Rapid Identification of Infectious Pathogens in Severe Pneumonia Guided by Bronchoscopic Imaging and Lung CT

N/ANot Yet RecruitingNCT07308340

The First Hospital of Jilin University400 enrolled

Overview

Severe pneumonia requires rapid and accurate diagnosis for targeted treatment, but single lung CT has limitations in identifying pathogens and distinguishing infectious/non-infectious etiologies. This is a retrospective self-controlled study enrolling patients diagnosed with severe pneumonia at the institution between 2024 and 2025 (recruitment will be extended 6-12 months if fewer than 400 patients are enrolled), all of whom underwent both single lung CT and bronchoscopy-combined CT examinations. Clinical data will be collected retrospectively, including demographic information, bronchoscopic mucosal findings (e.g., congestion, exudation), lung CT lesion characteristics (e.g., consolidation, ground-glass opacity), and gold standard diagnostic results (pathogenic detection or clinical comprehensive diagnosis). The core objective is to compare the diagnostic precision between single lung CT and bronchoscopy-combined CT, focusing on accuracy, sensitivity, and specificity across three etiological subtypes (bacterial/fungal, viral, non-infectious). Bronchoscopy complements CT by directly visualizing airway mucosal changes, while CT provides panoramic views of pulmonary lesions. Their combination is hypothesized to improve diagnostic accuracy. The findings aim to optimize diagnostic strategies for severe pneumonia, guiding clinicians to select more effective imaging approaches.

Study Type

OBSERVATIONAL

Enrollment

400

Conditions

Severe Pneumonia

Interventions

Standard chest CT scan (including plain scan and/or enhanced scan as clinically needed) performed to evaluate pulmonary lesion location, scope, and imaging features (e.g., consolidation, ground-glass opacity). The CT findings will be used to preliminarily infer the presence of infectious pathogens and guide initial clinical judgment.

Bronchoscopic Imaging + Lung CT for Severe Pneumonia diagnosisDIAGNOSTIC_TEST

Based on pre-existing lung CT images (to locate lesions), flexible bronchoscopy is performed to directly observe mucosal changes in the tracheobronchial tree (e.g., congestion, edema, exudation). Bronchoscopic imaging features are combined with CT findings to comprehensively judge the type of infectious pathogen (e.g., bacterial vs. viral) and improve diagnostic accuracy.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 80 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients admitted to the study institution between January 2024 and December 2025, with a clinical diagnosis of severe pneumonia (consistent with the diagnostic criteria of the Chinese Guidelines for the Diagnosis and Treatment of Community-Acquired Pneumonia. * Patients who underwent both standalone lung CT examination and bronchoscopic imaging examination during hospitalization; complete imaging reports and bronchoscopy operation records are available. * Patients who completed at least one type of microbial standard test (as defined in Primary Outcome Measure: e.g., pathogen culture, nucleic acid detection, GM test); complete test reports are available. * Medical Records: Complete electronic medical records are available, including demographic information (age, gender), clinical symptoms, treatment regimens, and prognosis data (length of hospital stay, in-hospital mortality). Exclusion Criteria: * Imaging/Microbial Data Deficiency: Patients with incomplete imaging data (e.g., missing lung CT images, unrecorded bronchoscopic mucosal changes) or unavailable microbial gold standard test results. * Bronchoscopy Contraindications: Patients who underwent bronchoscopic imaging for non-diagnostic purposes (e.g., foreign body removal, hemostasis) or had bronchoscopy-related complications (e.g., severe hemorrhage, pneumothorax) that affected examination completion. * Duplicate Enrollment: Patients who were admitted multiple times for severe pneumonia during the study period; only the first admission is included to avoid duplicate data.

Outcomes

Primary Outcomes

Diagnostic Accuracy of Two Imaging Methods for Infectious Pathogens in Severe Pneumonia

For each patient in the cohort, the diagnostic results of standalone lung CT and bronchoscopic imaging + lung CT will be compared with the "standard for pathogen diagnosis" (e.g., pathogen culture, nucleic acid detection, serological testing) to calculate two key indicators: 1. Sensitivity: The proportion of patients with positive gold standard results that are correctly identified as positive by the diagnostic method; \>2. Specificity: The proportion of patients with negative gold standard results that are correctly identified as negative by the diagnostic method. primary goal is to verify whether the combined imaging method (bronchoscopy + CT) has higher sensitivity and specificity than standalone CT for identifying infectious pathogens (including bacteria, fungi, and viruses).

Time frame: Data collection will be completed retrospectively within 6 months after the last patient (admitted by 2025) is included; diagnostic accuracy analysis will be finished within 6 months after data collection.