Clinical phenotypes and genetic analyses for diagnosis of systemic autoinflammatory diseases in adult patients with unexplained fever.

To make an accurate diagnosis of systemic autoinflammatory diseases (SAIDs), clinical and genetic analyses were performed in patients with unexplained fever. The clinical phenotype and genomic variants of 11 genes responsible for SAIDs were analyzed in 179 Japanese patients with unexplained fever. Genetic analysis was performed by next generation sequencing (NGS) on exons including exon-intron boundaries. Three cases met the diagnostic criteria for SAIDs other than familial Mediterranean fever (FMF). Considering 176 patients with unexplained fever, 43 cases (24.0%) were clinically diagnosed as FMF. Gene variants were found in 53 cases (30.1%) when searching for variants in the 10 disease genes other than the Twenty four percent of Japanese patients with unexplained fever were clinically diagnosed as FMF in this study. Low frequency but not pathogenic variants in genes other than