Guidelines for UK practice for the management of MRSA infection prescribing in the community

1
EDUCATIONAL WORKSHOPS 2009
CASE PRESENTATION THREE
Hes got another one, doctor A difficult case
of recurrent MRSA bacteraemiaAuthor Nick
Brown, Addenbrookes Hospital
Acknowledgement Sani Aliyu, Sandwell and West
Birmingham Hospitals now Addenbrookes
Hospital Details of the original case report have
been adapted to emphasise particular points
2

• Sponsored through an unrestricted educational
  grant from Novartis Pharmaceutical Ltd to help
  support the cost of developing and hosting this
  educational workshop series

3
Background

• 65 y old male
• Past history of hypertension and cerebro-vascular
  disease
• July 2003
• Aortic aneurysm and complications
• Endovascular aortic aneurysm repair (EVAR)
• post-operative bleed requiring laparotomy
• paraparesis secondary to spinal cord ischaemia
• long term suprapubic catheter
• longstanding sacral pressure sores

Author Nick Brown, Addenbrookes Hospital
4
July 2007

• Admitted with fever four years after aneurysm
  repair
• Blood cultures MRSA (isolate 1)
• X-ray pelvis and transoesophageal echocardiogram
  (TOE) normal
• 2 weeks iv vancomycin plus oral rifampicin, then
  stopped
• Question
• What was the source of infection?
• How would you have treated it?

Author Nick Brown, Addenbrookes Hospital
5
July 2007

• 5 days later- pyrexia
• MRSA again in blood cultures (isolate 2)
• Re-started vancomycin plus rifampicin for 4 weeks
  
• Home on doxycycline plus rifampicin for a further
  4 weeks

Author Nick Brown, Addenbrookes Hospital
6
November 2007

• re-admitted with fever and back pain after 9 days
  at home
• Blood cultures MRSA (isolate 3)
• Transthoracic echocardiogram (TTE) normal
• Magnetic resonance imaging (MRI) spine - normal
• WCC scan suggestive of increased uptake in lower
  vertebra
• 1 week vancomycin, then MIC for MRSA strain
  reported as 3 mg/L
• intravenous linezolid for 10 days, then home on
  further 4 weeks oral

Author Nick Brown, Addenbrookes Hospital
7
Imaging 1 Indium-111 labelled white cell scan
showing localised area of increased uptake in the
lower abdomen or perhaps in the vertebrae
8
Population analysis of GISA
9
January 2008

• re-admitted in septic shock, day 38 linezolid
• MRSA in blood (isolate 4)
• intravenous daptomycin - five fold rise in CK,
  therefore stopped (was on a statin at the same
  time)
• blood cultures MRSA (isolate 5)
• Quinupristin/dalfopristin plus fusidic acid for
  12 weeks

Author Nick Brown, Addenbrookes Hospital
10
Late February 2008

• Blood cultures sterile by week 3 of
  quinupristin/dalfopristin plus fusidic acid
• inflammatory markers settling
• Computerised axial tomography (CT) scan at week 7
  increased thickness of aneurysm wall compared
  to previous scans

Author Nick Brown, Addenbrookes Hospital
11
Imaging 2 Computerised tomography (CT) scan
showing aortic graft in situ with thickening of
the aortic wall
12
April 2008

• Cardiothoracic review - no surgical intervention
  indicated
• 11 weeks into quinupristin/dalfopristin treatment
• septic again
• ESBL-producing E. coli in urine and femoral line
  tip
• meropenem for 10 days
• quinupristin/dalfopristin discontinued end of 12
  weeks
• blood cultures just before quinupristin/dalfoprist
  in stopped MRSA (isolate 6)

Author Nick Brown, Addenbrookes Hospital
13
April 2008

• Quinupristin/dalfopristin re-started (1 week
  later) plus daptomycin 4mg/kg
• CK levels remain normal
• 2 weeks - Quinupristin/dalfopristin switched to
  gentamicin and daptomycin dose increased to
  10mg/kg
• new femoral line

Author Nick Brown, Addenbrookes Hospital
14
Mid-July 2008

• Gentamicin stopped after 4 weeks
• MRSA bacteraemia persists (isolate 7)
• 8 weeks into daptomycin treatment - progressive
  rise in MIC
• daptomycin MIC 0.125 mg/L initially, but peaked
  at 12.0 mg/L
• Isolates now also resistant to rifampicin and
  fusidic acid
• Positron emission tomography (PET) scan confirms
  aortic graft infection

Author Nick Brown, Addenbrookes Hospital
15
Imaging 3 Positron emission tomography (PET)
scan showing increased tracer activity in
relation to the aortic graft
16
End-July 2008

• Aortic graft replaced
• Cultures of graft are negative, but S. aureus
  identified by 16s rDNA PCR
• Given iv linezolid, then oral fosfomycin,
  doxycycline plus chloamphenicol for 4 weeks
• End-August 2008
• switched to oral doxycycline alone
• 12 sets of blood cultures negative as at 1 Oct
  2008

Author Nick Brown, Addenbrookes Hospital