Figure 4

Increased relative abundance of a bacterial species increases the likelihood that the species will be cultured. Each dot represents the detection of the species by 16S deep sequencing. Species that were detected by culture (response = 1) are represented by dots at the top of the figure, and species that were not cultured (response = 0) are represented as dots at the bottom of the figure. The proportion of occurrences that were detected by culture was modeled as a function of the observed relative abundance (as determined using molecular testing) using logistic regression (indicated by the blue line). The shaded region indicates the 95% confidence interval of the predicted proportion. The trend was significantly positive for Pseudomonas aeruginosa (OR = 1.17; 95% CI, 1.08-1.31) and Staphylococcus aureus (OR = 1.08; 95% CI, 1.03-1.15), and it approached significance for Enterococcus faecalis (OR = 1.05; 95% CI, 0.98-1.16). The results demonstrate that an increased relative abundance of one of these species within a sample subsequently increases the likelihood that the species will be cultured.