F-18 FDG Uptake Patterns and Disease Activity of Collagen Vascular Diseases-Associated Arthritis

Abstract

The purpose of the present study was to investigate F-18 FDG uptake patterns, and to see whether joint F-18 FDG uptake reflected disease activity in patients with collagen vascular diseases (CVD)-associated arthritis. A total of 72 patients with CVD-associated arthritis and 30 control subjects who underwent F-18 FDG PET or PET/CT were retrospectively investigated. PET images of 12 major joints, 7 minor joints, and extra-articular accumulation were assessed. We investigated F-18 FDG uptake patterns and the relationships between the degree of F-18 FDG uptake and distribution, clinical symptoms, and laboratory test results. Remitting seronegative symmetric synovitis with pitting edema syndrome, mixed connective tissue disease, rheumatoid arthritis, and systemic sclerosis tended to show strong and multiple joint F-18 FDG uptake. F-18 FDG uptake was found in bone marrow (86%) and/or spleen (57%) in 7 patients with adult-onset Still disease. The maximum standardized uptake value (SUVmax) correlated with the counts of erythrocyte sedimentation rate, matrix metalloproteinase-3, IgG, and IgA. Joint swelling had a positive association with SUVmax. Multiple logistic regression analyses revealed that factor associated with increased SUVmax of the joint was joint swelling (P = 0.005). The degree of joint F-18 FDG uptake may contribute to predict active inflammatory process of the joint. In addition, F-18 FDG uptake patterns may have a potential which helps differential diagnosis of CVD-associated arthritis.