Bacteraemia

Question 1

A 74 year old man presents to the hospital because a blood culture taken by his GP 24 hours prior has grown a gram positive coccus, likely Staphylococcus, in 2/2 bottles. This patient has a mechanical aortic valve and is on warfarin. He has been unwell for a few days and saw his GP with fever, malaise and rigors. The GP diagnosed an URTI and prescribed Amoxycillin/clavulanic acid (Augmentin). How would you assess and manage him?

Imp/DDx/Goals

Answer 1

Impression
Likely a staph bateraemia given positive BC bottles and ?gram positive gram stain. This is a medical emergency given systemic features of presentation. Would be concerned about complications of staph bacteraemia including; toxic shock syndrome, end-organ damage, and endocarditis given aortic valve replacement.

Goals

• emergently treat patient to stabilise and maintain haemodynamic stability, as well as prevent life-threatening complications.
• complete a comprehensive patient assessment, establish ongoing management plan

Question 2

Staph- Bacteraemia - Assessment

Answer 2

Assessment
Would take an A to E approach given the severity of this presentation.
A - ensure patency, maintaining own. adjuncts as required
B - RR, Sats, monitoring - provide supplemental. assess for signs of infection given ?URTI
C - IV access, run bloods (VBG, FBC, UEC, etc), BP monitoring, take blood cultures, preferably two separate peripheral sites, 3rd one if suspicious of endocarditis
D - GCS
E - secondary survey (wounds, lines), general inspection (look toxic)
F - Fluids catheter, bolus, start empirical antibiotic treatment
G - BSL

Escalate care to on-call reg, arrange ID consult

Question 3

Staph Bacteraemia - History

Answer 3

History

• sx: malaise, lethargy, fever, rash, headache,urinary sx, respiratory sx. timeline of illness
• risk: IVDU, recent illness, immunocompromised
• Medical and surgical Hx
• medications (immunosuppressive, chemotherapeutic)
• SNAP

Question 4

Staph Bacteraemia - Examination

Answer 4

Examination
Would take an A to E approach initially as described
- General observations + vital signs
- cardiorespiratory examination - evidence of haemodynamic instability

Question 5

Staph Bacteraemia - Investigations

Answer 5

Investigations
Septic screen - idenitfy source of infection (CXR,
- Bedside: VBG, vitals monitoring
- Bloods: FBC, UEC, LFT,
- Imaging: CXR for septic screen. consider further investigation if suspecting endocarditis/ other complications of staph bacteraemia

Diagnostic for endocarditis

• Echocardiography - vegetations, valvular dysfunction
• positive blood cultures

Question 6

Staph Bacteraemia - Management

Answer 6

Management
Supportive
- stabilising measures: fluids, supplemental 02
- empirical abx (fluclox + vancomycin IV)
- Dispositioning: ICU for ongoing care, ID consult
- regular obs/ monitoring
- investigations for end-organ damage
- patient and family education

Definitive

• Specific antibiotic therapy once sensitivities are returned (MSSA = fluclox, MRSA = vanc). 6 weeks of therapy from negative culture - may require PICC line insertion
• valve replacement if endocarditis - cardio input