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Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus (MRSA) in Rat
07:46

Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus (MRSA) in Rat

Published on: June 4, 2012

Methicillin resistance and risk factors for embolism in Staphylococcus aureus infective endocarditis

Ron-Bin Hsu1, Fang-Yue Lin

  • 1Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan, Republic of China.

Infection Control and Hospital Epidemiology
|June 15, 2007
PubMed
Abstract

Insights

Methicillin-resistant Staphylococcus aureus (MRSA) endocarditis showed a lower embolism risk in left-sided infections but did not increase in-hospital death. Key embolism risks include drug use and large vegetations.

Area of Science:

  • Infectious Diseases
  • Cardiology
  • Microbiology

Background:

  • Staphylococcus aureus infective endocarditis (IE) carries a high risk of embolic events and neurological complications.
  • The impact of methicillin resistance on embolism risk in S. aureus IE remains unclear.

Purpose of the Study:

  • To assess the association between methicillin resistance in S. aureus IE and the risk of embolic episodes.
  • To identify independent risk factors for embolism in patients with S. aureus IE.

Main Methods:

  • Retrospective chart review of 123 patients with S. aureus IE between 1995 and 2005.
  • Comparison of data between methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) IE.
  • Logistic regression analysis to determine independent risk factors for embolism.

Main Results:

  • Embolism occurred in 37% of patients; cerebral embolism in 17% and pulmonary embolism in 18%.
  • Independent risk factors for embolism included injection drug use, cardiac vegetation size (≥10 mm), and non-nosocomial infection.
  • MRSA infection was associated with a decreased risk of embolism in left-sided endocarditis but not with in-hospital death.

Conclusions:

  • Methicillin resistance in S. aureus IE is linked to a reduced risk of embolism in left-sided cases.
  • Methicillin resistance did not significantly impact in-hospital mortality for S. aureus IE.
  • Vegetation size and drug use remain critical factors influencing embolic risk in S. aureus endocarditis.

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