Background Familial Mediterranean Fever (FMF) is characterized by recurrent serositis and fever attacks, which may accompany such other rheumatic disorders as Henoch-Schonlein purpura (HSP), and Behcet's disease (BD). MEFV mutation modifies not only the clinical presentation of FMF but it also modifies other inflammatory disorders. However, the role of MEFV mutations in the FMF co-existing with other inflammatory disorders remains to be ascertained.

Objectives This study aims to investigate the frequency in which FMF coexists with other diseases, and determine whether MEFV mutations are involved in such simultaneity.

Methods Consecutive 142 patients with FMF investigated for MEFV mutation were enrolled for this study (F:87; M:55, mean age 32±12 yrs (11-62). They were diagnosed based on the Tell-Hashomer diagnostic criteria. The presence of MEFV mutation was investigated by multiplex-PCR reverse hybridization method in exon 2, 3, 5 and 10. All the patients were questioned for the presence of concomitant disorders and the medical records of these patients were revised retrospectively. A previous diagnosis for a disorder was considered true if it met the relevant criteria. MEFV mutations were divided into 2 groups including M694V and its subgroup (Group I) and others (Group II).

Results 129 of the 142 FMF patients had positive mutation for MEFV gene, but 13 of them showed no such mutation. M694V and its subgroup mutations (Group I) and other mutations (Group II) were found in 73 (56.6%) and 56 (43.4%) patients with FMF, respectively. Concomitant disorders were found in 16 FMF patients (21.9%) in Group I, 5 FMF (8.9%) patients in Group II (p=0.04). Concomitant disorders in Group I were as follows: 7 amyloidosis, 2 BD, 4 ankylosing spondylitis (AS), 1 antiphospholipid syndrome, 1 HSP, 1 combination of psoriatic arthritis, HSP and membranoproliferative glomerulonephritis. In group II, 1 amyloidosis, 1 BD, 1 AS, 1 ulcerative colitis, 1 vitiligo were found. No concurrent disorders could be found in FMF patients with negative MEFV mutation. The rate of the family history showed no significant difference for Groups I and II (63% vs 57%, p=0.5).

Conclusions MEFV mutations can modify both clinical manifestations of the FMF itself and those of other inflammatory disorders. The presence of M694V mutation may predispose FMF patients to developing other inflammatory disorders.

Disclosure of Interest : None declared

DOI 10.1136/annrheumdis-2014-eular.5550