Effect of Administration of 3rd Generation Cephalosporin on the Digestive Carrying of 3rd Generation Cephalosporin-resistant Enterobacteriaceae (CEF-IMPACT)

Inclusion Criteria: * Age ≥ 18 years old * Indication for antibiotic treatment with a 3rd generation injectable cephalosporin (cefotaxime or ceftriaxone) * Signed Informed Consent Exclusion Criteria: * Hypersensitivity to ceftriaxone or cefotaxime, to another cephalosporin or to any of the excipients of the specialities concerned. * History of severe hypersensitivity (e.g., anaphylactic reaction) to another class of antibacterial agent of the beta-lactam family (penicillins, monobactams and carbapenes) * Subcutaneous administration of ceftriaxone * Pregnant and breastfeeding woman * Suspicion of Pseudomonas infection or documented Pseudomonas infection requiring ceftazidime treatment * Suspicion of group III enterobacteriaceae infection or group III enterobacteriaceae infection requiring cefepime treatment