2015 European Society of Cardiology Guidelines have proposed the combination of Ampicillin and Cloxacillin for initial empirical treatment of infective endocarditis in acute severely ill patients (before pathogen identification). Yet this combination has never been studied in clinical trials. High dose penicillin treatments are associated with a risk of nephrotoxicity.

The investigator's primary purpose is to describe patients treated with high dose Amoxicillin and Cloxacillin combination and to evaluate its renal tolerance.

Inclusion criteria:

• Adult patient (≥18 years old)
• Hospitalized at the Strasbourg University Hospital and treated concomitantly with Amoxicillin IV and Cloxacillin IV for ≥48 hours between January 1, 2016 and December 31, 2020.
• Patient not having expressed his opposition, after information, to the reuse of his data for scientific research purposes.

Exclusion criteria:

• Subject having expressed opposition to participating in the study
• Subject under guardianship, curatorship or safeguard of justice

Adult patient hospitalized at the Strasbourg University Hospital and treated concomitantly with Amoxicillin IV and Cloxacillin IV for ≥48 hours between January 1, 2016 and December 31, 2020.