CONTEXT: Antibiotics are frequently used in hospital but the appropriateness of prescriptions ranged between 25-50%. The intervention of infectious disease specialists (IDS) could improve the appropriateness of prescriptions and reduce their use. The impact of IDS has not been yet fully estimated using a randomized trial to compare the quality of care of patients who will benefit of the intervention.

OBJECTIVES: To show using a randomized trial that patients hospitalized in emergency wards with IDS advice will receive more appropriate antimicrobial therapy but less exposure to antibiotics, as compared to patients who will not receive IDS advice.

METHODS: Prospective randomized trial comparing antibiotic exposure and appropriateness of prescriptions in two groups of patients admitted in emergency wards:

Control group: antibiotic prescriptions will be initiated and managed by the attending physicians Intervention group: antibiotic prescriptions will be systematically evaluated by the IDS and changed if judged necessary by the attending physicians, following IDS' advice.

STUDY PROCESS: The study will took place in the emergency wards of 4 university hospitals. For each ward, the period of the study will be 2 x 4 weeks.Total duration of the study: 12 months.

Inclusion Criteria:

• Adults Hospitalized in emergency wards Receiving antimicrobial therapy for active infection or prolonged surgical prophylaxis Therapy prescribed by the attending ward physician

Exclusion Criteria:

• Patients receiving antimicrobial therapy not prescribed by the attending ward physician