Evaluation of familial Mediterranean fever patients concomitant with juvenile spondyloarthropathy

Objectives: Familial Mediterranean fever (FMF) may present with various concominant diseases. This study aims to evaluate the clinical characteristics of patients with FMF with Juvenile Spondyloarthropathy (jSpA).

Method: Thirty-two patients diagnosed with FMF/jSpA, sixty four with FMF, and fifty-four with jSpA were included in this retrospective study. Three patient groups were compared in terms of clinical and laboratory features.

Results: The mean ages of patients in the FMF/jSpA, FMF and jSpA groups were 15,75(11,50-19,83), 15,41(6.83-21.50), and 16(9-22) years, respectively. Chronic arthritis (OR:0.11, p = 0.049), erythrocyte sedimentation rate values (OR:1.07, p = 0.011), and C- reactive protein values (OR:1,08, p:0,039) of the patients in remission period were found higher, the international severity scores for FMF (ISSF) before and after colchicine treatment (OR: 1,16, p: 0.021, OR: 2,21, p: 0,012) were higher in the FMF/jSpA group compared to FMF. Plantar fasciitis was more common and HLA-B27 positivity rate was lower in the FMF/jSpA group (OR:0.08, p = 0.024), (OR:4.71, p = 0.002) compared to jSpA. FMF/jSpA patients were divided as previous diagnosed FMF and jSpA.The diagnosis of jSpA was at a younger age(p = 0.002), Juvenile arthritis damage index-articular(p = 0.022) and extraarticular(p = 0,026), and the rate of biologic drug usage(p = 0.015) were higher in the previous jSpA group.The number of FMF attacks before colchicine was lower in the previous jSpA group(p = 0.02).

Conclusion: Our findings suggest that both classical FMF and jSpA findings were lower in patients with FMF/jSpA. Patients who were diagnosed with jSpA at an early age and who had enthesitis and plantar fasciitis should also be evaluated in terms of FMF.

Keywords: Children; familial Mediterranean fever (FMF); spondyloarthropathy.