Fig. 4.

PAPs of ATCC 27853 with colistin monotherapy, colistin-plus-doripenem combination therapy, or neither antibiotic (control) at the 10⁶-CFU/ml inoculum (left panels) and the 10⁸-CFU/ml inoculum (right panels) at 24 h (A and B), 72 h (C and D), and 96 h (E and F). Baseline (0-h) PAPs are shown in all panels. Colonies growing on ≥4 mg/liter colistin are considered resistant. The y axis starts from the limit of detection, and the limit of quantification (LOQ) is indicated by the horizontal broken line.