ERS/ESICM/ESCMID/ALAT 2023: severe community-acquired pneumonia guidelines

Who it applies to

Adults with severe community-acquired pneumonia managed in ICU or high-dependency settings, excluding hospital-acquired and ventilator-associated pneumonia.

Key recommendations

• Use validated severity criteria (such as ATS/IDSA minor criteria or validated severity scores) alongside clinical judgement to identify patients needing ICU-level care, rather than relying on a single score in isolation.
• Obtain blood cultures, respiratory sampling (sputum or lower respiratory tract samples, including bronchoscopic sampling where feasible and safe), and urinary antigen testing for pneumococcus and Legionella before starting antibiotics whenever this does not delay therapy.
• Use multiplex molecular/PCR panels on respiratory samples where available to improve detection of bacterial and viral pathogens and support antibiotic streamlining.
• Start empirical combination therapy with a broad-spectrum beta-lactam plus a macrolide as the preferred initial coverage for severe CAP without specific resistance risk factors, with a beta-lactam plus a respiratory fluoroquinolone as an alternative option.
• Assess for risk factors for Pseudomonas aeruginosa and extend-spectrum resistant organisms (prior isolation, structural lung disease, recent broad-spectrum antibiotics, local epidemiology) to guide broader empirical coverage.
• Assess for risk factors for methicillin-resistant Staphylococcus aureus (prior MRSA colonization, recent influenza-like illness, necrotizing pneumonia features) to decide on empirical anti-MRSA coverage.
• Consider adjunctive systemic corticosteroids in selected patients with severe CAP, recognizing a mortality or clinical improvement benefit shown in trial data, while weighing risks such as hyperglycemia and secondary infection.
• De-escalate and shorten antibiotic therapy once a pathogen is identified and the patient is clinically improving, guided by clinical response and biomarkers such as procalcitonin, rather than a fixed long course.
• Test for influenza and initiate antiviral therapy promptly when influenza is suspected or confirmed in severe CAP, as delayed treatment reduces benefit.
• Do not use antibiotics alone to manage suspected viral severe CAP (including COVID-19 associated pneumonia) and instead apply disease-specific supportive and antiviral/immunomodulatory strategies where indicated.

What is new in this edition

• Greater emphasis on routine use of multiplex molecular diagnostics to guide and narrow empirical therapy
• More structured, risk-factor-based approach to deciding on empirical anti-pseudomonal and anti-MRSA coverage rather than blanket broad-spectrum therapy
• Expanded guidance incorporating lessons from the COVID-19 pandemic on viral severe CAP management

Practice points for students

• Severity assessment should combine validated criteria with clinical gestalt; no single score replaces bedside judgement in deciding ICU admission.
• Always attempt pathogen identification before antibiotics when feasible, since this underpins safe de-escalation later.
• Empirical dual therapy for severe CAP without resistance risk factors favors a beta-lactam plus macrolide, with a beta-lactam plus fluoroquinolone as an alternative.
• Corticosteroids are not for routine use in all severe CAP but are considered in selected patients based on trial evidence of benefit.
• Rapid influenza testing matters because antiviral benefit is highly time-dependent.

Condition

Other guidelines on this topic

• Diagnosis and Management of Community-acquired Pneumonia: An Official American Thoracic Society Clinical Practice GuidelineATS2026Official guideline
• Pneumonia (community-acquired): antimicrobial prescribing (NG138)NICE2019Summary

Independent educational summary written by the WhiteCoat Pro editorial team with AI assistance and checked by a second AI model. It does not reproduce the guideline text, tables or figures, and it is not affiliated with or endorsed by ERS. It is not medical advice: always read the original guideline before applying it to patients.