Staphylococcus haemolyticus endocarditis: clinical and microbiologic analysis of 4 cases

Diagn Microbiol Infect Dis. 2007 Mar;57(3):325-31. doi: 10.1016/j.diagmicrobio.2006.08.019. Epub 2006 Dec 1.

Abstract

Only 3 cases of infective endocarditis (IE) due to methicillin-resistant Staphylococcus haemolyticus (MRSH) have been reported in English literature. Here we report 4 cases of IE due to MRSH encountered in a single university hospital. Population analysis of the strains was performed to assess the presence of vancomycin/teicoplanin heteroresistant subpopulations. Pulsed-field gel electrophoresis was used for molecular typing of isolates. IE was defined in 3 cases as health care associated, and in 1 case, as community acquired. A causative strain was lost. Two strains were heteroresistant to teicoplanin, and 1 also to vancomycin. Genome macrorestriction profile studies demonstrated that 2 MRSH isolates belonged to clones A and E, possessing a class C1 mecDNA, whereas 1 clone was sporadic. All patients were treated with vancomycin plus rifampin. Two patients were cured with antibiotic therapy alone, 1 patient needed surgery, and 1 patient died. Methicillin-resistant multiresistant S. haemolyticus may represent a difficult-to-treat cause of both community and nosocomially acquired IE.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Anti-Bacterial Agents
  • Aortic Valve / microbiology*
  • Bacteremia / microbiology
  • Drug Therapy, Combination
  • Electrophoresis, Gel, Pulsed-Field
  • Endocarditis, Bacterial / drug therapy
  • Endocarditis, Bacterial / microbiology*
  • Female
  • Humans
  • Male
  • Methicillin Resistance*
  • Rifampin / therapeutic use
  • Staphylococcal Infections / drug therapy
  • Staphylococcal Infections / microbiology*
  • Staphylococcus haemolyticus / drug effects
  • Staphylococcus haemolyticus / genetics
  • Staphylococcus haemolyticus / pathogenicity*
  • Vancomycin / therapeutic use

Substances

  • Anti-Bacterial Agents
  • Vancomycin
  • Rifampin