What corticoid (corticosteroid) dose is a risk factor for pseudomonal infection?

Corticosteroid Dose as a Risk Factor for Pseudomonal Infection

A corticosteroid dose equivalent to ≥20 mg of prednisolone for ≥2 weeks is associated with an increased risk of opportunistic infections, including those caused by Pseudomonas aeruginosa. 1

Risk Factors Related to Corticosteroid Use

• Corticosteroids at a total daily dose equivalent to ≥20 mg of prednisolone for ≥2 weeks significantly increase the risk of opportunistic infections, including pseudomonal infections 1
• In the CORRONA registry, even doses ≥10 mg/day of prednisolone increased the relative risk for all infectious events (RR 1.30), while any dose increased the risk of opportunistic infections (RR 1.67) 1
• The use of corticosteroids is an independent risk factor for nosocomial infections caused by Pseudomonas aeruginosa (OR=3.143,95% CI 1.115-8.856) 2
• The immunosuppressive effect of corticosteroids is dose-dependent, with higher doses associated with greater risk 1

Specific Thresholds and Risk Stratification

• High-dose corticosteroids are defined as:
  • ≥20 mg/day of prednisolone for ≥2 weeks 1
  • ≥2 mg/kg or a total dose of ≥20 mg/day for ≥2 weeks 1
• Patients receiving prolonged corticosteroid therapy at these doses should be considered at high risk for opportunistic infections 1
• Combination of corticosteroids with other immunomodulators substantially increases the risk (up to 14-fold with multiple immunomodulators) 1

Additional Risk Factors That Potentiate Corticosteroid Risk

• Mechanical ventilation significantly increases the risk of pseudomonal infection in patients on corticosteroids (OR=3.195,95% CI 1.607-6.353) 2
• Advanced age is an independent risk factor that compounds the risk of opportunistic infections in patients on corticosteroids 1
• Prior exposure to carbapenems within 90 days is a risk factor for carbapenem-non-susceptible Pseudomonas aeruginosa infections 3
• Malnutrition further increases the risk of opportunistic infections in patients on corticosteroids 1

Preventive Strategies

• For patients requiring ≥20 mg/day of prednisolone for ≥2 weeks, consider:
  • Monitoring for early signs of infection 1
  • Prophylactic antimicrobials in high-risk patients 4
  • Minimizing steroid dose whenever possible 1
• In perioperative settings, minimize corticosteroid use to reduce the risk of postoperative infectious complications 1
• For patients with inflammatory bowel disease on high-dose steroids, combination with other immunomodulators should be carefully evaluated due to the multiplicative risk 1

Common Pitfalls and Caveats

• Short-term high-dose corticosteroid treatment (<2 weeks) carries less risk than prolonged therapy 5
• Preventive measures are typically not required for patients receiving <15 mg/day of prednisolone or short courses (≤7 days) of higher doses 5
• The risk of infection persists even after discontinuation of corticosteroids, particularly in the first few months 3
• Monitoring lymphocyte counts is important, as decreased peripheral blood lymphocyte counts (<500/μL) at 2 weeks after starting corticosteroids is an independent risk factor for opportunistic infections 4
• Patients with respiratory disease who are on corticosteroids are at particularly high risk for pseudomonal infections 3

Remember that the risk of pseudomonal and other opportunistic infections increases not only with the dose and duration of corticosteroid therapy but also with the concurrent use of other immunomodulators, patient age, and comorbidities 1.