Staphylococcus aureus infective endocarditis: diagnosis and management guidelines

Abstract

S. aureus infective endocarditis (SAIE) is a serious infection associated with considerable morbidity and mortality. There is evidence that the incidence of SAIE is increasing. As its clinical features are non-specific, SAIE must be suspected in every case of S. aureus bacteraemia, whether it is associated with an obvious source or not. The optimal antimicrobial agent(s) and duration of treatment for SAIE are currently not known, but on the basis of present evidence, a minimum of 2 weeks of antimicrobial therapy is recommended for 'right-sided' SAIE, a minimum of 4 weeks for uncomplicated 'left-sided' SAIE, and a minimum of 6 weeks for complicated 'leftsided' or prosthetic valve SAIE. Although there is no evidence to suggest that combination therapy with a cell-wall active agent (e.g. flucloxacillin) and an aminoglycoside decreases mortality in SAIE, combination therapy should be considered during the initial 3-5 days of therapy as it can shorten the duration of bacteraemia. In complicated or prosthetic valve SAIE, early and close liaison with cardiology and cardiothoracic surgery services is essential. Rapid identification and susceptibility testing of the infecting organism are important in determining the choice of definitive antimicrobial therapy.

Reduced Vancomycin Susceptibility inStaphylococcus aureus, Including Vancomycin-Intermediate and Heterogeneous Vancomycin-Intermediate Strains: Resistance Mechanisms, Laboratory Detection, and Clinical Implications

“…Alexander Ogston first isolated Staphylococcus aureus from a surgical abscess in 1880 and described the role of S. aureus in localized infection and septicemia, including the use of animal models of infection (233,325). Staphylococcus aureus is recognized as a cause of a wide range of infections, from minor skin infections and chronic bone infections to devastating septicemia and endocarditis (44,45,48,63,99,124,179,207,218,277,(308)(309)(310)(311). The history of S. aureus is one of evolution and change.…”

Three Fatal Cases of Rapidly Progressive Infective Endocarditis Caused by Staphylococcus Aureus One Case With Huge Vegetation

“…3,4 Possible reasons for this increase include increased use of invasive procedures and intravascular devices, increased use of intravenous drug therapy, and improvements in diagnostic techniques. 1 Although there has been much development and improvement in both diagnostic and therapeutic methods, the mortality of S. aureus IE is still relatively high, ranging from 20% to 65%. 1,2,5,6 Nadji et al compared S. aureus IE with that caused by other pathogens, and found that the 36-month actual overall survival rate was significantly lower for S. aureus IE than IE caused by other pathogens.…”

“…Among cases of S. aureus IE, mortality is higher for MRSA than for MSSA, and for those with prosthetic valves than in cases involving native valves (range 25-59%). 1,7 It appears that early valve replacement surgery for prosthetic valve endocarditis lessens mortality, even in the absence of intracardiac or extracardiac complications. 8 However, that study may have been biased towards favorable outcomes in patients who underwent surgery, because patients in poor general condition may not have been selected for surgery.…”

“…2 In addition, the prevalence of S. aureus IE is also becoming higher in Japan, 3,4 concurrent with an increase in predisposing factors such as use of intravascular devices and intravenous drugs. 1 Here we report recent 3 cases of S. aureus IE that had a rapidly progressive fatal clinical course despite intensive antimicrobial therapy. One patient had a prosthetic mitral valve, which was infected with methicillin-sensitive S. aureus (MSSA), and the other 2 patients were infected with methicillin-resistant S. aureus (MRSA) on native valves.…”

“…1 Although diagnostic and therapeutic methods have improved and developed, the mortality rate for S. aureus IE is still higher than that caused by other pathogens. 2 In addition, the prevalence of S. aureus IE is also becoming higher in Japan, 3,4 concurrent with an increase in predisposing factors such as use of intravascular devices and intravenous drugs.…”