title: [Primary Neisseria meningitidis arthritis of the knee without meningitis: contribution of synovial fluid culture in blood-culture vial].
abstract: BACKGROUND
  Primary meningococcal arthritis is a rare form of meningococcal disease. It occurs as an isolated acute purulent arthritis without meningitis, and presence of Neisseria meningitidis in articular fluid. We report a new case of typical primary meningococcal arthritis.
  
  
  METHODS
  A previously healthy 23-year-old female patient was admitted for purpuric lesions of the legs. At admission, conscience was normal and symptoms of meningitis were absent. During the 2nd day of hospitalisation, a warm and painful effusion in the right knee appeared. Aspiration from the right knee yielded a purulent fluid. N. meningitidis was isolated from a blood-culture vial inoculated with the synovial fluid, while blood cultures remained sterile. Anti-biotherapy was initiated as soon as microbiological diagnosis was established. The patient was symptom-free 1 month later.
  
  
  CONCLUSIONS
  We emphasize the fact that agar cultures of the synovial fluid remained sterile, while N. meningitidis grew in a blood-culture vial. We suggest that diagnosis of primary meningococcal arthritis may be underestimated when inappropriate culture media are used.
authors.affiliation: Service d'hémato-séro-bactériologie, CHI Poissy-Saint-Germain-en-Laye, 20, rue Amargis, BP 231, 78105 Saint-Germain-en-Laye, France.
authors.forename: G L
authors.initials: GL
authors.lastname: Cartolano
authors.forename: Z
authors.initials: Z
authors.lastname: Le Lostec
authors.forename: M
authors.initials: M
authors.lastname: Chéron
authors.forename: A
authors.initials: A
authors.lastname: Boisivon
authors.forename: Y
authors.initials: Y
authors.lastname: Welker
authors.forename: P
authors.initials: P
authors.lastname: Mornet
mesh_terms: D000328:Adult; D001170:Arthritis, Infectious / Q000175:diagnosis / Q000473:pathology*; D001800:Blood Specimen Collection; D015169:Colony Count, Microbial; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000382:microbiology*; D008589:Meningococcal Infections / Q000175:diagnosis / Q000473:pathology*; D009345:Neisseria meningitidis / Q000302:isolation & purification*; D013582:Synovial Fluid / Q000382:microbiology
vernacular_title: Monoarthrite du genou à Neisseria meningitidis sans méningite: apport de la culture du liquide articulaire en flacon d'hémoculture.