Abstract
Typical familial Mediterranean fever（FMF）shows severe stomachache or chest/back pain accompanied
with fever． Some FMF patients show arthritis， however， the detail has been unclear． We here analyzed the
prolonged arthritis accompanied by FMF．25-year-old woman showed fever with stomachache，chest pain，
and arthritis in the knees and the fbot， which healed in a few days since her childhood． On the basis of MEFV
gene analysis revealing M6941/M6941 mutation， we made a diagnosed of FMF. After having colchicine， she
had had only mild attacks． She had pain and remarkable swelling in the right knee． Arthrocentesis revealed that
the synovial fluid was yellow and quite muddy，mainly including neutrophils． MRI fndings of the knee were
slight growth of synovial membrane，stagnation of synovial fluid，but no bone destruction．She had colchicine
continuously，thereafter，she had an arthritis with erysipelas like rash in the foot joint．The arthritis disappeared
after three months．We rarely see joint destruction in FMF．This may be attributed to the only activation
of neutrophils，in contrast to RA accompanied by articular destruction，in which T cell abnormalities were
recognized．
