MEFV and familial Mediterranean fever: In 2007, Kaplan et al. proposed a set of diagnostic criteria for PFM, based on a series of 15 pediatric patients with FMF and PFM, among whom 5 (33%) patients developed PFM as the first manifestation of FMF, and 93% of them had the mutation M694V in the MEFV gene (80% in homozygosis) [44] (Table 1).