The present study was not only to review clinical and demographic features of Familial Mediterranean Fever patients but also to investigate whether there is a phenotype–genotype correlations in the same patient population. Medical records of 65 patients from Rheumatology clinic at specialized Cairo University Pediatric Hospital were retrospectively reviewed and classified into two groups according to mutations: homozygous and heterozygous groups. Our data indicate that presentation with severe phenotype in heterozygous patients should be further analyzed for less common second MEFV mutation using gene sequencing.