Community-Acquired Pneumonia: Treatment

Author and Disclosure Information



Antibiotic Therapy for Selected Pathogens

Streptococcus pneumoniae

Patients with pneumococcal pneumonia who have penicillin-susceptible strains can be treated with intravenous penicillin (2 or 3 million units every 4 hours) or ceftriaxone. Once a patient meets criteria of stability, they can then be transitioned to oral penicillin, amoxicillin, or clarithromycin. Those with strains with reduced susceptibility can still be treated with penicillin, but at a higher dose (4 million units intravenously [IV] every 4 hours), or a third-generation cephalosporin. Those whose pneumococcal pneumonia is complicated by bacteremia will benefit from dual therapy if severely ill, requiring ICU monitoring. Those not severely ill can be treated with monotherapy.20

Staphylococcus aureus

Staphylococcus aureus is more commonly associated with hospital-acquired pneumonia, but it may also be seen during the influenza season and in those with severe necrotizing CAP. Both linezolid and vancomycin can be used to treat MRSA CAP. As noted, ceftaroline has activity against MRSA and is approved for treatment of CAP, but is not approved by the FDA for MRSA CAP treatment. Similarly, tigecycline is approved for CAP and has activity against MRSA, but is not approved for MRSA CAP. Moreover, the FDA has warned of increased risk of death with tigecycline and has a black box warning to that effect.21


Legionellosis can be treated with tetra¬cyclines, macrolides, or fluoroquinolones. For non-immunocompromised patients with mild pneumonia, any of the listed antibiotics is considered appropriate. However, patients with severe infection or those with immunosuppression should be treated with either levofloxacin or azithromycin for 7 to 10 days.22

Chlamydophila pneumoniae

As with other atypical organisms, Chlamydophila pneumoniae can be treated with doxycycline, a macrolide, or respiratory fluoroquinolones. However, length of therapy varies by regimen used; treating with doxycycline 100 mg twice daily generally requires 14 to 21 days, whereas moxifloxacin 400 mg daily requires 10 days.23

Mycoplasma pneumoniae

As with C. pneumoniae, length of therapy of Mycoplasma pneumoniae varies by which antimicrobial regimen is used. Shortest courses are seen with the use of macrolides for 5 days, whereas 14 days is considered standard for doxycycline or a respiratory fluoroquinolone.24 It should be noted that there has been increasingly documented resistance to macrolides, with known resistance of 8.2% in the United States.25


Next Article: