The Biodistribution and Utility of 99mTc-Ethylenedicysteine-Deoxyglucose (99mTc-Glucosamine) in the Identification of Active Disease in Patients with Rheumatoid Arthritis—a Single Center Prospective Study

Abstract

PurposeOur objectives were to investigate the utility of 99mTc-ethylenedicysteine-deoxyglucose (ECDG) in identifying active disease in the joints of patients with rheumatoid arthritis (RA), as well as to evaluate the biodistribution of this radiopharmaceutical.MethodsA prospective study was conducted at the Department of Nuclear Medicine of the University of the Free State/Universitas Academic Hospital in Bloemfontein, South Africa. Twenty-two participants from the rheumatology department diagnosed with RA according to the ACR/EULAR classification criteria were enrolled. Participants were injected with 20–25 mCi of 99mTc-ECDG. Flow, blood pool, whole body, delayed static, and SPECT/CT images were acquired. Known sites of disease were qualitatively assessed for intensity of uptake, and disease severity was graded (Grade 0–3).ResultsTwenty-two participants were studied. The median (interquartile range) age was 59 (49–68) years, and the majority (n = 21; 95.5%) were females. There was abnormal increased uptake of 99mTc-ECDG noted in majority of the sites of known disease, including unknown sites. SPECT/CT imaging localized radiotracer uptake specifically to the synovial space. Similar biodistribution of radiotracer was noted in all patients, irrespective of disease severity or fasting status.Conclusion99mTc-ECDG can efficiently assess disease activity in the joints of patients with RA. It accumulates in sites of both clinical and subclinical disease and might be a very useful tool for the rheumatologist in the management of patients with RA.