Genetic and Clinical Study of Children with Familial Mediterranean Fever in Northeastern Iran

 Familial Mediterranean fever (FMF) is an autosomal recessive disorder caused by a mutation in the MEFV gene and characterized by recurrent episodes of fever and polyserositis.

 This study aimed to identify the frequency and distribution of MEFV mutations in children with FMF in northeastern Iran and determine clinical examinations.

 Our study was a descriptive and analytical cross-sectional study conducted among 29 patients under the age of 18 who visited the pediatric rheumatologist between April 2014 and 2021. After clinical diagnosis, the patients underwent genetic evaluation. The mutations related to each patient were identified using Sanger sequencing of the entire MEFV gene sequence. The rest of the information was extracted from the checklist. Finally, the data were analyzed using SPSS v. 16.

 Fever was the most common symptom, followed by abdominal pain. During the acute attack period, laboratory inflammatory factors increased in all patients. None of the patients had complications. There was no significant relationship between the demographic variables in the groups (benign, variant of uncertain significance [VUS], pathogen) except for the rate of hospitalization (P-value = 0.039). Moreover, 34.5% of the studied patients had pathogenic mutations. The most common mutation was E148Q, which was reported to be benign, followed by pathogenic mutations (M680I), with a frequency of 10.2%.

 The FMF is rare in Northeastern Iran, and the number of pathogenic mutations is lower compared to Northwest Iran and other studies. It is necessary to conduct a genetic examination and treatment of affected patients to control the course of the disease and its complications.