Staphylococcus aureus bacteraemia (SAB) quality of care indicators

To support best practice in the management of SABs, the Scottish Antimicrobial Prescribing Group (SAPG) have developed quality of care indicators.


1. Clinical Assessment

  • Assess for severity and sepsis if national early warning score (NEWS) is 5 or more and seek immediate assessment by senior clinician
  • Consider source: skin or soft tissue, surgical site, vascular device, indwelling device or prosthesis, bone or joint, spine, endocarditis, pacemaker or endovascular infection or injection drug use related infected deep vein thrombosis (DVT) are most common
  • Collect relevant microbiology samples, eg 2 further blood cultures (BCs) sets if endocarditis suspected, urine, pus, sputum, prosthetic material
  • Document SAB source and clinical management plan in patient records


2.  Source Control

  • Initiate discussion on source control within 24 hours of laboratory confirmation of SAB or identification of infection source
  • Remove any suspected non-permanent IV catheters immediately
  • Document IV catheter removal or reason for non-removal

Involve surgical specialist
To drain collections, abscesses, wash out joints and remove joint prosthesis or cardiovascular implantable device as soon as feasible

If source unknown – document details of full clinical examination conducted, and planned investigations, including specialist (surgical) review or imaging


3.  Echocardiography

Perform transthoracic echocardiogram (TTE) in all patients with SAB

  • Refer to cardiology if TTE suggestive of endocarditis

Transoesophageal echocardiogram (TOE)
(In patients where TOE is performed first-line a TTE is not needed.)

  • TOE is significantly more sensitive (90-100%) in detecting vegetations than TTE (50-60%)
  • Refer for TOE if patient has negative or equivocal TTE with predisposing cardiac conditions, prosthetic valve or pacemaker or complicated bacteraemia

 Optimal time to perform TTE or TOE:

  • If patients has predisposing cardiac conditions for endocarditis or risk factors for complicated bacteraemia then perform TTE/TOE within 3–5 days of first positive blood culture and no more than 14 days later


4.  Repeat blood cultures

  • Repeat blood cultures 48 hours after starting IV antibiotics and at 48 hour intervals until negative culture obtained
  • End collection of repeat blood cultures when first negative blood culture is obtained
  • Urgently reassess if persistently positive or if clinical deterioration
  • Persistent bacteraemia is associated with metastatic infection and increased risk of mortality


5.  Infection specialist consultation

Discuss all patients with SAB with an infection specialist (ID physician or microbiologist) who will:

  • Advise on those with endocarditis, complex, deep seated, device-related or persistent SABs, people who inject drugs (PWID) with associated infections, or where source is unknown
  • Confirm therapy recommendations and duration
  • Advise on suitability or appropriateness of outpatient parenteral antimicrobial therapy (OPAT) or future intravenous to oral switch therapy (IVOST) options
  • Consider antibiotic-related adverse events or failure to respond to treatment
  • Advise on healthcare associated SAB


6.  Intravenous (IV) antibiotic therapy

Flucloxacillin sensitive (MSSA- Methicillin sensitive Staphylococcus aureus) and no penicillin allergy

  • IV flucloxacillin 2g 4-6 hourly (max 8g daily)
  • Consider dose reduction only if creatinine clearance less than 10mls/min. Reduce to 1g 6 hourly if significant renal impairment

Flucloxacillin sensitive (MSSA) endocarditis:

  Patient Weight   Dose
  under 85kg   8g daily in 4 divided doses
  85kg and over   12g daily in 6 divided doses

MSSA and true penicillin allergy
– use vancomycin as per local guidelines and review when microbiology results are available

MRSA (Methicillin-resistant staphylococcus aureus) - if known MRSA carrier or previous MRSA infection

  • Use IV vancomycin (or as per previous microbiology sensitivities)
  • Consider adding IV flucloxacillin (if no penicillin allergy) pending sensitivity results
  • Review when microbiology results are available

Vancomycin alternative may be recommended by infection specialists based on laboratory or clinical factors

MRSA accounts for less than 4% of SAB infections in Scotland


7.  Duration of antibiotic therapy

Duration of therapy depends on whether bacteraemia is complicated or uncomplicated

  • Uncomplicated bacteraemia
    Definition: clearance of bacteraemia within 4 days for patients with repeat blood cultures, and no fever within 72 hours after the initiation of effective therapy. No implanted prostheses, endocarditis or other metastatic sites of infection.

Continue IV antimicrobial therapy for 14 days after clearance of bacteraemia

  • Complicated bacteraemia
    Definition: not meeting the criteria for uncomplicated bacteraemia  

Duration is dependent on source control and site/extent of infections but usually a minimum of 28 days with at least 14 days of IV therapy


8.  IV to oral switch therapy (IVOST)

  • Consider after 2 weeks IV therapy if deep seated/complex (non-endocarditis) infection if clinical improvement. Oral options, treatment duration, monitoring and follow up should be agreed with an infection specialist


9.  Outpatient parenteral antimicrobial therapy (OPAT) referral

  • Appropriateness and assessment of OPAT suitability requires evaluation by an OPAT infection specialist and OPAT specialist nurse and only if suitable local service is established
  • Consider OPAT referral to complete treatment of SAB if: clinically improving, repeat BCs at 48 hours are negative and no other indication for hospital admission. aureus endocarditis requires 14 days of inpatient treatment but may be considered later for OPAT if clinically improving and not requiring surgical intervention. PWIDs and others at risk of not completing inpatient treatment should be assessed carefully, including by addiction services, prior to discharge


10.  Medical discharge summary

  • Document SAB investigations and treatment plan in the medical discharge summary


This has also been developed in an algorithm format : SABs algorithm
Click on the link to download a copy of the : SABs quality indicators 

(accessible versions available on request)

Further reading

Content updated Feb 2023           Review Date : Feb 2026