A Study on Integrated Chinese and Western Medicine for Severe Pneumonia Caused by Multidrug-Resistant Gram-Negative Bacterial Infections

Inclusion Criteria: * Meeting the diagnostic criteria for severe pneumonia, aged ≥18 years and \<80 years; * Microbiological culture confirming Gram-negative bacterial infection resistant to three or more classes of antibiotics, such as extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, carbapenem-resistant Enterobacteriaceae, carbapenem-resistant Acinetobacter baumannii (CRAB), and multidrug-resistant Pseudomonas aeruginosa (MDR-PA); * Written informed consent obtained from the patient or their legal representative. Exclusion Criteria: * Pregnant or breastfeeding women; * Patients with impaired consciousness, dementia, psychiatric disorders, or other conditions that preclude effective communication and cooperation; * Patients with aspiration pneumonia, fungal pneumonia, viral pneumonia, pulmonary tuberculosis, or HIV-associated Pneumocystis jirovecii pneumonia; * Patients with severe hepatic or renal insufficiency, such as liver cirrhosis with Child-Pugh score of 10-15, or estimated glomerular filtration rate (eGFR) \<30 mL/min/1.73 m²; * Patients with hematologic malignancies, solid organ transplantation, or congenital/acquired diseases leading to immunodeficiency; * Patients with multidrug-resistant bacterial infections outside the lung (e.g., urinary tract, abdominal cavity, bloodstream); * Patients with severe cardiac dysfunction (NYHA class IV), malignant arrhythmias, or other hemodynamically unstable conditions; * Patients who have already received antimicrobial therapy for more than one week; * Patients who have participated in another drug clinical trial within one month prior to enrollment; * Patients with known allergy to the investigational drug.