Fig. 2

In vitro growth of Clostridium difficile in stool suspensions of hospitalized patients, stratified by level of in vitro inhibitory activity against C. difficile based on a modification of the classification of Owens et al. (1). A total of 141 stool specimens from 98 patients were analyzed (1–3 per patient). Specimens were considered inhibitory if the concentration of C. difficile decreased or remained unchanged compared to the baseline concentration. The non-inhibitory antibiotics that were administered at the time stool specimens were collected included ciprofloxacin (N = 6), ceftriaxone (N = 5), and cephalexin (N = 1). The agents classified as other inhibitory antibiotics that were administered included imipenem (N = 6), meropenem (N = 5), ertapenem (N = 6), linezolid (N = 4), ampicillin/sulbactam (N = 3), and metronidazole (N = 2). SE, standard error. CFU, colony-forming unit