Interleukin-1β in plasma and synovial fluid in relation to radiographic changes in arthritic temporomandibular joints

The aim of this study was to investigate the level of the cytokine IL-IB in plasma and temporomandibular joint (TMJ) synovial fluid of patients with arthropathies, and to study the relation between IL-1 beta levels of synovial fluid and plasma as well as radiographic changes of the TMJ. 31 patients with general disease, 14 with rheumatoid arthritis (RA) and 17 with various arthritides were included in the study. Synovial fluid and blood samples were collected, and an individualized tomography of the TMJ was performed. Detectable levels of IL-1 beta were found in 5 out of 39 synovial fluids and in 10 out of 27 plasma samples. The presence of IL-1 beta in both plasma and synovial fluid was more frequent in RA patients than in the non-RA group. The extension of radiographic erosion was significantly greater in joints with IL-1 beta than in those without. Both the extension of erosion and grade of radiographic changes of the TMJ were greater in patients with detectable IL-1 beta level of plasma than in patients without. Our study indicates that presence of IL-1 beta in plasma and synovial fluid is related to radiographic changes of the TMT.