title: Clinical and microbiological features of infective endocarditis caused by aerococci.
abstract: OBJECTIVE
  To define the clinical presentation of aerococcal infective endocarditis (IE) and the prevalence of synergy between penicillin and gentamicin on aerococcal isolates.
  
  
  METHODS
  Cases of aerococcal IE between 2002 and 2014 were identified in the Swedish Registry of Infective Endocarditis (SRIE). MALDI-TOF MS was used to confirm species determination. The medical records were analysed and compared to cases reported to the SRIE caused by other pathogens.
  
  
  RESULTS
  Sixteen cases of aerococcal IE, fourteen with Aerococcus urinae and two with Aerococcus sanguinicola, were confirmed. Etest-based methods and time-kill experiments suggested synergy between penicillin and gentamicin towards seven of fifteen isolates. The patients with aerococcal IE were significantly older than those with streptococci or Staphylococcus aureus IE. Most of the patients had underlying urinary tract diseases or symptoms suggesting a urinary tract focus of the infection. Seven patients with aerococcal IE presented with severe sepsis but ICU treatment was needed only in one patient and there was no fatality. Valve exchange surgery was needed in four patients and embolization was seen in three patients.
  
  
  CONCLUSIONS
  This report is the largest on aerococcal IE and suggests that the prognosis is relatively favourable despite the fact that the patients are old and have significant comorbidities.
authors.affiliation: Division of Infection Medicine, Department of Clinical Sciences, Lund University, Tornavägen 10, BMC B14, 221 84, Lund, Sweden.
authors.forename: Torgny
authors.initials: T
authors.lastname: Sunnerhagen
authors.affiliation: Clinical Microbiology, Labmedicin, Region Skåne, Lund, Sweden.|Department of Laboratory Medicine Lund, Section of Medical Microbiology, Lund University, Lund, Sweden.
authors.forename: Bo
authors.initials: B
authors.lastname: Nilson
authors.affiliation: Department of Infectious Diseases, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.|Swedish Registry of Infective Endocarditis, Swedish Society of Infectious Diseases, Gothenburg, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Olaison
authors.affiliation: Division of Infection Medicine, Department of Clinical Sciences, Lund University, Tornavägen 10, BMC B14, 221 84, Lund, Sweden. magnus.rasmussen@med.lu.se.
authors.forename: Magnus
authors.initials: M
authors.lastname: Rasmussen
mesh_terms: D056570:Aerococcus / Q000737:chemistry / Q000145:classification / Q000187:drug effects / Q000302:isolation & purification*; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D052978:Disk Diffusion Antimicrobial Tests; D004357:Drug Synergism; D004696:Endocarditis / Q000382:microbiology / Q000473:pathology*; D005260:Female; D005839:Gentamicins / Q000494:pharmacology; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010406:Penicillins / Q000494:pharmacology; D011379:Prognosis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013548:Sweden
chemical_list: D000900:Anti-Bacterial Agents; D005839:Gentamicins; D010406:Penicillins
keywords: Aerococcus; Aerococcus sanguinicola; Aerococcus urinae; Infective endocarditis; Prognosis; Synergy