Broad-Range Detection of Microorganisms Directly from Bronchoalveolar Lavage Specimens by PCR/Electrospray Ionization-Mass Spectrometry

• Published in: PloS one Vol. 12; no. 1; p. e0170033
• Main Authors: Ullberg, Måns, Lüthje, Petra, Mölling, Paula, Strålin, Kristoffer, Özenci, Volkan
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 2017; Public Library of Science (PLoS)
• Subjects: Alveoli; Antibiotics; Bacteria; Bacteria - classification; Bacteria - genetics; Bacteria - isolation & purification; Biology and Life Sciences; Bordetella pertussis; Bronchoalveolar lavage; Bronchoalveolar Lavage Fluid - microbiology; Bronchus; Candida; Causes of; Culture; Deoxyribonucleic acid; Diagnosis; Diagnostic systems; DNA; DNA, Bacterial - analysis; DNA, Bacterial - genetics; Electrospraying; Genetic aspects; Hospitals; Humans; Identification; Infectious diseases; Ionization; Laboratories; Legionella pneumophila; Legionnaires' disease bacterium; Lung Diseases - diagnosis; Lung Diseases - microbiology; Mass spectrometry; Mass spectroscopy; Medicin och hälsovetenskap; Medicine; Medicine and Health Sciences; Methods; Microbiology; Microorganisms; Mycoplasma pneumoniae; Pathogens; Pertussis; Pneumonia; Polymerase chain reaction; Polymerase Chain Reaction - methods; Research and Analysis Methods; Scientific imaging; Species; Spectrometry, Mass, Electrospray Ionization - methods; Spectroscopy; Staphylococcus; Staphylococcus aureus; Staphylococcus infections; Streptococcus infections; Streptococcus pneumoniae; Whooping cough; Sweden
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0170033

The clinical demand on rapid microbiological diagnostic is constantly increasing. PCR coupled to electrospray ionization-mass spectrometry, PCR/ESI-MS, offers detection and identification of over 750 bacteria and Candida species directly from clinical specimens within 6 hours. In this study, we investigated the clinical performance of the IRIDICA BAC LRT Assay for detection of bacterial pathogens in 121 bronchoalveolar lavage (BAL) samples that were received consecutively at our bacterial laboratory for BAL culture. Commensal or pathogenic microorganisms were detected in 118/121 (98%) BAL samples by PCR/ESI-MS, while in 104/121 (86%) samples by routine culture (P<0.01). Detection of potentially pathogenic microorganisms by PCR/ESI-MS was evaluated in comparison with conventional culture-based or molecular methods. The agreement between positive findings was overall good. Most Staphylococcus aureus-positive PCR/ESI-MS results were confirmed by culture or species-specific PCR (27/33, 82%). The identity of Streptococcus pneumoniae could however be confirmed for only 6/17 (35%) PCR/ESI-MS-positive samples. Non-cultivable and fastidious pathogens, which were not covered by standard culture procedures were readily detected by PCR/ESI-MS, including Legionella pneumophila, Bordetella pertussis, Norcadia species and Mycoplasma pneumoniae. In conclusion, PCR/ESI-MS detected a broad range of potential pathogens with equal or superior sensitivity compared to conventional methods within few hours directly from BAL samples. This novel method might thus provide a relevant tool for diagnostics in critically ill patients.