Abstract
Staphylococcus aureus is an emergent etiology of community-acquired pneumonia (CAP) over the past 2 decades,
with severe community-acquired pneumonia (SCAP) caused by methicillin-resistant S. aureus (MRSA) leading to critical illness and death. S. aureus colonization is associated with a high incidence of pneumonia. Panton-Valentine leukocidin
(PVL) is one of the most important virulence factors of S. aureus associated with serious complications. In recent years, community-associated MRSA
(CA-MRSA) clones that caused infections in young adults and healthy individuals with
no exposure to health care settings and no classical risk factors have emerged. Clinical
features at admission including concurrent influenza infection, hemoptysis, multilobar
infiltrates, and neutropenia should suggest S. aureus CAP. Sputum Gram stains, cultures (or tracheobronchial aspirates or bronchoalveolar
lavage in mechanically ventilated patients), polymerase chain reaction (nasopharyngeal
or oropharyngeal or lower respiratory tract specimens), and two sets of blood cultures
should be obtained from patients presenting with severe S. aureus CAP. For CAP due to methicillin-susceptible S. aureus, first-line therapy is usually cefazolin, oxacillin, or ceftaroline. For CA-MRSA
pneumonia, linezolid is recommended. If vancomycin or teicoplanin are used, combination
with clindamycin or rifampicin should be considered in cases of PVL-positive MRSA
CAP.
Keywords
Staphylococcus aureus
- community-acquired pneumonia - methicillin-resistant
S. aureus
- Panton-Valentine leukocidin
