title: [Bacterial meningitis due to gram-negative bacilli in adults].
abstract: BACKGROUND
  Gram-negative bacilli are causative agents of bacterial meningitis in the neonatal period but rarely cause meningitis in adults without risk factors.
  
  
  OBJECTIVE
  To report on meningitis due to gram-negative bacilli (MGNB) in adults diagnosed in a hospital over a 25-year period.
  
  
  METHODS
  We reviewed the medical records of all patients with an age > or = 14 years who had been diagnosed with MGNB between 1982 and 2006.
  
  
  RESULTS
  Fifteen cases of MGNB are included (10.5% of the cases of bacterial meningitis with an identified aetiology), with a mean age of 48 years (14-79). Twelve (80%) were post-operative: recent neurosurgery (9 cases, 75%) and having a neurosurgical device (8 cases, 67%) were risk factors. Three (20%) were spontaneous: two were of a urinary origin and one had an undetermined origin. The aetiology was: Pseudomonas aeruginosa (3 cases), Escherichia coli (3 cases), Enterobacter aerogenes (2 cases), Pseudomonas fluorescens (1 case), Klebsiella pneumoniae (1 case), Morganella morganii (1 case), Acinetobacter anitratus (1 case), Acinetobacter iwoffii (1 case) and Flavobacterium brevis (1 case); in one patient with Gram positive staining for gram-negative bacilli, the culture was negative, and three of them (20%) were mixed infections (Staphylococcus spp.). Three patients (20%) died.
  
  
  CONCLUSIONS
  In adults, gram-negative bacilli rarely cause spontaneous meningitis, but are a common causation of post-neurosurgical meningitis and in those with neurosurgical devices. The mortality rate of MGNB is high.
authors.affiliation: Servicio de Medicina Interna, Hospital Universitario Puerta de Hierro, Majadahonda, Madrid, España. pld02m@saludalia.com
authors.forename: Pedro
authors.initials: P
authors.lastname: Laguna-del Estal
authors.forename: Pablo
authors.initials: P
authors.lastname: García-Montero
authors.forename: María
authors.initials: M
authors.lastname: Agud-Fernández
authors.forename: María
authors.initials: M
authors.lastname: López-Cano Gómez
authors.forename: Ana
authors.initials: A
authors.lastname: Castañeda-Pastor
authors.forename: Carlos
authors.initials: C
authors.lastname: García-Zubiri
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006090:Gram-Negative Bacteria / Q000472:pathogenicity*; D006801:Humans; D008297:Male; D016920:Meningitis, Bacterial / Q000175:diagnosis / Q000382:microbiology* / Q000401:mortality / Q000503:physiopathology; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult