Use of a Rapid Diagnostic Test for Antibiotic De-escalation in Severe Community Acquired Pneumonia

Inclusion Criteria: 1. Adults aged 18 years and older with known or suspected community-acquired pneumonia who are admitted to the MICU Service 2. Meets one of the following: 1. Have or plan to obtain a bronchoalveolar lavage (BAL) 2. Have or plan to obtain a quantitative endotracheal aspirate sample 3. Have already produced a high-quality sputum sample if not intubated 3. Primary MICU attending and fellow willing to base antibiotic therapy on results of RDT Exclusion Criteria: 1. Subjects with confirmed extrapulmonary infection requiring antibiotics outside the usual treatment for SCAP, with the exception of suspected uncomplicated urinary tract infection 2. Neutropenic fever, defined as absolute neutrophil count \<1000/mm3 and absence of infiltrate on available chest imaging 3. Chronic airway infection, defined as cystic fibrosis, lung transplant, or non-CF bronchiectasis 4. Patient/surrogate refusal 5. Inability to perform BAL, NBBAL, quantitative ETA, or produce a high-quality sputum sample prior to 48 hours from hospital admission