Investigation of the relationship between disease severity and development of amyloidosis and genetic mutation in FMF disease.

BACKGROUND: Familial Mediterranean fever (FMF) is an autosomal recessive genetic disease. Amyloidosis is the most important complication of FMF that determines the prognosis of the disease. AIMS: In our study, we have investigated the relationship between the genetic mutations with the disease severity and the frequency of development of amyloidosis inpatients with FMF. METHODS: A total of 148 patients with FMF were included this study. The relationship between disease activity score, clinical findings, response to treatment, and presence of amyloid and genetic mutations were evaluated. RESULTS: One hundred forty-eight patients (80 women (54%), 68 men (46%)) were enrolled over 18 years of age. The mean age of the patients was 30.98 ± 11.18 (18-67) years. In our study, the most frequently seen mutations are M694V, M680I, R202Q, and E148Q, respectively. The most common genotype is M694V/M694V mutation and this mutation has been found in 37 patients (25%). In 25 patients, M694V heterozygous have been found (16.8%). The third frequent mutationis M694V/M680I/R202Q has been found in13 patients (8.7%). In 23 patients, amyloidosis has been developed. Ten patients with amyloidosis have M694V homozygous mutations (27%) and 5 patients with amyloidosis M694V heterozygous (20%) mutations. The both of the two patients who carry the homozygous E148Q mutations have developed amyloidosis. CONCLUSIONS: In our study, the distribution of the frequency of mutations is consistent with other similar studies performed in Turkey. We found that patients with M694V mutation had a significantly higher rate of exacerbation, higher drug doses for treatment, and a close relationship with amyloidosis, as compared to patients with other mutations.