Staphylococci Infections, Coagulase-Negative

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

Often associated with a foreign body

Evidence of prosthetic valve infection

• Fever

• New murmur

• Instability of the prosthesis

• Signs of embolization

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

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