View source for Staphylococcus aureus bacteremia

== Classification ==

* '''Community-onset:''' positive blood culture obtained within 48 hours of presentation
* '''Nosocomial:''' positive blood culture obtained after 48 hours of presentation

== Etiology ==

* IVDU
* Poor dentition
* Dental work

== Clinical Manifestations ==

* Often non-specific fevers and chills, diagnosed on blood cultures
* May have back pain unrelated to spinal osteomyelitis
* May present with focus of metastatic disease

== Investigations ==

* Repeat blood cultures every 24 to 48 hours until negative
* Transthoracic echo (TTE) or transesophageal echo (TEE)
** A modern TTE that is good-quality and shows normal valves is quite good, though TEE is still better

== Management ==

* Infectious diseases consultation
* Must rule out endocarditis! TTE, followed by TEE if suspicion remains high
* Low risk for endocarditis (no TEE) if all of the following:
** No intracardiac device
** Sterile follow-up blood cultures within 4 days from the initial set
** No hemodialysis
** Nosocomial acquisition of [[S. aureus]]
** Absence of secondary foci
** No clinical signs of endocarditis
* Uncomplicated if
** Endocarditis is excluded
** No implanted prostheses
** Blood cultures clear by 2-4 days
** Defervesces within 72 hours
** No evidence of metastases
** +/- identified source has been removed
* Two-week course acceptable if uncomplicated, otherwise 4-6 weeks
* MSSA: [[cloxacillin]] 2g IV q4h for 2 weeks ([[cefazolin]] as an alternative)
* MRSA: [[vancomycin]] 1g IV q12h for 2 weeks
** Adjust based on serum trough before every fourth dose
** Target trough 15-20

== Prognosis ==

* Mortality 20-50% at 30 days, 60% at 1 year
* Mortality halved by ID consult
* Prognosis worse with
** Increased age
** Female sex
** Pneumonia or source unknown
** Dementia
** Increasing comorbidities
** Shock at time of presentation
** Institutionalized patient

== Further Reading ==

{{DISPLAYTITLE:''Staphylococcus aureus'' bacteremia}}
[[Category:Endovascular infections]]