title: Monitoring in established RA: Role of imaging and soluble biomarkers.
abstract: Rheumatoid arthritis (RA) disease activity often remains difficult to define and to quantify. As a result, numerous techniques to estimate clinical activity have been developed and are in clinical use. Therefore, more objective biomarkers for early detection and accurate measurement and quantification of the disease burden are desired for clinical use and investigative studies. Several imaging and soluble biomarkers have been studied in the disease including conventional radiography, ultrasound, magnetic resonance imaging (MRI), and serum biomarker assays. While these tools are available to physicians in many settings, their role in routine clinical care remains unclear. The goals of this review are to outline the current state of the literature regarding each of these objective tools, assess their strengths and weaknesses, and clarify the knowledge gaps to be filled before these techniques may be more widely used.
authors.affiliation: Philadelphia Veterans׳ Affairs Medical Center, School of Medicine, Division of Rheumatology, University of Pennsylvania Perelman School of Medicine, and Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, PA, USA. Electronic address: bakerjo@uphs.upenn.edu.
authors.forename: Joshua F
authors.initials: JF
authors.lastname: Baker
authors.affiliation: Department of Rheumatology and Immunology, Singapore General Hospital, Singapore; Duke-NUS Graduate Medical School, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore. Electronic address: tan.york.kiat@singhealth.com.sg.
authors.forename: York Kiat
authors.initials: YK
authors.lastname: Tan
authors.affiliation: Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, UK; Leeds Musculoskeletal Biomedical Research Unit, Leeds, UK. Electronic address: p.conaghan@leeds.ac.uk.
authors.forename: Philip G
authors.initials: PG
authors.lastname: Conaghan
mesh_terms: D001172:Arthritis, Rheumatoid / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood*; D003952:Diagnostic Imaging / Q000379:methods*; D042241:Early Diagnosis; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D011859:Radiography; D014463:Ultrasonography
chemical_list: D015415:Biomarkers
keywords: Magnetic resonance imaging; Rheumatoid arthritis; Soluble biomarkers; Ultrasound