Abstract
Familial Mediterranean fever (FMF) is a hereditary autoinflammatory disease characterized by recurrent and short duration (1-3 days) of fever, and serositis. Based on the nationwide survey of FMF in Japan, the estimated number of Japanese FMF patients is about three hundred. High grade fever was observed in 95.5%, chest pain in 35.8% abdominal pain in 62.7% and arthritis in 31.3% among Japanese FMF patients. AA amyloidosis was confirmed in 5 patients (3.7%). Colchicine was effective in 91.8% of Japanese FMF patients. A significant number of FMF patients exist in Japan, and early diagnosis and treatments should be required to prevent AA amyloidosis.