A 17 year old girl was admitted to our rheumatology clinic with right knee pain and swelling for the past 3 months. A diagnosis of familial Mediterranean fever (FMF) had been made 8 years previously; she had recurrent attacks of fever, abdominal pain, and knee arthritis. She had been using colchicine 1.5 mg/day regularly since then. Although her abdominal attacks and fever had subsided with colchicine treatment, recurrent mild knee attacks occurred almost every month. Two years ago she was found to have the homozygous M694V gene mutation for FMF. Three months ago, she was admitted to hospital owing to monarthritis in her right knee—but …