Relationship between the severity of enthesitis and clinical and laboratory parameters in patients with ankylosing spondylitis

In this study, we evaluated the relationship between the severity of enthesitis and outcome of measurement indices, clinical and laboratory parameters in patients with ankylosing spondylitis (AS). Thirty-three patients who fulfilled the modified New York criteria for AS were included in this study. Patients were asked to record the severity of current pain, night pain and morning stiffness on a 10-cm visual analogue scale. Stoke Enthesitis Index (SEI) was used to measure the severity of enthesitis. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI) and Bath Ankylosing Spondylitis Metrology Index (BASMI) were calculated. SEI was correlated positively only with BASDAI (r = 0.370, P = 0.034). There was no relation between SEI and laboratory parameters (Erythrocyte Sedimentation Rate and C Reactive Protein). Our data suggest that using an enthesitis index such as SEI can be a valuable tool in the evaluation of disease activity in patients with AS. However, evaluation of enthesitis severity is based on information given by patient and should be combined with objective parameters such as spinal measurements when assessing disease activity.