Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 33-04: Staphylococcal aureus Infections + Key Features Download Section PDF Listen +++ ++ An important cause of infections of intravascular and prosthetic devices and of wound infection after cardiothoracic surgery Less virulent than Staphylococcus aureus, and infections tend to be more indolent Normal flora of human skin + Clinical Findings Download Section PDF Listen +++ ++ Often associated with a foreign body Evidence of prosthetic valve infection Fever New murmur Instability of the prosthesis Signs of embolization + Diagnosis Download Section PDF Listen +++ ++ Infection (vs isolation as a contaminant) is more likely if Patient has a foreign body or an intravascular device in place Same strain is isolated from two or more blood cultures and from the foreign body site Contamination: more likely when a single blood culture is positive or if > 1 strain is isolated from blood cultures Antimicrobial susceptibility and speciation can help determine whether multiple strains have been isolated + Treatment Download Section PDF Listen +++ ++ Remove the foreign body or intravascular device when possible Sometimes treatment with antibiotics is preferable Surgical management may become necessary Vancomycin Dosage: 1 g every 12 hours intravenously Treatment of choice for patients with normal kidney function until susceptibility to penicillinase-resistant penicillins or other agents has been confirmed Duration of therapy is not established for infections caused by foreign devices, which may be eliminated by simply removing the device Treat bone or a prosthetic valve infection for 6 weeks Vancomycin plus rifampin, 300 mg twice daily orally, and gentamicin, 1 mg/kg every 8 hours intravenously, is recommended for prosthetic valve endocarditis caused by methicillin-resistant strains