Recurrent Infective Endocarditis in a Drug Addict: A Case Report

Abstract

Infective endocarditis is a disease with a high mortality rate; mortality increases with the number of new episodes. Patients with relapsing endocarditis have a higher mortality rate per year (20%) than patients with a single episode (9%); moreover, the episodes of infective endocarditis on the prosthetic valve have a worse prognosis, with a mortality rate of 45% for each episode. In relapsing endocarditis, the following are distinguished: the relapses, characterized by the same germ, less than six months after the previous episode, and the reinfections, which may be caused by a different germ, or by the same germ, more than six months after previous episode. A recent analysis of the risk factors of recurrent bacterial endocarditis showed that the use of intravenous drugs, hemodialysis, immunosuppression and previous episodes of infective endocarditis played a major role, especially if they occurred on the prosthetic valve and if caused by S. aureus. Recurrent infectious endocarditis occurs more frequently in young male patients with HIV seropositivity, who routinely use intravenous drugs. We have analyzed the clinical case of a 36-year-old immunocompetent man with a long history of parenteral drug abuse, who has presented 6 new episodes of relapsing infective endocarditis on mitral valve and 2 reinfections since 2013. Between 2013 and 2016, the patient underwent two mitral valve replacements with a biological prosthesis implant and a mitral valve replacement with a mechanical prosthesis implant and a tricuspid annuloplasty. The remaining episodes were treated with medical therapy only. Currently in the literature 6 episodes of relapsing infective endocarditis and 1 reinfection in a single patient is the highest number of reported events.