint uptake ratio (JUR) between 111In-WBC and 99mTcO4- in RA and osteoarthritis patients. We observed a discrepancy in both imagings in "burned out" cases. It was concluded that a JUR of 111In-WBC could distinguish active RA from inactive RA or osteoarthritis at a value of 1.15 and that the use of 111In-WBC was a more reliable procedure than 99mTcO4-.