title: New procedure to reduce the time and cost of broncho-pulmonary specimen management using the Previ Isola® automated inoculation system.
abstract: The microbiological diagnosis of respiratory tract infections requires serial manual dilutions of the clinical specimen before agar plate inoculation, disrupting the workflow in bacteriology clinical laboratories. Automated plating instrument systems have been designed to increase the speed, reproducibility and safety of this inoculating step; nevertheless, data concerning respiratory specimens are lacking. We tested a specific procedure that uses the Previ Isola® (bioMérieux, Craponne, France) to inoculate with broncho-pulmonary specimens (BPS). A total of 350 BPS from a university-affiliated hospital were managed in parallel using the manual reference and the automated methods (expectoration: 75; broncho-alveolar lavage: 68; tracheal aspiration: 17; protected distal sample: 190). A specific enumeration reading grid, a pre-liquefaction step and a fluidity test, performed before the inoculation, were designed for the automated method. The qualitative (i.e., the number of specimens yielding a bacterial count greater than the clinical threshold) and quantitative (i.e., the discrepancy within a 0.5 log value) concordances were 100% and 98.2%, respectively. The slimmest subgroup of expectorations could not be managed by the automated method (8%, 6/75). The technical time and cost savings (i.e., number of consumed plates) reached 50%. Additional studies are required for specific populations, such as cystic fibrosis specimens and associated bacterial variants. An automated decapper should be implemented to increase the biosafety of the process. The PREVI Isola® adapted procedure is a time- and cost-saving method for broncho-pulmonary specimen processing.
authors.affiliation: Laboratoire de Bactériologie-Hygiène, département de Virologie, Bactériologie-Hygiène, Parasitologie-Mycologie, Assistance Publique-Hôpitaux de Paris, Centre Hospitalier Universitaire Henri Mondor, Créteil, France.
authors.forename: Biba
authors.initials: B
authors.lastname: Nebbad-Lechani
authors.forename: Aurélie
authors.initials: A
authors.lastname: Emirian
authors.forename: Fabienne
authors.initials: F
authors.lastname: Maillebuau
authors.forename: Nadia
authors.initials: N
authors.lastname: Mahjoub
authors.forename: Vincent
authors.initials: V
authors.lastname: Fihman
authors.forename: Patrick
authors.initials: P
authors.lastname: Legrand
authors.forename: Jean-Winoc
authors.initials: JW
authors.lastname: Decousser
mesh_terms: D057205:Automation, Laboratory / Q000191:economics / Q000379:methods*; D001424:Bacterial Infections / Q000175:diagnosis* / Q000382:microbiology; D001431:Bacteriological Techniques / Q000379:methods*; D012634:Bodily Secretions / Q000382:microbiology*; D003365:Costs and Cost Analysis; D006785:Hospitals, University; D015203:Reproducibility of Results; D012141:Respiratory Tract Infections / Q000175:diagnosis* / Q000382:microbiology; D013048:Specimen Handling / Q000191:economics / Q000379:methods*; D013997:Time Factors
keywords: Automation; Bacteriology laboratory; Inoculation; Previ Isola®; Respiratory specimen