Your patient has a blood culture positive for Staphylococcus aureus - what do you do?

Staphylococcus  aureus bacteraemia  is  an  important  clinical  problem associated  with  a  high  mortality  rate  and  a  significant  burden  on  healthcare resources.   The  severity, rate  of  complications, and  prognosis  of  the  infection depend on a multitude of factors including underlying patient factors, the virulence of the strain of S. aureus, and the timeliness of appropriate antibiotic therapy. Detection  of  staphylococci  in  blood  culture  should  trigger  a  chain  of  events beginning with assessment of the patient to determine signs of sepsis and the likely significance of the organism isolated. The level of risk of your patient having MRSA must  be  assessed.   A  deep-seated  source, or  metastatic  complication, of  the bacteraemia must be suspected and sought, with the most important complication being  endocarditis.  This  assessment  should  not  delay  urgent  treatment  with  IV antibiotic therapy in a patient with signs of sepsis. Treatment should be guided by local  antibiotic  policy  alongside  advice  from  microbiology  and/or  infectious diseases consultants.

This overview takes the form of a clinical case scenario with a step-wise approach to  the  management  of  a  patient  from  first  isolation  of  staphylococci  in  a  blood culture to the management of MRSA endocarditis.