Background Familial Mediterranean Fever (FMF) is an autoinflammatory disease with recurrent attacks of fever, serositis and arthritis. The most frequently complication of FMF is amyloidosis, which causes frequently mortality and morbidity. The pathogenesis of amyloidosis is unknown. In the other hand other chronic inflammatory disorders may cause secondary amyloidoses. Except SAA, it was not found a common genetic susceptibility for the secondary amyloidoses associated with different inflammatory disorders.
Objectives We aimed in this study to investigate the role of MEFV gene and TNFRSF1A gene in the pathogenesis of amyloidosis which is not associated with FMF or other hereditary periodic fever syndromes (HPFS).
Methods The study group is consisted of 47 FMF patients without amyloidosis, 42 FMF patients with amyloidosis, 37 patients with AA amyloidosis without FMF or other HPFS and 45 healthy controls. We analyzed the TNFRSF1A gene exon 2-5 and MEFV gene exon 10 mutations with sequencing in all patients.
Results We found increased frequency of rs116336305 SNP in TNFRSF1A gene in the FMF without amyloidosis group. An interesting finding was that this SNP was not found in amyloidosis group (p=0.003, OR:0.809, %95 CI:0, 708-0929). No other mutation was found in the TNFRSF1A gene.
The M694V mutation carrier rate is increased in the AA amyloidosis group without any FMF symptoms in comparison with healthy controls (p=0,042, OO:8,52, %95 CI: 0,98-74,3, %16,2 vs %2.2). There was no difference in the carrier rate of other MEFV mutations between these groups.
Conclusions This study reveals that rs116336305 mutation rate is increased in AAA and there is no amyloidosis in patients with this mutation. This data should be verified with larger patients groups. In the other hand we found increased M694V carrier rate in secondary amyloidosis group without FMF symptomes. These results suggest that M694V mutation should be investigated in the patients with proteinuria and without FMF symptomes, especially in those populations with high carrier MEFV mutation carrier rate.
Disclosure of Interest None Declared