There is broad agreement between qualitative bacterial culture results and 454 pyrosequencing for dominant CF pathogens.

<p>The fraction of sequence assigned to the genus (a) <i>Pseudomonas</i> or (b) <i>Burkholderia</i> are plotted for each patient and sample timepoint as a function of the patient' s reported culture status for the recognized CF pathogens <i>P. aeruginosa</i> and <i>B. cepacia</i> complex species. Patient samples are color-coded by timepoint (green, onset of exacerbation; red, end-of-treatment for exacerbation with intravenous antibiotics; blue, clinically stable interval). Patient 19 was culture negative for both <i>P. aeruginosa</i> and <i>B. cepacia</i>.