What is the initial treatment for community-acquired pneumonia (CAP)?

From the Guidelines

The initial treatment for community-acquired pneumonia (CAP) should be guided by the most recent and highest quality evidence, which recommends empiric antibiotic therapy based on the patient's clinical presentation, age, and risk factors, with a minimum treatment duration of 5 days, as suggested by the 2021 study 1.

Key Considerations

• For outpatient treatment of previously healthy adults, a macrolide antibiotic such as azithromycin or doxycycline is recommended, as stated in the 2003 study 1.
• For patients with comorbidities or recent antibiotic use, a respiratory fluoroquinolone like levofloxacin or a combination of amoxicillin-clavulanate plus a macrolide is preferred, as suggested by the 2019 study 1.
• Hospitalized non-ICU patients typically receive a beta-lactam plus a macrolide, while ICU patients may require broader coverage with a beta-lactam plus either a macrolide or fluoroquinolone, as recommended by the 2019 study 1.

Treatment Duration

• The treatment duration should be guided by validated measures of clinical stability, which include resolution of vital sign abnormalities, ability to eat, and normal mentation, as stated in the 2021 study 1.
• The minimum treatment duration is 5 days, but extension of therapy after 5 days should be based on clinical stability, as suggested by the 2021 study 1.

Antibiotic Choice

• The antibiotic choice should target the most common CAP pathogens, including Streptococcus pneumoniae, Haemophilus influenzae, and atypical organisms like Mycoplasma pneumoniae, as stated in the 2003 study 1.
• The choice of antibiotic should be based on effective treatment of the most commonly reported bacterial pathogens and may include an aminopenicillin with clavulanic acid, a macrolide, or a tetracycline, as suggested by the 2021 study 1.

From the FDA Drug Label

1. 2 Community-Acquired Pneumonia: 7 to 14 day Treatment Regimen Levofloxacin tablets are indicated in adult patients for the treatment of community-acquired pneumonia due to methicillin-susceptible Staphylococcus aureus, Streptococcus pneumoniae (including multi-drug-resistant Streptococcus pneumoniae [MDRSP]), Haemophilus influenzae, Haemophilus parainfluenzae, Klebsiella pneumoniae, Moraxella catarrhalis, Chlamydophila pneumoniae, Legionella pneumophila, or Mycoplasma pneumoniae

2. 3 Community-Acquired Pneumonia: 5-day Treatment Regimen Levofloxacin tablets are indicated in adult patients for the treatment of community-acquired pneumonia due to Streptococcus pneumoniae (excluding multi-drug-resistant isolates [MDRSP]), Haemophilus influenzae, Haemophilus parainfluenzae, Mycoplasma pneumoniae, or Chlamydophila pneumoniae

The initial treatment for community-acquired pneumonia (CAP) with levofloxacin tablets is a 7 to 14 day treatment regimen for certain pathogens, or a 5-day treatment regimen for other specific pathogens 2.

• The 7 to 14 day regimen is used to treat CAP due to:
  • Methicillin-susceptible Staphylococcus aureus
  • Streptococcus pneumoniae (including multi-drug-resistant Streptococcus pneumoniae [MDRSP])
  • Haemophilus influenzae
  • Haemophilus parainfluenzae
  • Klebsiella pneumoniae
  • Moraxella catarrhalis
  • Chlamydophila pneumoniae
  • Legionella pneumophila
  • Mycoplasma pneumoniae
• The 5-day regimen is used to treat CAP due to:
  • Streptococcus pneumoniae (excluding multi-drug-resistant isolates [MDRSP])
  • Haemophilus influenzae
  • Haemophilus parainfluenzae
  • Mycoplasma pneumoniae
  • Chlamydophila pneumoniae

From the Research

Initial Treatment for Community-Acquired Pneumonia (CAP)

The initial treatment for community-acquired pneumonia (CAP) typically involves empiric antibiotic therapy, with the choice of antibiotics depending on various factors such as the severity of the disease, patient's age, and presence of comorbidities.

• The most commonly used antibiotics for CAP include levofloxacin, ceftriaxone, imipenem-cilastatin, and azithromycin 3.
• A study found that azithromycin-containing regimens were associated with the lowest rates of nonresponsiveness 4.
• Another study compared the efficacy and tolerability of ceftriaxone plus azithromycin with those of levofloxacin in hospitalized patients with moderate to severe CAP, and found that both treatments were well tolerated and had similar clinical outcomes 5.
• Guidelines-concordant empiric antimicrobial therapy has been shown to be associated with lower mortality in patients with severe CAP requiring mechanical ventilation 6.

Antibiotic Choices

The choice of antibiotics for CAP depends on various factors, including the severity of the disease and the presence of comorbidities.

• Ceftriaxone is recommended as first-line antibiotic treatment for hospitalized adults with CAP, with the addition of a macrolide 7.
• Ampicillin may be associated with comparable clinical outcomes to ceftriaxone, with less emergence of resistant pathogens or Clostridioides difficile infection (CDI) 7.
• Levofloxacin is a commonly used antibiotic for CAP, but its use has been associated with higher rates of CDI 7.
• Azithromycin is often used in combination with other antibiotics, such as ceftriaxone, for the treatment of CAP 5.

Treatment Outcomes

The treatment outcomes for CAP depend on various factors, including the severity of the disease, patient's age, and presence of comorbidities.

• A study found that guidelines-concordant empiric antimicrobial therapy was associated with lower 7-day mortality in patients with severe CAP requiring mechanical ventilation 6.
• Another study found that azithromycin-containing regimens were associated with the lowest rates of nonresponsiveness 4.
• The clinical outcomes of patients with CAP treated with ceftriaxone plus azithromycin or levofloxacin were similar, with favorable clinical outcomes in 91.5% and 89.3% of patients, respectively 5.