Staph Aureus Bacteraemia Flashcards
Describe staphylococci
Gram positive cocci
Form grape-like clusters on gram stain
Classification of Staph aureus infection
Healthcare associated
Community acquired
Also by the absence or presence of associated sites of infection
Describe the spectrum of staph aureus infections
Skin and soft tissue infection S.Aureus most commonly identified agent
Localised pyogenic staph infections
Deep seated abscesses, necrotising fasciitis, pyomyositis
Osteomyelitis, septic arthritis, discitis
infective endocarditis
Pneumonia, empyema
Frequent sites of distant septic metastases in S.Aureus infection
- Bones and joints
- epidural space and intervertebral discs
- native and prosthetic cardiac valves, cardiac devices
- visceral abscesses in spleen, kidneys, lungs
Investigations in bacteraemia
- Microscopy and culture
- multiple bood cultures before commencing antibiotic therapy
- repeat blood cultures 48-72hrs after commencing antimicrobial therapy
- biopsy samples
- xray, CT, MRI, radionuclide imaging
- transthoracic echocardiography, TOE
Management of invasive staph infections
- Antibiotic therapy
- Source identification and clearance
- appropriate surgical intervention
Describe use of fluclox in S.Aureus infection
Minimum duration for uncomplicated S.Aureus is 14days
Describe use of vancomycin in S.Aureus infection
Not ideal as poor tissue penetration, slow bactericidal activity, inconvenient administration and side effects
Describe use of teicoplanin in S.Aureus infection
advantage in terms of single daily dosing and could be used three times weekly after appropriate loading
Describe use of linezolid in S.Aureus infection
bacteriostatic, synthetic oxazolidinone, good penetration into bone and excellent bioavailability
Describe use of daptomycin in S. Aureus infection
cyclic lipopeptide with rapid bactericidal activity against S.Aureus.
Well tolerated, advantage of once daily dosing
