Ankylosing spondylitis--the current situation and new therapeutic options

Ankylosing spondylitis (AS) is a chronic, immunologically mediated rheumatic disease whose progression largely depends on the extent of inflammatory activity. In contrast to rheumatoid arthritis (RA), therapeutic control of AS is very limited. Therapy of ankylosing spondylitis should not only control inflammatory processes, but also prevent structural damages and maintain the functions. Until recently, physiotherapy and non-steroidal antiphlogistics (NSA) therapy was a gold standard of AS treatment. NSA therapy alleviates inflammatory pain of spine in 60 to 80% of patients. According to the most recent findings, long-term administration of NSA can affect also X-ray progression. DMARD therapy, which is efficient in RA, has insignificant effect on axial form of AS. Sulfasalazine proved to be efficacious against peripheral form of AS; administration of MTX and leflunomide is not supported by controlled studies. Peripheral arthritis and enthesitis is usually treated by short-term application of corticoids. The fact remains that an important role in AS immunopathogenesis is played by TNF alpha whose increased levels were found in patients with AS in serum, synovial fluid and SI joints. Anti-TNF therapy with infliximab and etanercept proved to be highly efficacious in patients with AS resistant to conventional therapy. Infliximab and etanercept reduced the disease activity (50% improvement in more than half of patients), improved the function and slowed down the structural damage. MRI studies of anti-TNF therapy proved reduction of inflammatory activity in SI joints and spine. Other studies verified the efficacy of adalimumab in AS therapy and showed that adalimumab is a promising drug. Also, several randomized clinical studies proved efficacy of thalidomide whose administration, however, is limited by its severe adverse effects. Until now, the results of studies focused on pamidronate therapy appear to be rather controversial. Better understanding of AS pathogenesis led to implementation of new therapeutic procedures that significantly improve activity and functional condition of patients.