Familial Mediterranean Fever with Rheumatoid Arthritis Complicated by Pulmonary Paragonimiasis.

A 42-year-old woman presented with an intermittent fever and chest and back pain, and an abnormal chest shadow was detected. She was diagnosed with paragonimiasis caused by Paragonimus westermani. Praziquantel therapy improved the abnormal chest shadow, but did not relieve her symptoms. She was also diagnosed with familial Mediterranean fever (FMF), and colchicine therapy resolved her symptoms. She subsequently developed arthralgia and morning stiffness in her hands. We also diagnosed the patient with rheumatoid arthritis (RA), and corticosteroid and salazosulfapyridine therapy improved her symptoms. The existence of paragonimiasis complicated the diagnosis of FMF. The coexistence of FMF and RA is very rare, but does exist.