Community-Acquired Pneumonia Visualized on CT Scans but Not Chest Radiographs: Pathogens, Severity, and Clinical...

Area of Science:

• Pulmonary Medicine
• Radiology
• Infectious Diseases

Background:

• The clinical significance of pneumonia detected solely by CT scan, with a normal chest radiograph, remains unclear.
• Community-acquired pneumonia (CAP) management guidelines often rely on chest radiograph findings.

Purpose of the Study:

• To compare clinical features, pathogens, and outcomes of CAP patients with CT-only pneumonia versus those with radiograph-confirmed pneumonia.

Main Methods:

• A multicenter prospective surveillance study involving 2,251 adults hospitalized with CAP.
• Patients underwent chest radiography; CT scans were obtained at clinician discretion.
• Radiologists blinded to clinical data interpreted all imaging.

Main Results:

• 3% of patients (66/2251) had CT-only pneumonia; their clinical profiles were similar to the 97% with radiograph-confirmed pneumonia.
• No significant differences observed in comorbidities, vital signs, length of stay, pathogen prevalence, ICU admission, mechanical ventilation, septic shock, or in-hospital mortality.
• Specific pathogen prevalence: viral (30% vs 26%), bacterial (12% vs 14%) for CT-only vs radiograph groups, respectively.

Conclusions:

• Adults with CT-only pneumonia exhibit similar disease severity and outcomes compared to those with pneumonia visible on chest radiography.
• Findings support applying consistent management principles for both CT-only pneumonia and radiograph-detected pneumonia.