Although elevated G-CSF in the serum from FMF patients had not been reported previously, Stojanov et al observed that the serum level of G-CSF was significantly higher in patients with periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) attacks.37 We also detected the elevated expression of CD64 on neutrophils in patients with FMF.38,39 These observations support the importance of G-CSF in FMF attack. This evidence concerns the gene FCGR1A and familial Mediterranean fever.