The aim of the present study was to investigate the prevalence of MEFV gene mutations in patients with ankylosing spondylitis (AS) and to assess the clinical significance of the MEFV gene mutations in AS.

Eighty AS patients and 85 healthy controls were examined for 12 common MEFV mutations via strip-assay technique. Bath ankylosing spondylitis disease activity index (BASDAI), bath ankylosing spondylitis functional index (BASFI), visual analogue scale (VAS) for pain, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), Schober test, chest expansion measurements, hip involvement, ocular involvement, articular pain, and presence of syndesmophytes were used to assess the disease severity in patients.

Twenty-four of the AS patients (30%) and 17 of the healthy controls (20%) were found to carry a single MEFV mutation. There was no significant difference between the AS patients and controls in terms of MEFV gene mutation frequency (p = 0.13, OR: 1.71, 95% CI: 0.83–3.50). When the patients were divided into two groups as MEFV mutation carriers and noncarriers, there was significant difference between the groups regarding BASFI and BASDAI whereas there was no significant difference in VAS score for pain. No association was found with the clinical findings and MEFV mutation except hip involvement. While there was no significant difference in CRP levels, individuals with MEFV mutation had a higher ESR than the noncarriers.

MEFV gene mutation carriage rate was not found to be significantly higher in AS patients when compared with healthy controls. However having an MEFV mutation seems to aggravate the disease course in AS.