Axial Spondyloarthritis: Evolving concepts regarding the disease's diagnosis and treatment

Spondyloarthritis (SpA) is a chronic inflammatory disease that affects the axial skeleton (axSpA) and/or the peripheral joints (p-SpA) and entheses. The natural history of SpA in the decades of the 80 and 90 s involved a progressive disease with pain, spinal stiffness, ankylosis of the axial skeleton, structural damage of peripheral joints, and a poor prognosis. In the last 20 years, enormous advances in understanding and managing SpA have occurred. With the introduction of the ASAS classification criteria and MRI, early disease recognition is now possible. The ASAS criteria widened the spectrum of SpA to include all the disease phenotypes, such as radiographic (r-axSpA), non-radiographic (nr-axSpA), and p-SpA and extraskeletal manifestations. Nowadays, the treatment of SpA is based on a shared decision between patients and rheumatologists and includes non-pharmacological and pharmacological therapies. Moreover, the discovery of TNFα, IL-17, which play a pivotal role in disease pathophysiology, has revolutionized disease management. Thus, new targeted therapies and many biological agents are now available and used in SpA patients. TNFα inhibitors (TNFi), IL-17, and JAK inhibitors were proven to be efficacious, with an acceptable toxicity profile. Overall, their efficacy and safety are comparable with some differences. Sustained clinical disease remission, low disease activity, improvement of patient's quality of life, and prevention of progression of structural damage, are the results of the above interventions. The concept of SpA has changed in the last 20 years. The disease burden can be ameliorated by early and accurate diagnosis and targeting therapies.