Frequency of rheumatic diseases in patients with familial Mediterranean fever

Abstract

Purpose: Mutations in the Mediterranean FeVer (MEFV) gene, which causes familial Mediterranean fever(FMF), may also cause the emergence of other specific rheumatic diseases. This study aims to determine thefrequency of other rheumatologic diseases in paediatric FMF patients, evaluate whether there are clinical andgenetic differences between those with and without concomitant rheumatologic diseases, and compare the datawith previous studies.Materials and methods: The files of FMF patients who were followed up at the paediatric rheumatologydepartment were reviewed retrospectively. Demographic data, MEFV mutations, treatment, disease severityscores, and concomitant rheumatic diseases were recorded from the files.Results: There were 303 FMF patients (154 female/149 male). The mean age at diagnosis was 7.04±3.9 years.The mean disease duration was 5.33±3.13 years. In the cohort, 41 FMF patients (13.5%) were diagnosed withanother rheumatic disease. There were 22 cases of juvenile idiopathic arthritis (53.6%), seven cases of vasculitis(17%), six cases of periodic fever aphthous stomatitis and adenitis syndrome (14.6%), three cases of Behçet’sdisease (7.3%), two cases of acute rheumatic fever (4.8%), and one case of systemic lupus erythematosus(2.4%). Thirty-two of these of these 41 FMF patients (78%) had the M694V mutation (homozygous in 11,heterozygous in 21). Disease activity scores Pras and ISSF scores were higher in FMF patients with rheumaticdiseases (p=0.002 and p<0.001, respectively).Conclusion: Other rheumatologic diseases should be evaluated in FMF patients. Regarding other accompanyingrheumatic diseases, the M694V mutation and disease severity scores are notable factors.