A 28 year old man with 3 weeks of fever presented with tricuspid valve vegetation. What is the MOST common cause of Endocarditis in I.V. drug abusers?
Endocarditis among IV drug users especially that involving the tricuspid valve, is commonlycaused by Staph.aureus, many strains of which are methicillin resistant. Left-sided valve infection in addicts have more varied etiology. In addition to the usual causes of endocarditis, these cases are caused by pseudomonas aeruginosa and candida species and sporadically by unusual organisms such as Bacillus, Lactobacillus and corynebacterium species. Polymicrobial endocarditis occurs among IV drug users. Ref: Karchmer A.W. (2012). Chapter 124. Infective Endocarditis. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.
Staph.aureus
Candida albicans
Pseudomonas
Streptococcus viridans