What is the best course of treatment for a patient with influenza who is currently taking prednisone (a corticosteroid) for an underlying condition?

Management of Influenza in Patients Taking Prednisone

Primary Recommendation

Do not initiate or add corticosteroids for the treatment of influenza itself, but continue existing prednisone therapy at the lowest effective dose to prevent adrenal insufficiency while treating the influenza infection aggressively with antivirals. 1, 2

Critical Evidence Against Adding Corticosteroids for Influenza

The evidence strongly demonstrates harm from corticosteroid use in influenza:

• Meta-analyses of 19 studies (6,637 patients) show corticosteroid therapy significantly increases mortality (OR 1.98,95% CI 1.62-2.43) and nosocomial infections (OR 3.16,95% CI 2.09-4.78) in influenza patients. 3
• The Infectious Diseases Society of America explicitly recommends against administering corticosteroids for seasonal influenza, influenza-associated pneumonia, respiratory failure, or ARDS (A-III recommendation). 1
• Corticosteroids prolong mechanical ventilation duration by 3.82 days and ICU stay by 4.78 days in influenza patients. 3
• Meta-analysis of Asian cohorts demonstrated corticosteroid therapy was associated with superinfection and increased mortality in seasonal and pandemic influenza. 4

Management of Existing Prednisone Therapy

For patients already on prednisone who develop influenza:

• Continue the prednisone but reduce to the lowest dose possible to control the underlying condition and avoid adrenal insufficiency. 1, 2
• Never abruptly discontinue corticosteroids in patients taking >5 mg/day of prednisone or equivalent due to risk of acute adrenal insufficiency. 1, 5
• Patients on chronic systemic steroids are at higher risk for influenza complications and require close monitoring. 2

Recommended Treatment Algorithm for Influenza

Immediate Antiviral Therapy

• Initiate oseltamivir 75 mg orally twice daily for 5 days as soon as possible, regardless of time since symptom onset in severe cases. 1, 2
• Dose reduction to 75 mg once daily is required if creatinine clearance is <30 mL/min. 2
• Treatment benefits are greatest within 48 hours of symptom onset, but hospitalized patients with severe illness benefit even when started beyond 48 hours. 2

Antibiotic Coverage for Bacterial Coinfection

• All patients with influenza pneumonia should receive empiric antibiotics to cover bacterial coinfection or secondary infection. 2
• Target pathogens include S. pneumoniae, H. influenzae, M. catarrhalis, and Staphylococcus aureus. 2
• For non-severe pneumonia: oral co-amoxiclav or tetracycline. 2
• For severe pneumonia: intravenous broad-spectrum β-lactamase stable antibiotic plus a macrolide. 2

Monitoring and Supportive Care

• Investigate bacterial coinfection in patients who deteriorate after initial improvement or fail to improve after 3-5 days of antiviral treatment. 1
• Monitor closely for development of secondary infections, as corticosteroids increase this risk (OR 3.15,95% CI 1.54-6.45). 6

Vaccination Considerations

Influenza Vaccination While on Prednisone

• Administer inactivated influenza vaccine regardless of prednisone dose—do not defer vaccination even at doses ≥20 mg daily. 7
• Use only inactivated (killed) influenza vaccine, never live attenuated vaccine in patients on any dose of oral steroids. 7
• Timely influenza protection outweighs concerns about potentially reduced antibody response at high steroid doses. 7

Antibody Response Considerations

• High-dose steroids (≥20 mg prednisone daily) may blunt vaccine immunogenicity, but vaccination should still proceed without delay for influenza. 7
• Consider measuring pathogen-specific antibody concentrations after vaccination in patients on high-dose glucocorticoids (≥2 mg/kg or ≥20 mg/day for ≥2 weeks). 4, 7

Common Pitfalls to Avoid

• Do not add corticosteroids thinking they will reduce inflammation in influenza pneumonia—this consistently worsens outcomes. 1, 2, 3
• Do not abruptly stop chronic prednisone therapy in patients who develop influenza, as this risks life-threatening adrenal crisis. 1, 5
• Do not defer influenza vaccination while waiting for steroid taper—vaccinate immediately regardless of dose. 7
• Do not use live attenuated influenza vaccine in any patient on immunosuppressive steroid therapy. 7

Special Circumstances

Patients with Life-Threatening Underlying Conditions

• In cases of rheumatic disease with severe manifestations threatening life or organs, the benefits of maintaining corticosteroids may outweigh risks, even with influenza present. 1
• This requires careful individualized assessment balancing the severity of the underlying condition against influenza-related risks. 1

Adrenal Suppression Risk

• Patients on prednisone >5 mg/day or equivalent are at risk for HPA axis suppression. 5
• During influenza illness (a physiologic stressor), patients with suppressed HPA axis may require stress-dose corticosteroids if they become critically ill, despite the general recommendation against corticosteroids for influenza. 5
• This represents continuation of necessary replacement therapy, not treatment of influenza itself. 1