Evaluation of Genotypic and Phenotypic Characteristics of Children with Familial Mediterranean Fever in Eastern Turkey

Objective: Familial Mediterranean fever (FMF) is a hereditary disease. It usually affects countries in the Mediterranean region and is common in Turks. This retrospective study was conducted to evaluate phenotype-genotype characteristics of children with FMF in Malatya district and surrounding areas in eastern Turkey.

Materials and methods: A total of 427 patients who had been diagnosed with clinical FMF between 2006 and 2015 were included in the study.

Results: Of the patients, 207 (48.5%) were female, and 220 (51.5%) were male. The mean age of diagnosis was 7.7±3.7 years, and the age of onset of complaints was 5.7±3.5 years. The delay of diagnosis was 1.9±1.8 years. The most common complaint was abdominal pain (95.1%). The most commonly detected mutant allele was M694V (26.9%) mutation. We detected heterozygous mutations in 203 (52%) patients, homozygous mutations in 71 (18%) patients, compound heterozygous mutations in 81 (22%) patients, and no mutation in 8% of the patients. The most common homozygous mutation was M694V (57.7%), the most common heterozygous mutation was E148Q (38.4%), and the most common compound heterozygous mutation was M694V/M680I (17.1%).

Conclusion: In our study, we found that the frequency of mutations was similar to that of the whole population of Turkey, and the severity of the disease was lower.