Concomitant Diagnosis of Fibromyalgia and Ankylosing Spondylitis: Relation to Clinical Features and Plasma Pentraxin -3 Level.

Background: Ankylosing spondylitis (AS) is a chronic systemic inflammatory rheumatic disease that specifically affects the spine and sacroiliac joint. AS diagnosis is often delayed in the clinical practice and this delay may cause the patients to miss the chance of early treatment. Fibromyalgia (FM) is a frequently encountered clinical syndrome, fibromyalgianess is a term used when patients who are diagnosed with inflammatory arthropathies meet the criteria for FM syndrome as shown in rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Sjogren syndrome, and AS.