Coagulase-negative staphylococci (CoNS) are a major constituent of human skin flora. These organisms have become increasingly recognized as agents of nosocomial bloodstream infections. Patients at risk include those with prosthetic devices and immunocompromised hosts.
Most CoNS bloodstream infections are the result of infection related to intravascular catheters. Clinical manifestations include fever, hypotension, and leukocytosis.
CoNS are emerging as an important cause of native valve endocarditis in both community and healthcare settings. In addition, CoNS are the most frequent cause of prosthetic valve endocarditis within the first year after surgery.
CoNS (predominantly Staphylococcus epidermidis) accounts for at least 25 percent of cardiac device infections and may occur via inoculation at the time of device placement or by hematogenous seeding from another site.
CoNS are a common cause of vascular graft infection. In early-onset infections, local signs of infection are often present, while late-onset infections may be clinically occult and difficult to diagnose.
CoNS are a common cause of infection of prosthetic orthopedic devices. The organisms are frequently inoculated at the time of the arthroplasty, and infection may present indolently.
Surgical site infections due to CoNS are second only to S. aureus as an etiologic agent. CoNS are more often cultured from superficial incisional wounds than deeper wounds and are more likely to cause infections in "clean" procedures.
Neonates are a particularly high-risk group for infection due to CoNS. In addition to infection related to vascular catheters, neonates may also develop wound abscesses, pneumonia, urinary tract infections, meningitis, enterocolitis, and omphalitis caused by CoNS.