Clinical study of 7 cases of familial Mediterranean fever with MEFV gene mutation.

OBJECTIVE: Familial Mediterranean fever (FMF) had been considered a rare disease in Japan, but since the identification of the causative gene (MEFV) for pyrin/marenostrin in 1997, the occurrence of FMF has been successively reported. We reviewed the clinical features of 7 patients diagnosed with FMF by gene analysis.

METHODS: During April 2003 and March 2005, we investigated the clinical symptoms, treatment and MEFV types of 7 FMF patients who consulted the General Outpatient Clinic of Chiba University Hospital.

RESULTS: Six patients were in their 20-30s, and one was 54 years of age. There were 4 males and 3 females including a mother and child, and an adult male and his female cousin. Three were solitary incidences. In addition to intermittent fever, 4 patients had chest pain, 1 had abdominal pain, and 1 had chest or abdominal pain. The frequency of attacks was once per 3 months to 1 year in the early stage of the disease, but it slowly increased with disease progression. Leukocytosis and C-reactive protein (CRP) elevation were noted during attacks in all patients. On investigation of MEFV, heterozygosity for the compound pyrin L110P-E148Q/M694I, E148Q/M694I, L110P/E148Q and heterozygosity for pyrin variant M694I alone were detected. Daily administration of colchicine at 0.5 mg prevented attacks in 6 patients, however 1 patient required 1.0 mg for adequate prevention.

CONCLUSIONS: Although the incidence is rare, internists should be aware of the characteristic symptoms of FMF: periodic fever and serositis symptoms, and its presence in Japan despite the disease name.