de Lastours V, et al. - In hospitalized patients either treated by ceftriaxone alone or receiving no antibiotics, researchers examine whether ceftriaxone may promote the emergence of commensal AmpC-overproducing Enterobacteriaceae because of a high biliary excretion. Findings suggest that in over a quarter of patients, treatment by ceftriaxone alone promotes the gut colonization by AmpC-overproducing Enterobacteriaceae, with a persistent carriage after the end of antibiotic exposure. They suggested not underestimating the ecological impact of ceftriaxone.