Staphylococcus aureus: the enduring pathogen in surgery.

Staphylococcus aureus is part of the normal bacterial flora of the upper respiratory tract, especially the nose, but it can colonise other sites, such as the skin. However, S. aureus is also the commonest cause of surgical site infection (SSI) and is a major cause of bloodstream infection (BSI). The development of staphylococcal infection arises from a combination of bacterial factors, e.g. production of toxins and host factors, including underlying patient disease, e.g. diabetes mellitus. The surveillance of SSI and BSI are increasingly components of national quality programmes to reduce healthcare-associated infection (HCAI) in the UK, Ireland and beyond and the proportion of S. aureus BSI due to methicillin-resistant S. aureus (MRSA) has declined in recent years but not necessarily that due to methicillin-susceptible S. aureus. However, the complexity and sophistication of the staphylococcal genome has enabled it to change and adapt to varying circumstances such as exposure to a new antibiotic, adherence to a biomedical device and transfer from an animal to a human host. The future will perhaps see more cases of community-acquired MRSA and which may become endemic in hospitals and cause HCAI, technology becoming available to rapidly detect, type and characterise isolates for resistance and virulence and finally greater efforts at local and national level to drive down infection rates. However, good surgical practice, education and audit supported by new technology will enable surgeons to meet the challenges ahead.