Impact of Rapid Pathogen Detection in ICU Patients With Suspected Pneumonia on Antimicrobial Therapy

Inclusion Criteria: * adult (≥18 years old) ICU patients * mechanical ventilation * new antibiotic prescription within 24 hours for suspected community acquired, healthcare or ventilator associated pneumonia * suspected pneumonia is defined as any of purulent sputum, cough, fever, shortness of breath, hypoxia, hypercapnia or abnormal white cell count AND chest infiltrates on imaging * need for antibiotics other than suspected respiratory infection * aspiration pneumonia * suspected pneumonia due to tuberculosis * known respiratory pathogens within 7 days prior to randomization * given empirical antimicrobials for suspected Stenotrophomonas infection * lack of sufficient respiratory samples for culture and FA Pneumonia Panel * not expected to survive beyond 48 hours * limitation of therapy prior to recruitment * prisoners * allergy to antibiotics * immunosuppression from long term steroid of at least 5 mg/day or chemotherapy or HIV or haematological disease * pregnancy