SERONEGATIVE ARTHRITIS (MA KHAN, SECTION EDITOR) Current Concept of Spondyloarthritis: Special Emphasis on Early Referral and Diagnosis Salih Ozgocmen & Muhammad Asim Khan # Springer Science+Business Media, LLC 2012 Abstract Ankylosing spondylitis is the prototype of in- flammatory rheumatic diseases grouped under the term spondyloarthritis or spondyloarthropathy (SpA). New clas- sification criteria for SpA have now been proposed; the patients are subgrouped into (1) a predominantly axial dis- ease, termed axial SpA, which includes AS, and (2) periph- eral SpA. There is an unacceptable delay in the diagnosis of axial SpA, and there are still no validated diagnostic criteria for SpA. An early diagnosis has now become increasingly important because effective therapies in the form of TNF antagonists have become available that are even more effective if used in early stages of the disease. Therefore, new strategies are being proposed that will assist in mak- ing an early diagnosis and will also help primary care physicians in screening for these patients so that they can be referred to rheumatologists when the disease is still in its early stages. These strategies may be less efficient for early referral of children and adolescents suffering from SpA, because their most important early manifestation is not inflammatory back pain but peripheral arthritis and enthesitis. There is, therefore, a need to develop a different strategy for children and adolescents with SpA through the use, preferably, of the ASAS/EULAR classification criteria for peripheral SpA, more so than the classification criteria for axSpA. Keywords Spondyloarthritis . Spondyloarthropathy . Ankylosing spondylitis . Classification criteria . Axial spondyloarthritis . Peripheral spondyloarthritis . Juvenile spondyloarthritis . Early referral . Diagnosis . Screening . Referral tool Introduction Ankylosing spondylitis (AS) is the leading chronic inflamma- tory rheumatic disease of the axial skeleton [1], and is the prototype of a group of diseases grouped under the term spon- dyloarthritis or spondyloarthropathy (SpA) (see Fig. 1). The diagnosis of AS requires X-ray evidence of sacroilitis (defined as bilateral grade 2 or unilateral grade 3 or 4) according to the modified New York classification criteria for AS [3]. Deciding about the existence of sacroiliitis on plain radiographs is not always very easy, even for rheumatologists and radiologists [4]. The new definition of inflammatory back pain (IBP) and the detection of inflammation in the sacroiliac joints and the spine by magnetic resonance imaging (MRI) has helped in the early identification of axial SpA in the "nonradiographic stage" of the disease, years before anything becomes evident on X-ray [5, 6]. The presence of sacroiliac joint inflammation (sacroiliitis) on musculoskeletal imaging (X-ray or MRI) in the presence of clinical manifestations is virtually diagnostic. The name, AS, is more restrictive, since it requires X-ray evidence of sacroiliitis, and such a requirement is one of the reasons that the diagnosis is often delayed by 5–10 years [7, 8], and during this period of diagnostic uncertainty, many patients may undergo unnecessary or even invasive investigations and receive inappropriate treatment. The Concept of Axial SpA Axial SpA comprises a heterogeneous group of diseases that have many overlapping clinical feature; the important S. Ozgocmen Department of PMR, Division of Rheumatology, School of Medicine, Erciyes University, Gevher Nesibe Hospital, 38039 Kayseri, Turkey e-mail: sozgocmen@erciyes.edu.tr M. A. Khan (*) MetroHealth Medical Center, Division of Rheumatology, Case Western Reserve University School of Medicine, 2500 MetroHealth Drive, Cleveland, OH 44109-1998, USA e-mail: mkhan@metrohealth.org Curr Rheumatol Rep DOI 10.1007/s11926-012-0274-2