The IRIDICA PCR/Electrospray Ionization-Mass Spectrometry Assay on Bronchoalveolar Lavage for Bacterial Etiology in Mechanically Ventilated Patients with Suspected Pneumonia - PubMed (original) (raw)

The IRIDICA PCR/Electrospray Ionization-Mass Spectrometry Assay on Bronchoalveolar Lavage for Bacterial Etiology in Mechanically Ventilated Patients with Suspected Pneumonia

Kristoffer Strålin et al. PLoS One. 2016.

Abstract

We studied the diagnostic performance of the IRIDICA PCR/electrospray ionization-mass spectrometry (PCR/ESI-MS) assay applied on bronchoalveolar lavage (BAL) samples, from 51 mechanically ventilated patients with suspected pneumonia, in a prospective study. In 32 patients with X-ray verified pneumonia, PCR/ESI-MS was positive in 66% and BAL culture was positive in 38% (p = 0.045), and either of the methods was positive in 69%. The following BAL result combinations were noted: PCR/ESI-MS+/culture+, 34%; PCR/ESI-MS+/culture-, 31%; PCR/ESI-MS-/culture+, 3.1%; PCR/ESI-MS-/culture-, 31%; kappa 0.36 (95% confidence interval (CI), 0.10-0.63). In pneumonia patients without prior antibiotic treatment, optimal agreement was noted with 88% PCR/ESI-MS+/culture+ and 12% PCR/ESI-MS-/culture- (kappa 1.0). However, in patients with prior antibiotic treatment, the test agreement was poor (kappa 0.16; 95% CI, -0.10-0.44), as 10 patients were PCR/ESI-MS+/culture-. In 8/10 patients the pathogens detected by PCR/ESI-MS could be detected by other conventional tests or PCR tests on BAL. Compared with BAL culture, PCR/ESI-MS showed specificities and negative predictive values of ≥87% for all individual pathogens, an overall sensitivity of 77% and positive predictive value (PPV) of 42%. When other conventional tests and PCR tests were added to the reference standard, the overall PPV increased to 87%. The PCR/ESI-MS semi-quantitative level tended to be higher for PCR/ESI-MS positive cases with pneumonia compared with cases without pneumonia (p = 0.074). In conclusion, PCR/ESI-MS applied on BAL showed a promising performance and has potential to be clinically useful in mechanically ventilated patients with suspected pneumonia. The usefulness of the method for establishment of pneumonia etiology and selection of antibiotic therapy should be further studied.

PubMed Disclaimer

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist. The fact that Abbott provided an instrument and test kits for the study does not alter the authors’ adherence to PLOS ONE policies on sharing data and materials.

Figures

Fig 1

Fig 1. Flow shart of the study patients.

ICU, intensive care unit; BAL, bronchoalveolar lavage.

Fig 2

Fig 2. Semi-quantitative levels of IRIDICA PCR/electrospray ionization-mass spectrometry (PCR/ESI-MS) on bronchoalveolar lavage (BAL).

(A) Results of cases with and without pneumonia; (B) Results related to other microbiological results. Black triangles, pneumonia; white triangles, not pneumonia. CFU, colony-forming units.

References

    1. Iregui M, Ward S, Sherman G, Fraser VJ, Kollef MH. Clinical importance of delays in the initiation of appropriate antibiotic treatment for ventilator-associated pneumonia. Chest. 2002; 122:262–8. -PubMed
    1. Jones RN. Microbial etiologies of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia. Clin Infect Dis. 2010; 51 Suppl 1:S81–7. 10.1086/653053 -DOI -PubMed
    1. Musher DM, Thorner AR. Community-acquired pneumonia. N Engl J Med. 2014; 371:1619–28. 10.1056/NEJMra1312885 -DOI -PubMed
    1. Cooper GM, Jones JJ, Arbique JC, Flowerdew GJ, Forward KR. Intra and inter technologist variability in the quality assessment of respiratory tract specimens. Diagn Microbiol Infect Dis. 2000; 37:231–5. -PubMed
    1. Guidelines for the management of adults with hospital-acquired, ventilator-associated, and healthcare-associated pneumonia. Am J Respir Crit Care Med. 2005; 171:388–416. -PubMed

Publication types

MeSH terms

LinkOut - more resources