Familial Mediterranean fever (FMF) is characterized by recurrent attacks of febrile serositis. While arthritis, pleuritis and peritonitis are common in FMF, no association of pericarditis with FMF has been described in detail. We retrospectively studied about 4000 FMF patients, using a computer chart review. Pericarditis was diagnosed when patients sustained attacks of pleuritic retrosternal chest pain and had typical findings in the electrocardiogram, echocardiogram or chest radiogram. The incidence and features of pericarditis in FMF were compared to published data. Over a period of 20 years, one or more episodes of pericarditis were recorded in 27 patients, a significantly higher incidence than in the general population (68 vs. 6 per 10(5) per year, p < 0.001). Each patient experienced 1-3 pericarditis attacks, lasting a mean of 4.2 days, accompanied by high temperature and symptoms of FMF attack at another site. The pericarditis attack resolved spontaneously and left no sequelae. FMF patients with pericarditis were comparable to other FMF patients in most demographic and clinical parameters. Pericarditis may be considered another rare manifestation of FMF.