An update on Staphylococcus aureus infective endocarditis from the International Society of Antimicrobial Chemotherapy (ISAC)

Staphylococcus aureus remains one of the dominant pathogens in infective endocarditis (IE) causing 25% to 30% of all cases [1], [2] including healthcare-associated IE which comprises about 30% of IE [3]. Most IE involve the aortic or mitral valves, with tricuspid valve involvement accounting for fewer than 10% of cases, often in association with injection drug use [1], [4], [5]. Prosthetic valve IE (PVE) and IE related to cardiovascular implantable electronic devices accounts for approximately one-third of all cases and is most commonly caused by coagulase-negative staphylococci [1], [5].

S. aureus is equipped with microbial surface components recognizing adhesive matrix molecules (MSCRAMMS), which are well defined adhesion molecules on the bacterial surface, able to promote adherence to cardiac endothelial cells. S. aureus can multiply and persist within cardiac cells, further promoting vegetation growth via activation of cytokines and thrombotic pathways [6]. Moreover in S. aureus -PVE, surface biofilm formation complicates eradication of the infection. S. aureus has been identified as an independent predictor of poor outcome in IE [7], [8]. In this review an expert group from the International Society of Antimicrobial Chemotherapy (ISAC) will present recent data, evidence and personal experience on S. aureus IE.