Familial Mediterranean fever-associated diseases in children.
MEditerranean FeVer (MEFV) gene encodes for the pyrin protein and a mutated pyrin is associated with a prolonged or augmented inflammation. Hence, various diseases were reported to be associated with familial Mediterranean fever (FMF) or carriers of MEFV mutations. However, systematic evaluation of all associated diseases in children with FMF has not been done previously. The aim of this study was to investigate the frequency and type of FMF-associated diseases in children. Files of FMF patients who had been seen in two reference hospitals in Ankara, in the last two years, were retrospectively evaluated. Patients with FMF and concomitant diseases were included to the study. Among 600 FMF patients, 77 were found to have a concomitant disease (12.8%). Thirty patients (5%) had vasculitis; 21 (3.5%) had juvenile idiopathic artritis (JIA); 7 (1.16%) had inflammatory bowel disease (IBD) and 19 had other diseases including 5 patients with isolated sacroiliitis. Overall, 13 (2.17%) patients had sacroiliitis in our cohort. The most frequent mutation was M694V/M694V (44%) and 81% of the patients had at least one M694V mutation. Majority of the patients (74%) developed associated diseases while they were not receiving colchicine therapy. Certain inflammatory diseases including vasculitis, chronic arthritis and IBD were more frequently detected in patients with FMF during childhood. M694V mutation is a susceptibility factor for associated diseases. In countries where FMF is prevalent, clinicians dealing with FMF and other inflammatory diseases should be aware of these associations.