The goal of this observational study is to learn about the eravacycline combination therapy in multidrug-resistant acinetobacter gaumannii pneumonia. The main question is to evaluate the the effectiveness and safety.

Participants will be given Eravacycline and Polymyxin，or other antibiotcs that the Investigator considered suitable. During the clinical trial, participants will be monitored for blood drug concentrations and drug concentrations in the ELF (Epithelial Lining Fluid。Clinical efficacy rate and microbiological clearance rate will be assessed at the same time

Inclusion Criteria:

1. ≥18 years old;
2. Meets the diagnostic criteria for pneumonia specified by the Chinese Medical Association Respiratory Branch.
3. CRAB is identified or predominant pathogenic bacteria, and drug sensitivity test indicates that Eravacycline is sensitive to the strain;
4. Patients expected to receive Eravacycline for ≥4 days;
5. Has already signed the informed consent

Exclusion Criteria:

1. Pregnant or lactating;
2. Concurrent intracranial infection, urinary tract infection, or bloodstream infection;
3. Individuals in a moribund state;
4. The investigator believes there is any medical history, current condition, treatment, laboratory abnormalities, or other circumstances that may affect the trial results, interrupt the trial process (or the subject's inability to complete all trial requirements, operations, and visits), or increase the subject's risk with the experimental medication. Patients with terminal illnesses or evidence of immediately life-threatening diseases are excluded;
5. Patients with a history of allergic reactions to tetracyclines or any excipients in the investigational drug formulation

This study plans to include patients diagnosed with CRAB pneumonia who seek medical attention at the Intensive Care Medicine Department of Fujian Medical University Union Hospital from January 2024 to April 2024