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Virulence of beta-hemolytic streptococci in infective endocarditis

Yvon Ruch1,2, Yves Hansmann3, Philippe Riegel4

  • 1Department of Infectious Disease, Strasbourg University Hospital, Strasbourg, France. yvon.ruch@gmail.com.

Infection
|September 15, 2019
PubMed
Abstract

Insights

Beta-hemolytic streptococci (BHS) infective endocarditis (IE) shows a more severe prognosis than alpha- or non-hemolytic streptococci (ANHS) IE. BHS IE warrants increased monitoring and aggressive treatment due to high mortality and complication rates.

Area of Science:

  • Infectious Diseases
  • Cardiology
  • Microbiology

Background:

  • Infective endocarditis (IE) is often caused by alpha- or non-hemolytic streptococci (ANHS).
  • Beta-hemolytic streptococci (BHS) can also cause IE, with current guidelines suggesting specific treatment modifications.
  • Comparative analysis of IE outcomes based on causative microorganisms is crucial for treatment strategies.

Purpose of the Study:

  • To compare morbidity and mortality rates in infective endocarditis (IE) based on the causative microorganism.
  • To evaluate the clinical outcomes associated with beta-hemolytic streptococci (BHS) IE versus other common causes.
  • To inform treatment guidelines regarding BHS endocarditis.

Main Methods:

  • Retrospective observational study conducted between 2012 and 2017.
  • Data collected from a single hospital in France.
  • Analysis of 316 definite IE episodes, focusing on in-hospital mortality, 1-year mortality, and complication rates.

Main Results:

  • Staphylococcal (26.7%) and BHS (25.0%) IE exhibited significantly higher in-hospital mortality compared to ANHS (9.4%) and enterococcal (10.9%) IE.
  • BHS IE cases showed higher rates of septic shock (29.2%) and cerebral emboli (29.2%) than ANHS IE.
  • Staphylococcal IE was the most frequent type (38%), followed by ANHS (25%), enterococcal (12%), and BHS (6%).

Conclusions:

  • Beta-hemolytic streptococci (BHS) infective endocarditis (IE) is associated with a more severe prognosis than ANHS IE.
  • The virulence of BHS in IE may be comparable to that of staphylococci.
  • Increased patient monitoring and consideration of aggressive treatments, such as early surgery, are recommended for BHS IE.
Keywords:
Beta-hemolyticCardiac surgeryInfective endocarditisStreptococciVirulence

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