title: Familial Mediterranean fever with a single MEFV mutation: comparison of rare and common mutations in a Turkish paediatric cohort.
abstract: OBJECTIVE
  Presence of common MEFV gene mutations strengthened the diagnosis of FMF in addition to the typical clinical characteristics of FMF. However, there are also rare mutations. P369S, A744S, R761H, K695R, F479L are the main rare mutations in Turkish population. We aimed to evaluate FMF patients with a single allele MEFV mutation and to compare patients with common and rare mutations.
  
  
  METHODS
  We retrospectively reviewed the medical records of FMF patients with a single allele mutation who were followed up between 2008 and 2013 in six centres. We compared the patients with rare and common mutations for disease severity score, frequent exacerbations ( >1 attack per month), long attack period (>3 day), symptoms, age at the onset of symptoms, gender, consanguinity, and family history.
  
  
  RESULTS
  Two hundred and seventeen patients (M/F=101/116) with the diagnosis of FMF and single mutation were included. Heterozygote mutations were defined as common (M694V, V726A, M68OI) and rare mutations (A744S, P369S, K695R, R761H, F479L). Sixty-seven patients (27 males, 40 females) had one single rare mutation and 150 (74 males, 76 females) had one single common mutation. No difference was found between the rare and common mutations with respect to the disease severity score. There was no significant difference between common and rare heterozygote form of mutations in terms of disease severity.
  
  
  CONCLUSIONS
  Patients with typical characteristics of FMF, with some rare mutations (A744S, P369S) should be treated in the same manner as patients with a common mutation.
authors.affiliation: Department of Paediatric Nephrology, School of Medicine, Gazi University, Ankara, Turkey. oguzs@gazi.edu.tr.
authors.forename: Oguz
authors.initials: O
authors.lastname: Soylemezoglu
authors.affiliation: Department of Paediatric Nephrology, School of Medicine, Gazi University, Ankara, Turkey.
authors.forename: Yasar
authors.initials: Y
authors.lastname: Kandur
authors.affiliation: Department of Paediatric Nephrology and Rheumatology, School of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Ali
authors.initials: A
authors.lastname: Duzova
authors.affiliation: Department of Paediatric Nephrology, School of Medicine, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Ozan
authors.initials: O
authors.lastname: Ozkaya
authors.affiliation: Department of Paediatric Rheumatology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey.
authors.forename: Ozgür
authors.initials: O
authors.lastname: Kasapcopur
authors.affiliation: Department of Paediatric Nephrology, School of Medicine, Baskent University, Ankara, Turkey.
authors.forename: Esra
authors.initials: E
authors.lastname: Baskin
authors.affiliation: Department of Paediatric Nephrology, School of Medicine, Gazi University, Ankara, Turkey.
authors.forename: Kibriya
authors.initials: K
authors.lastname: Fidan
authors.affiliation: Department of Paediatric Nephrology and Rheumatology, School of Medicine, Ankara University, Ankara, Turkey.
authors.forename: Fatos
authors.initials: F
authors.lastname: Yalcinkaya
mesh_terms: D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003598:Cytoskeletal Proteins / Q000235:genetics*; D010505:Familial Mediterranean Fever / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics* / Q000628:therapy; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006579:Heterozygote; D006801:Humans; D008297:Male; D008499:Medical Records; D009154:Mutation; D010641:Phenotype; D011379:Prognosis; D000071198:Pyrin; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014421:Turkey / Q000453:epidemiology
chemical_list: D003598:Cytoskeletal Proteins; C000604192:MEFV protein, human; D000071198:Pyrin