1. Lung function decline correlates with the evolution of clade C3 and mutations influencing LPS biosynthesis, motility, adhesion to surfaces, and cyclic diguanylate signaling.
Lung function decline correlates with the evolution of clade C3 and mutations influencing LPS biosynthesis, motility, adhesion to surfaces, and cyclic diguanylate signaling. Forced expiratory volume in 1 s (FEV1) (A) and forced expiratory flow over the middle half of the forced vital capacity (FEF25−75%) (C) as predicted percentages. Patient respirometry data and clinical microbiological reports from sputa were collected during a previous retrospective study (15) and were available 2 years prior to the detection of B. multivorans and in the subsequent 20 years of infection. Both linear and 4-parameter (4P) logistic functions (shown), as well as quadratic, cubic, and logistic 3-parameter and 5-parameter models (not shown), were fit to the data and evaluated for the greatest quality using the Akaike information criterion (AIC). The upward trend in FEV1 in the last 2 years slightly favored a cubic fit over other models (FEV1, linear AIC = 296.5, quadratic AIC = 292.4, logistic 5 parameters = 288.5, logistic 4 parameters = 287.2, cubic = 285.1), whereas the logistic 4-parameter model provided the best fit for FEF25−75% (linear = 307.5, quadratic = 303.0, logistic 5 parameters = 300.5, cubic = 299.4, logistic 4 parameters = [lower is better]). This supports a period of more rapid decline consistent with the rise of clade C3. (B) Temporal distribution of microorganisms (see Table S2 in the supplemental material) coinfecting the lungs of the CF patient under study, as well as the phylogenetic structure of the detected B. multivorans isolates.
Inês N. Silva et al. mSystems 2016; doi: /mSystems