title: Staphylococcus capraenative mitral valve infective endocarditis.
abstract: BACKGROUND
  Staphylococcus capraeis a rare cause of infective endocarditis. Here, we report a case involving the native mitral valve in the absence of an implantable cardiac electronic device.
  
  
  METHODS
  A 76-year-old man presented with a 2 week history of confusion and pyrexia. His past medical history included an open reduction and internal fixation of a humeral fracture 17 years previously, which remained non-united despite further revision 4 years later. There was no history of immunocompromise or farm-animal contact. Two sets of blood culture bottles, more than 12 h apart, were positive forS. caprae. Trans-thoracic echocardiography revealed a 1×1.2 cm vegetation on the mitral valve, with moderate mitral regurgitation. Due to ongoing confusion, he had a magnetic resonance imaging brain scan, which showed a subacute small vessel infarct consistent with a thromboembolic source. A humeral SPECT-CT (single-photon emission computerized tomography-computerized tomography) scan showed no clear evidence of acute osteomyelitis. Surgical vegetectomy and mitral-valve repair were considered to reduce the risk of further systemic embolism and progressive valve infection. However, the potential risks of surgery to this patient led to a decision to pursue a cure with antibiotic therapy alone. He remained well 3 months after discharge, with repeat echocardiography demonstrating a reduction in the size of the vegetation (0.9 cm).
  
  
  CONCLUSIONS
  Management of this infection was challenging due to its rarity and its unclear progression, complicated by the dilemma surrounding surgical intervention in a patient with a complex medical background.
authors.affiliation: Edinburgh Heart Centre, Western General Hospital , Edinburgh , Scotland.
authors.forename: T'ng Choong
authors.initials: TC
authors.lastname: Kwok
authors.affiliation: Clinical Microbiology, Royal Infirmary Edinburgh , Edinburgh , Scotland.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Poyner
authors.affiliation: Clinical Microbiology, Royal Infirmary Edinburgh , Edinburgh , Scotland.
authors.forename: Ewan
authors.initials: E
authors.lastname: Olson
authors.affiliation: Edinburgh Heart Centre, Western General Hospital , Edinburgh , Scotland.
authors.forename: Peter
authors.initials: P
authors.lastname: Henriksen
authors.affiliation: Regional Infectious Diseases Unit, Western General Hospital , Edinburgh , Scotland.
authors.forename: Oliver
authors.initials: O
authors.lastname: Koch
keywords: Staphylococcus caprae; coagulase negative staphylococcus; conservative management; native valve; occult prosthetic metalwork infection