Evaluation of the Impact of the Modification of Antibiotic Susceptibility Testing on Antibiotic Prescriptions

Modification of Antibiotic Susceptibility Testing: Evaluation of the Impact of This Change on Antibiotic Prescriptions at the Nancy Regional University Hospital

As of 2019, the CA-SFM (Comité de l'Antibiogramme de la Société Française de Microbiologie) recommends that the letter "I" or the term "intermediate" on antibiotic antibiograms. Instead, it is recommended that the term "sensible à forte posologie" or "SFP". These recommendations have been in place since 21/01/2022 at Nancy University Hospital.

Pseudomonas aeruginosa is the bacterium most affected by this change, as it has a high proportion of "high dosage" antibiotics.

Staphylococcus aureus is the most widely isolated bacterium, and also impacted by the change in antibiotic susceptibility testing.

The aim of this change in recommendations is to guarantee the efficacy of the proposed molecules.

Main objective Evaluate the impact of the change in antibiogram recommendations in samples positive for Pseudomonas aeruginosa and Staphylococcus aureus on antibiotic therapy (prescribed dosage)

Secondary objectives

• Evaluate the impact of changing the way antibiograms in Pseudomonas aeruginosa and Staphylococcus aureus on antibiotic therapy (molecule prescribed).
• Evaluate the impact of changing the way antibiograms on antibiotic therapy (molecule and dosage prescribed), depending on the strain identified (Pseudomonas aeruginosa or Staphylococcus aureus).
• Describe the impact of changing antibiograms in Pseudomonas aeruginosa and Staphylococcus aureus on antibiotic therapy (molecule and dosage prescribed) by department.

Inclusion Criteria:

• Patients hospitalized with a positive monobacterial P. aeruginosa or S.aureus resulting in an antibiotic susceptibility test between 01/03/2021 and 31/08/2021 (AVANT period) and between 01/03/2022 and 31/08/2022 (AFTER period)

Exclusion Criteria:

• patients from the maternity unit / the Centre Chirurgical Emile Gallé (CCEG) / dialysis department (UF 1094)
• patients with sample results that did not result in a prescription of antibiotics documented and duplicate samples relating to the same pathology and the same documented treatment
• patient opposed to research