The Comparison of Pediatric Patients with Familial Mediterranean Fever Originated from Turkey and Crimea

OBJECTIVE: We aimed to evaluate the clinical and laboratory features and MEFV allele distribution in Crimean Tatar familial Mediterranean fever patients and to compare them with Turkish familial Mediterranean fever patients and healthy controls. MATERIALS AND METHODS: All newly diagnosed familial Mediterranean fever patients with Crimean Tatar nationality (n = 18) in Children’s Regional Hospital in Simferopol were enrolled in the study and were compared to 40 familial Mediterranean fever cases followed up at Hacettepe University, Ankara, Turkey. The distribution of MEFV alleles was assessed in the 127 unrelated healthy Crimean Tatar adults aged 20 years or more from different parts of the Crimea peninsula. RESULTS: Age and gender distribution, the frequency of colchicine resistance, and colchicine intolerance were similar between Turkish and Crimean Tatar children with familial Mediterranean fever. The duration of familial Mediterranean fever attack was shorter in Turkish patients than in Crimean Tatar (2.0 vs. 3.0 days, P < .001). Chest pain was more frequent in Turkish familial Mediterranean fever patients, whereas arthralgia, arthritis, and erysipeloid rash were more common in Crimean TatarT. MEFV allele distribution in Crimean Tatar was M694V-81%, M680I and V726A 9.5% both, and 68.6%, 14.3%, and 12.9% in Turkish, consequently. Homozygous carriers were 11%, compound-heterozygous was 6%, and heterozygous was 83%, compared to Turkish being 45%, 30%, and 25%, respectively. The allele distribution in healthy Crimean Tatar and Turkish was 10.2% and M694V was 7.1%, M680I was 1.6%, and V726A was 1.6%. CONCLUSION: The similar MEFV allele prevalence in both populations suggests the high prevalence of familial Mediterranean fever and the high number of undiagnosed patients in the Crimea peninsula. Younger age at onset, shorter duration of attacks, the prevalence of articular involvement, and erysipeloid rash were distinctive features of familial Mediterranean fever in Crimean Tatar.