Derivation and Validation of the Risk Evaluation Score for Pneumonia Involving Resistant Entities (RESPIRE)

Inclusion Criteria: All patients: * aged ≥18 years * who underwent respiratory sample collection within 48 hours of hospital admission and had subsequent positive culture results oleading to a confirmed etiological diagnosis of community-acquired pneumonia (CAP) * Pneumonia was clinically defined by the presence of two or more clinical signs or symptoms (body temperature \<36.0°C or \>38.0°C; respiratory rate \>20 breaths/min; oxygen saturation on room air \<90%; arterial partial pressure of oxygen \<60 mmHg; cough; sputum production; white blood cell count \<4,000/μL or \>10,000/μL; bandemia \>10%), in addition to radiographic evidence of a new parenchymal opacity or cavitation. * Only patients with positive respiratory culture results were included in the analysis. During the prospective phase, only patients whose microbiological samples were collected in the Emergency Department were enrolled. Exclusion Criteria: * informed consent was not provided * age was \<18 years or \>90 years * pregnant * pneumonia occurred after more than 48 hours from hospital admission (hospital-acquired pneumonia).