What are the best treatment options for community-acquired pneumonia (CAP) in both pediatric and adult patients?

Management of Community-Acquired Pneumonia in Pediatric and Adult Patients

For pediatric CAP, amoxicillin 90 mg/kg/day divided into three doses for 5 days is first-line therapy in fully immunized children, while adults hospitalized with bacterial CAP should receive β-lactam/macrolide combination therapy such as ceftriaxone plus azithromycin for a minimum of 3 days. 1, 2, 3

Pediatric CAP Management

Initial Assessment and Site of Care Decision

Pulse oximetry is mandatory for all children with suspected pneumonia to identify hypoxemia, which directly determines whether outpatient or inpatient management is appropriate. 1, 4

• Outpatient management is appropriate for well-appearing, fully immunized children without hypoxemia or respiratory distress 4
• Hospitalization is required for infants <3-6 months, children with moderate-to-severe respiratory distress, hypoxemia (SpO2 <90%), or those requiring supplemental oxygen 1, 4
• ICU admission criteria include need for mechanical ventilation, non-invasive positive pressure ventilation, fluid-refractory shock, or FiO2 requirements exceeding what general care can provide 1, 4

Diagnostic Approach in Children

Chest radiographs are NOT routinely necessary for outpatient CAP diagnosis in children well enough for ambulatory management. 1, 4 This represents a critical practice point to avoid unnecessary radiation exposure and healthcare costs.

• Obtain chest X-rays only for hospitalized patients, those with hypoxemia, significant respiratory distress, or failed initial antibiotic therapy 1, 4
• Blood cultures should NOT be routinely obtained in non-toxic, fully immunized outpatient children 4
• Blood cultures ARE indicated for all hospitalized children with presumed bacterial CAP, particularly those with complicated pneumonia 4

Antibiotic Selection for Pediatric CAP

The choice of antibiotic depends critically on immunization status and age:

For Fully Immunized Children (Against H. influenzae type b and S. pneumoniae):

• Amoxicillin 90 mg/kg/day divided into 3 doses for 5 days is first-line therapy 1, 3
• Two daily doses may be considered to improve compliance, though three doses is preferred 3
• Antimicrobial therapy is NOT routinely required for preschool-aged children, as viral pathogens cause the majority of cases in this age group 4

For Incompletely Immunized Children:

• Amoxicillin-clavulanate OR second/third-generation cephalosporins should be used instead of amoxicillin alone 3
• This broader coverage accounts for potential H. influenzae type b infection 3

For Children >5 Years with Persistent Symptoms:

• Add macrolides to amoxicillin if symptoms persist after 48 hours but clinical condition remains stable 3
• This targets atypical pathogens like Mycoplasma pneumoniae which become more common in school-age children 3

Monitoring and Follow-up in Children

Clinical reassessment at 48-72 hours after starting antibiotics is essential to identify treatment failure early. 4, 3

• Repeat chest radiographs are NOT needed in children recovering uneventfully 1, 4
• Obtain follow-up imaging only for clinical deterioration, lack of improvement at 48-72 hours, or suspected complications 1, 4
• Acute-phase reactants (CRP, ESR, procalcitonin) should not be used alone to distinguish viral from bacterial CAP, but may help assess treatment response in hospitalized patients 1, 4

Adult CAP Management

Antibiotic Selection for Hospitalized Adults

For hospitalized adults without risk factors for resistant bacteria, β-lactam/macrolide combination therapy is the standard of care. 2

• Ceftriaxone plus azithromycin for minimum 3 days represents the most commonly used regimen 2
• This combination provides coverage for S. pneumoniae (the most common identified bacterial pathogen, found in ~15% of cases with identified etiology) and atypical organisms 2
• Only 38% of hospitalized CAP patients have a pathogen identified; of those with identified pathogens, up to 40% have viral etiologies 2

Testing and Pathogen-Specific Considerations

All patients with CAP must be tested for COVID-19 and influenza when these viruses are circulating in the community, as positive results alter treatment (antiviral therapy) and infection prevention strategies. 2

• If viral testing is negative or these pathogens are unlikely, proceed with empirical antibacterial therapy 2
• Consider disease severity and likelihood of bacterial infection versus risk of antibiotic overuse when selecting therapy 2

Severe CAP in Adults

Systemic corticosteroids administered within 24 hours of severe CAP development may reduce 28-day mortality. 2 This represents an important adjunctive therapy beyond antibiotics alone.

Long-term Outcomes

Guideline-concordant antibiotic therapy is associated with nearly 50% reduction in cardiovascular death risk at 1 year post-CAP in older adults (HR 0.53,95% CI 0.34-0.80). 5 This finding emphasizes the importance of following evidence-based recommendations, as benefits extend far beyond the acute infection period.

Management of Complicated CAP

Parapneumonic Effusions

Effusion size and respiratory compromise determine management strategy:

Small Effusions (<10mm rim):

• Antibiotics alone without drainage 1, 6
• Do not obtain pleural fluid for culture 1
• Reassess effusion size regularly 1

Moderate Effusions (≥10mm but <50% thorax):

• Low respiratory compromise: IV antibiotics alone with close monitoring 1, 6
• High respiratory compromise: Obtain pleural fluid for culture via thoracentesis or chest tube placement 1, 6

Large Effusions (≥50% thorax):

• Chest tube with fibrinolytics is preferred for loculated effusions, associated with decreased morbidity compared to chest tube alone 1, 6
• For free-flowing effusions without loculations, chest tube alone is reasonable first option 1
• VATS should be performed if moderate-to-large effusions persist with ongoing respiratory compromise despite 2-3 days of chest tube management and fibrinolytic therapy 1

Antibiotic Duration for Complicated CAP

Parapneumonic effusions require 2-4 weeks of total antibiotic therapy, substantially longer than uncomplicated pneumonia. 1, 6

• Duration depends on adequacy of drainage and clinical response 1, 6
• When cultures identify a pathogen, antibiotic susceptibility must guide therapy 1, 6
• For culture-negative effusions, follow the same antibiotic recommendations as hospitalized CAP patients 1, 6

Treatment Failure

Children not responding after 48-72 hours require systematic reassessment:

• Clinical and laboratory assessment to determine if higher level of care is needed 1
• Imaging evaluation to assess pneumonia progression 1
• Further microbiologic investigation for persistent pathogens, antibiotic resistance, or secondary infections 1
• BAL should be obtained in mechanically ventilated children 1, 7
• Percutaneous lung aspirate should be considered in persistently ill children without microbiologic diagnosis 1

Critical Pitfalls to Avoid

• Do not overuse antibiotics in preschool-aged children where viral etiologies predominate 4
• Do not obtain routine chest X-rays for outpatient CAP diagnosis in well-appearing children 1, 4
• Do not perform routine daily chest radiography in children with parapneumonic effusions after chest tube placement if clinically stable 1, 4
• Do not miss hypoxemia assessment with pulse oximetry, as this is the critical determinant for hospitalization 1, 4
• Do not use acute-phase reactants alone to distinguish viral from bacterial CAP 1