Subtalar arthritis as a presenting symptom of Familial Mediterranean fever: case report and literature review.

Familial Mediterranean fever (FMF) is an autosomal, recessive disease affecting mainly people of Mediterranean origin. The primary pattern of FMF is acute, self-resolving periodic attacks of high-grade fever, accompanied by either peritonitis, pleuritis, or arthritis and sometimes typical ankle rash that simulates erysipelas. Rare manifestations, such as pericarditis or massive knee effusion, have been reported in the literature as a presenting symptom of FMF. The final diagnosis has recently become more accurate by identification of the gene for FMF. We describe a unique presenting symptom of subtalar arthritis with no former personal or family history of FMF. A genetic evaluation revealed a 694/726 genetic variant that confirmed the diagnosis of FMF. Treatment with daily colchicine, 1 mg/day, resulted in complete resolution of all complaints.