Clinical and genetic features of hereditary periodic fever syndromes in Hispanic patients: the Chilean experience.

Hereditary periodic fever syndromes (HPFS) are rare genetic diseases characterized by recurrent episodes of inflammation. Little information is available concerning HPFS in Latin American Hispanic population. The purpose of this study was to determine the clinical and genetic features of HPFS in Chilean population. A multicenter retrospective study of Hispanic Chilean patients with genetically confirmed HPFS was performed. We included 13 patients, 8 with familial Mediterranean fever (FMF) and 5 with TNF receptor-associated periodic syndrome (TRAPS), evaluated at rheumatology or pediatric rheumatology clinics between January 2007 and December 2010. Median age of symptoms onset was 8 years (range 1-35) and 8 years (range 0.3-21) for FMF and TRAPS, respectively. Median duration of fever was 3 days (range 2.5-15) for FMF and 21 days (range 9.5-30) for TRAPS. Genotyping of the MEFV gene in FMF patients revealed a homozygous M694V missense mutation in one patient, and heterozygous missense mutations in seven patients: M694V (n = 3), E148Q, R717H, A744S, and A511V. Sequencing of the TNFRSF1A gene in TRAPS patients revealed heterozygous missense mutations in four patients: T50M, C30R, R92Q, and IVS3+30:G→A, and a two-base pair deletion (IVS2-17_18del2bpCT) in one patient. Mutation in MEFV R717H and mutations in TNFRSF1A IVS2-17_18del2bpCT and IVS3+30:G→A are novel and have not been described previously. This study reports the largest series of genetically confirmed HPFS in Latin America, and adds evidence regarding the clinical and genetic characteristics of patients with FMF and TRAPS in Hispanic population. Mutations identified in MEFV and TNFRSF1A genes include defects reported in other ethnicities and novel mutations.