title: Evaluation of an immunomagnetic separation assay in combination with cultivation to improve Legionella pneumophila serogroup 1 recovery from environmental samples.
abstract: OBJECTIVE
  Legionella isolation from environmental samples is often difficult because of the presence of heterotrophic-associated bacteria that frequently overgrow when using standard culture (ISO 11731, 1998; NF T90-431, 2003) methods. To improve Legionella pneumophila recovery from complex water samples (water from cooling towers, biofilms), we evaluated an immunomagnetic separation (IMS) assay using a monoclonal antibody raised against the lipopolysaccharide of Leg. pneumophila sg1 in combination with culture.
  
  
  RESULTS
  This study was conducted on 51 environmental specimens. The comparison between IMS-culture and standard culture (ISO 11731, 1998; NF T90-431, 2003) methods was made using ISO 17994, 2004 criteria for establishing equivalence between microbiological methods based on the upper and lower (XH and XL) values of the relative difference (95% confidence limit) and D as maximum acceptable deviation (value of the confidence limit).
  
  
  CONCLUSIONS
  We found that the average performance of IMS culture was higher than the reference method.
authors.affiliation: Université de Lyon; 42023 Université de Saint-Etienne; Groupe Immunité des Muqueuses et Agents Pathogènes, EA 3064, Faculté de Médecine,
authors.forename: S
authors.initials: S
authors.lastname: Allegra
authors.forename: F
authors.initials: F
authors.lastname: Girardot
authors.forename: F
authors.initials: F
authors.lastname: Grattard
authors.forename: P
authors.initials: P
authors.lastname: Berthelot
authors.forename: J H
authors.initials: JH
authors.lastname: Helbig
authors.forename: B
authors.initials: B
authors.lastname: Pozzetto
authors.forename: S
authors.initials: S
authors.lastname: Riffard
mesh_terms: D018441:Biofilms; D004783:Environmental Microbiology; D018189:Immunomagnetic Separation / Q000379:methods*; D016952:Legionella pneumophila / Q000145:classification / Q000276:immunology / Q000302:isolation & purification*; D065288:Serogroup; D014871:Water Microbiology