When to use corticosteroids in community-acquired pneumonia (CAP)?

When to Use Corticosteroids in Community-Acquired Pneumonia

Use corticosteroids in hospitalized patients with severe CAP who have high inflammatory markers (CRP >150 mg/L) or septic shock requiring vasopressors, but avoid them entirely in influenza pneumonia. 1, 2

Primary Indications for Corticosteroid Use

Severe CAP with high inflammatory response is the clearest indication for corticosteroid therapy. The Society of Critical Care Medicine and European Society of Intensive Care Medicine recommend corticosteroids for 5-7 days at doses <400 mg IV hydrocortisone equivalent in hospitalized CAP patients, with the strongest benefits seen in severe disease. 3

Specific Clinical Scenarios Where Corticosteroids Should Be Used:

• Septic shock refractory to fluid resuscitation requiring vasopressors - This represents the highest-yield population for corticosteroid benefit, particularly when combined with elevated CRP >150 mg/L. 3, 1

• CRP >150-204 mg/L at admission - The most recent 2025 data-driven analysis of randomized trials demonstrates that patients with CRP >204 mg/L show substantial mortality reduction (13.0% vs 6.1%, OR 0.43), while those with CRP ≤204 mg/L show no benefit (OR 0.98). 4 Earlier studies used a threshold of >150 mg/L with demonstrated treatment failure reduction. 5, 1

• Major severity criteria present - Patients requiring invasive mechanical ventilation and/or with septic shock show 18% vs 31% mortality with corticosteroids (HR 0.53, p=0.043), while those without major criteria show no benefit (HR 0.88). 6

Dosing Regimens

Methylprednisolone 0.5 mg/kg IV every 12 hours for 5 days is the most evidence-based regimen for severe CAP. 3, 1 For patients able to take oral medications, prednisone 50 mg daily is adequate. 3

The optimal dose appears to be approximately 6 mg of dexamethasone equivalent for 7 days duration, based on dose-response meta-analysis showing non-linear relationship with mortality (RR 0.44). 7 Daily doses should remain <400 mg hydrocortisone equivalent. 3, 1

Absolute Contraindications

Influenza pneumonia (including H1N1) represents an absolute contraindication to corticosteroids regardless of severity or shock state. 3, 2 Meta-analyses demonstrate increased mortality with corticosteroid use in influenza patients. 3, 2 The IDSA/ATS explicitly recommend against corticosteroid use in influenza with a conditional recommendation. 2

Even in the presence of refractory septic shock from H1N1 pneumonia, corticosteroids should be avoided due to prolonged viral shedding, delayed clearance, and increased mortality risk. 2

Clinical Benefits in Appropriate Patients

When used in severe CAP with high inflammatory response, corticosteroids provide:

• Mortality reduction - Overall 30-day mortality decreases from 9.06% to 6.15% (RR 0.67), with more pronounced effects in severe pneumonia (OR 0.26 in severe CAP subgroup). 8, 3

• Prevention of mechanical ventilation - Reduces need for invasive mechanical ventilation by more than half (RR 0.45). 3, 8

• ARDS prevention - Decreases ARDS development substantially (RR 0.24). 3

• Reduced ICU admission - Probably reduces ICU admission risk (RR 0.65). 7

• Shortened hospital stay - Reduces length of stay by approximately 1 day. 3, 7

Important Caveats and Monitoring

Hyperglycemia is the most common adverse effect, occurring with increased frequency (RR 1.49-2.50). 3, 8, 4 Monitor glucose closely and treat aggressively during corticosteroid therapy. 1

Hospital readmission risk increases (3.7% vs 7.0%, OR 1.95), requiring careful discharge planning and follow-up. 4

Neuromuscular weakness may occur, particularly in sicker patients, though this is likely underestimated in trials. 3

Duration beyond 7 days is unnecessary and increases adverse effects without additional benefit. 1

When NOT to Use Corticosteroids

The IDSA/ATS 2019 guideline provides a strong conditional recommendation against routine use of adjunctive steroids in general CAP patients. 3 This applies to:

• Mild-to-moderate CAP without major severity criteria (no mortality benefit, RR 1.08). 7

• Low inflammatory markers (CRP ≤150-204 mg/L) where no treatment effect is demonstrated. 4, 5

• Any viral pneumonia, particularly influenza, where harm outweighs any potential benefit. 3, 2

• Patients not requiring vasopressors or mechanical ventilation and without elevated inflammatory markers. 6

Practical Algorithm

1. Confirm bacterial (not viral) CAP - Obtain respiratory cultures and viral testing, particularly for influenza. 2

2. Assess severity - Determine if patient meets major criteria (invasive mechanical ventilation and/or septic shock). 6

3. Check CRP - If CRP >150-204 mg/L AND severe CAP present, initiate corticosteroids. 4, 5, 1

4. Exclude influenza - If influenza positive, do NOT use corticosteroids regardless of severity. 2

5. Use appropriate dosing - Methylprednisolone 0.5 mg/kg IV q12h or prednisone 50 mg daily for 5-7 days only. 1, 3

6. Monitor complications - Check glucose regularly and watch for secondary infections. 1