The multi-face expression of familial Mediterranean fever in the child.

Familial Mediterranean fever (FMF) is characterized by recurrent self-limiting flares of fever in the absence of pathogens, autoantibodies or antigen specific T cells and is inherited as an autosomal recessive trait probably deriving from common ancestors of Armenian, Jew, Turk and Arab origin. The underlying pathogenetic mechanisms of FMF have not been fully interpreted, but mutations in the gene MEFV encoding pyrin, a natural repressor of proinflammatory molecules, result in uncontrolled relapsing systemic inflammation, increased leukocyte migration to serosal membranes or joints and inappropriate response to inflammatory stimuli. FMF heterogeneous phenotypic expression could originate both from allelic heterogeneity or from the existence of modulating genes. Proper diagnosis of FMF is needed to begin both specific clinical management and treatment based on continuous prophylactic administration of colchicine, preventing flares or at least the onset of amyloidosis.