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 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:

• 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 4 university hospitals. Two medical or surgical wards will participate by hospital. 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 surgical or medical 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