Cephalosporins for Community-Acquired Pneumonia
For community-acquired pneumonia (CAP), the recommended cephalosporins are ceftriaxone and cefotaxime, which are considered parenteral drugs of choice for CAP caused by susceptible strains of Streptococcus pneumoniae. 1
First-Line Cephalosporin Options
- Ceftriaxone and cefotaxime are the preferred cephalosporins for CAP, active in vitro against 90-95% of S. pneumoniae, Haemophilus influenzae, and methicillin-susceptible Staphylococcus aureus 1
- Standard dosing for ceftriaxone is 1-2 g IV every 24 hours for 5-7 days in patients who become afebrile within 48 hours, or 10-14 days for more severe cases or those with bacteremia 2
- Ceftriaxone is effective against pneumococcal strains with penicillin MICs ≤2 mg/L 2
Newer Cephalosporin Options
- Ceftaroline is a fifth-generation cephalosporin FDA-approved for CABP in adults and pediatric patients 2 months of age and older 3
- In clinical trials, ceftaroline (600 mg IV every 12 hours) was non-inferior to ceftriaxone (1-2 g IV every 24 hours) for treatment of CAP 3, 4
- Ceftaroline demonstrates potent activity against multi-drug resistant S. pneumoniae and methicillin-resistant S. aureus, offering an advantage for resistant pathogens 5
- Ceftobiprole is another fifth-generation cephalosporin with extended spectrum activity, but it is not approved for use in pneumonia in the US 1
Oral Cephalosporin Options
- Oral cephalosporins like cefadroxil (500 mg twice daily) and cephalexin (250 mg four times daily) have shown efficacy in mild to moderate CAP in outpatient settings 6
- Sequential therapy switching from IV ceftriaxone to oral ceftibuten has demonstrated similar efficacy to continued IV therapy in patients showing clinical improvement 7
Combination Therapy Considerations
- Cephalosporins alone are not active against atypical pathogens (Mycoplasma, Chlamydophila, Legionella), so combination therapy is often recommended 2
- A retrospective analysis of 14,000 Medicare patients showed higher mortality for cephalosporins alone compared to cephalosporins plus macrolides or fluoroquinolones alone 1
- When treating CAP in hospitalized patients, the recommended approach is an extended-spectrum cephalosporin (cefotaxime or ceftriaxone) plus a macrolide 1
- For severe CAP with suspected drug-resistant S. pneumoniae, ceftriaxone may be combined with a macrolide or respiratory fluoroquinolone 2
Common Pitfalls and Caveats
- Cephalosporins as monotherapy are not effective against atypical pathogens, which may lead to treatment failure if these organisms are present 2
- Increasing resistance by S. pneumoniae to cephalosporins is a concern, necessitating susceptibility testing in areas with high prevalence of drug-resistant S. pneumoniae 2
- Once-daily dosing of ceftriaxone allows for outpatient treatment of severe bacterial pneumonias in clinically stable patients, potentially reducing hospitalization days 8
- In patients showing clinical improvement after initial IV therapy, an early switch to oral therapy can safely reduce hospital stay and treatment costs 7