Recurrent Fulminant Myocarditis Accompanied by Lymphoid Follicle Formation in Myocardium

A 76-year-old man developed repeated fulminant myocarditis in a short period, and immunosuppressive therapy was remarkably effective. A pathologic evaluation showed that inflammatory cells had infiltrated the myocardium. Not only invasion of inflammatory cells but also the formation of lymphoid follicle was noted. Chronic myocardial inflammation was proven, but cardiac sarcoidosis was negative according to the results of various examinations. This is the first report of recurrent autoimmune myocarditis with a lymphoid follicle in the myocardium. These findings may suggest a novel pathogenesis of myocarditis.