[Diagnosis and approach in suspected ankylosing spondylitis].

The time interval from first clinical symptoms to definite diagnosis of ankylosing spondylitis (Morbus Bechterew) is still too long. Thus, many years for essential therapeutic interventions are unequivocally lost. Therefore, it is most important to improve early diagnosis. To this aim the diagnostic criteria recently suggested by van der Linden are useful in relatively early stages of disease (table 1). Diagnosis is based on patient history, clinical examination and radiological signs of sacroiliitis. Blood examinations for ESR, rheumatoid factors and antinuclear antibodies are important with regard to differential diagnosis. The determination of the HLA-B27 haplotype as a diagnostic tool is irrelevant on terms of single cases, because at least 8% of ankylosing spondylitis patients are HLA-B27-negative and in middle europe at least 7% of normal controls exhibit this genetic marker.