title: FilmArray Respiratory Panel Assay: Comparison of Nasopharyngeal Swabs and Bronchoalveolar Lavage Samples.
abstract: The FilmArray respiratory panel (FARP) reliably and rapidly identifies 17 viruses and 3 bacterial pathogens. A nasopharyngeal swab FARP (NP FARP) is performed for many patients with respiratory symptoms. For patients who are acutely ill or immunocompromised or fail to improve, a bronchoalveolar lavage sample FARP (BAL FARP) is performed in addition to the NP FARP. To date, no studies have compared the yield of a BAL FARP with that of an NP FARP. We retrospectively studied all patients who had a BAL FARP within 7 days after an NP FARP between June 2013 and May 2014. Demographic information, comorbidities, FARP results, and all microbiologic data from BAL fluid were collected. Eighty-six patients had a BAL FARP performed within 7 days (mean, 1.6; median, 1) after an NP FARP. Of these, 66 (77%) had concordant BAL and NP FARP results: 15 (23%) had the same pathogen identified from the NP and BAL FARPs, and 51 (77%) had concordant negative FARP results. In 18 of the 86 patients (21%), a pathogen was detected from the NP FARP; of these, 15 (83%) had a concordant match on a subsequent BAL FARP, and the remaining 3 had negative BAL FARPs. In 17 of the 86 patients (20%), pathogens were identified from the BAL FARPs that were not detected by the NP FARPs; of these, 16 (94%) had initial negative NP FARPs. The data suggest that once a pathogen is identified by an NP FARP, a subsequent BAL FARP is unlikely to add new microbiologic information. However, a BAL FARP may provide new, useful microbiologic information when performed within 7 days after a negative NP FARP.
authors.affiliation: Department of Internal Medicine, Mayo Clinic, Phoenix, Arizona, USA.
authors.forename: Natalya
authors.initials: N
authors.lastname: Azadeh
authors.affiliation: Division of Pulmonary Medicine, Mayo Clinic, Phoenix, Arizona, USA.
authors.forename: Kenneth K
authors.initials: KK
authors.lastname: Sakata
authors.affiliation: Department of Internal Medicine, Mayo Clinic, Phoenix, Arizona, USA.
authors.forename: Anjuli M
authors.initials: AM
authors.lastname: Brighton
authors.affiliation: Division of Infectious Diseases, Mayo Clinic, Phoenix, Arizona, USA.
authors.forename: Holenarasipur R
authors.initials: HR
authors.lastname: Vikram
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Phoenix, Arizona, USA grys.thomas@mayo.edu.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Grys
mesh_terms: D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology* / Q000821:virology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D060885:Multiplex Polymerase Chain Reaction / Q000379:methods; D009305:Nasopharynx / Q000382:microbiology* / Q000821:virology*; D016133:Polymerase Chain Reaction / Q000379:methods; D012141:Respiratory Tract Infections / Q000175:diagnosis* / Q000382:microbiology / Q000821:virology; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*