What is the management of community-acquired pneumonia (CAP)?

From the Guidelines

Community-acquired pneumonia (CAP) should be managed with empiric antibiotic therapy, with the choice of antibiotics based on the severity of the disease and the patient's underlying health status, as recommended by the American Thoracic Society and Infectious Diseases Society of America guideline from 2019 1. For outpatient treatment of mild to moderate CAP in adults:

• First-line therapy: Amoxicillin 1 g orally three times daily for 5-7 days.
• For patients with penicillin allergy or in areas with high pneumococcal resistance:
  • Doxycycline 100 mg orally twice daily for 5-7 days, or
  • Azithromycin 500 mg orally on day 1, then 250 mg daily for 4 days
• For patients with comorbidities or recent antibiotic use:
  • Amoxicillin-clavulanate 875/125 mg orally twice daily for 5-7 days, plus
  • Azithromycin 500 mg orally on day 1, then 250 mg daily for 4 days Supportive care is crucial and includes:

• Rest
• Adequate hydration
• Antipyretics for fever (e.g., acetaminophen)
• Follow-up within 48-72 hours to assess response For severe CAP requiring hospitalization:
• Intravenous antibiotics (e.g., ceftriaxone plus azithromycin)
• Oxygen therapy as needed
• Close monitoring of vital signs and oxygenation The choice of antibiotics targets the most common causative organisms (Streptococcus pneumoniae, Haemophilus influenzae, and atypical pathogens like Mycoplasma pneumoniae), as outlined in the guideline 1. The management of CAP should prioritize the patient's quality of life, morbidity, and mortality, with a focus on timely and effective antibiotic therapy, as well as supportive care to reduce the risk of complications and improve outcomes 1.

From the FDA Drug Label

Azithromycin for Injection, USP is indicated for the treatment of patients with infections caused by susceptible strains of the designated microorganisms in the conditions listed below... Community-acquired pneumonia due to Chlamydia pneumoniae, Haemophilus influenzae, Legionella pneumophila, Moraxella catarrhalis, Mycoplasma pneumoniae, Staphylococcus aureus, or Streptococcus pneumoniae in patients who require initial intravenous therapy Azithromycin should not be used in patients with pneumonia who are judged to be inappropriate for oral therapy because of moderate to severe illness or risk factors such as any of the following: patients with cystic fibrosis, patients with nosocomially acquired infections, patients with known or suspected bacteremia, patients requiring hospitalization, elderly or debilitated patients, or patients with significant underlying health problems that may compromise their ability to respond to their illness (including immunodeficiency or functional asplenia) The recommended dose of azithromycin for oral suspension for the treatment of pediatric patients with community-acquired pneumonia is 10 mg/kg as a single dose on the first day followed by 5 mg/kg on Days 2 through 5

The management of community-acquired pneumonia (CAP) with azithromycin involves:

• Initial IV therapy: Azithromycin for Injection, USP is indicated for the treatment of CAP due to susceptible strains of designated microorganisms in patients who require initial intravenous therapy.
• Oral therapy: Azithromycin can be used for oral therapy in patients with mild severity CAP, but should not be used in patients with moderate to severe illness or certain risk factors.
• Pediatric dosing: The recommended dose of azithromycin for oral suspension for the treatment of pediatric patients with CAP is 10 mg/kg as a single dose on the first day followed by 5 mg/kg on Days 2 through 5 2.
• Adult dosing: The recommended dose of azithromycin for adults with CAP is 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5 2. It is essential to note that azithromycin should only be used to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria, and that culture and susceptibility tests should be performed before treatment to determine the causative microorganism and its susceptibility to azithromycin 3.

From the Research

Management of Community-Acquired Pneumonia (CAP)

The management of CAP involves several key components, including:

• Assessment of disease severity to determine the site of care (outpatient, inpatient, or intensive care) 4, 5, 6, 7, 8
• Administration of appropriate antibiotic therapy tailored to the likely offending pathogens and the severity of disease 4, 6, 7, 8
• Use of empiric therapy regimens, such as macrolides, beta-lactams, and respiratory fluoroquinolones, based on the severity of disease and the prevalence of resistance 4, 5, 6, 7, 8
• Consideration of local resistance patterns when choosing empiric therapy 8

Antibiotic Therapy

The choice of antibiotic therapy for CAP depends on several factors, including:

• Disease severity: more severe disease requires broader-spectrum antibiotics 4, 6, 7, 8
• Likely offending pathogens: Streptococcus pneumoniae is the most common causative pathogen, but other pathogens such as Haemophilus influenzae, Legionella pneumophila, and Mycoplasma pneumoniae may also be present 5, 6, 8
• Prevalence of resistance: local resistance patterns must be considered when choosing empiric therapy 8

Site of Care

The site of care for CAP patients depends on the severity of disease, with:

• Outpatient management for mild disease 4, 6, 7
• Inpatient management for moderate to severe disease 4, 5, 6, 7, 8
• Intensive care unit (ICU) admission for severe disease or patients with risk factors for methicillin-resistant Staphylococcus aureus or Pseudomonas 5, 8

Other Considerations

Other considerations in the management of CAP include:

• Use of prediction rules, such as the PORT Severity Index, CURB-65, or CRB-65, to determine the need for hospitalization 5, 8
• Collection of blood cultures and other diagnostic tests to guide antibiotic therapy 5
• Consideration of adjunctive therapies, such as corticosteroids, in severe CAP 7