The prognostic value of 99m Tc-glucosamine imaging in patients with rheumatoid arthritis: a single center prospective study.

Abstract

Poor prognostic factors in rheumatoid arthritis (RA) are associated with a more severe form of the disease. Nuclear medicine functional imaging has shown remarkable merit at identifying active disease in patients with RA and is increasingly being used in this regard. However, its prognostic value has not been evaluated thoroughly. We aimed to assess the prognostic value of technetium-99m ( 99m Tc-) glucosamine imaging in patients with RA. Twenty-two participants diagnosed by an experienced rheumatologist with RA were recruited for inclusion in the study. Blood samples were obtained from each participant for baseline C-reactive protein, erythrocyte sedimentation rate, rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibody titer. On the same day, each participant was injected with 20-25 millicurie (mCi) of 99m Tc-glucosamine. Planar and single-photon emission computed tomography images of known disease sites were acquired up to 2 hours after radiopharmaceutical administration. Affected joints were qualitatively assessed and graded for 99m Tc-glucosamine uptake and compared with blood results. All participants affected joints had an increased uptake of the radiopharmaceutical, with 14 (63.6%) having elevated RF and anti-CCP antibody titers. Eight of the 14 patients with increased RF and anti-CCP antibodies had grade 3 uptake of 99m Tc-glucosamine. The remaining 6 had grade 2 uptake. A significant correlation between higher grade uptake and increased levels of RF and anti-CCP antibodies ( P = 0.031) was observed. We found a strong correlation between high-grade disease on imaging and the presence of RF and anti-CCP antibodies in patients with RA.