From Clinical Microbiology to Infection Pathogenesis: How Daring To Be Different Works for<i>Staphylococcus lugdunensis</i>

<jats:sec><jats:title>SUMMARY</jats:title><jats:p><jats:italic>Staphylococcus lugdunensis</jats:italic>has gained recognition as an atypically virulent pathogen with a unique microbiological and clinical profile.<jats:italic>S. lugdunensis</jats:italic>is coagulase negative due to the lack of production of secreted coagulase, but a membrane-bound form of the enzyme present in some isolates can result in misidentification of the organism as<jats:italic>Staphylococcus aureus</jats:italic>in the clinical microbiology laboratory.<jats:italic>S. lugdunensis</jats:italic>is a skin commensal and an infrequent pathogen compared to<jats:italic>S. aureus</jats:italic>and<jats:italic>S. epidermidis</jats:italic>, but clinically, infections caused by this organism resemble those caused by<jats:italic>S. aureus</jats:italic>rather than those caused by other coagulase-negative staphylococci.<jats:italic>S. lugdunensis</jats:italic>can cause acute and highly destructive cases of native valve endocarditis that often require surgical treatment in addition to antimicrobial therapy. Other types of<jats:italic>S. lugdunensis</jats:italic>infections include abscess and wound infection, urinary tract infection, and infection of intravascular catheters and other implanted medical devices.<jats:italic>S. lugdunensis</jats:italic>is generally susceptible to antimicrobial agents and shares CLSI antimicrobial susceptibility breakpoints with<jats:italic>S. aureus</jats:italic>. Virulence factors contributing to this organism's heightened pathogenicity remain largely unknown. Those characterized to date suggest that the organism has the ability to bind to and interact with host cells and to form biofilms on host tissues or prosthetic surfaces.</jats:p></jats:sec>