From the Guidelines
Community-acquired pneumonia (CAP) should be treated with antibiotics based on the severity of the disease and the patient's underlying health conditions, with a focus on covering Streptococcus pneumoniae, Haemophilus influenzae, and atypical pathogens. The diagnostic criteria for CAP include symptoms such as cough, fever, and shortness of breath, along with radiographic evidence of lung infiltration.
Treatment Options
For outpatient treatment of mild to moderate CAP in otherwise healthy adults, azithromycin 500mg on day 1 followed by 250mg daily for 4 more days is recommended as first-line therapy 1. Alternatives include doxycycline 100mg twice daily or amoxicillin 1g three times daily for 5 days, particularly if atypical pathogens are suspected.
- For patients with comorbidities or risk factors, amoxicillin-clavulanate 875/125mg twice daily plus azithromycin is appropriate 1.
- Severe CAP requires hospitalization with intravenous antibiotics, typically a respiratory fluoroquinolone like levofloxacin 750mg daily or a combination of ceftriaxone 1-2g daily plus azithromycin 1.
Supportive Care
Supportive care includes adequate hydration, fever control, and oxygen supplementation if needed. Patients should see improvement within 48-72 hours of starting antibiotics.
Pathophysiology and Risk Factors
The pathophysiology involves microorganisms reaching the lower respiratory tract and overwhelming host defenses, with Streptococcus pneumoniae being the most common bacterial cause 1. Risk factors include advanced age, smoking, chronic diseases, and immunosuppression.
Prevention Strategies
Prevention strategies include pneumococcal and influenza vaccinations, smoking cessation, and good hand hygiene.
- The selection of initial empiric therapy for CAP should be based on the patient's severity of illness, comorbidities, and recent antibiotic use, as outlined in the guidelines 1.
From the FDA Drug Label
14.2 Community-Acquired Pneumonia: 7 to 14 Day Treatment Regimen
Adult inpatients and outpatients with a diagnosis of community-acquired bacterial pneumonia were evaluated in 2 pivotal clinical studies
14.3 Community-Acquired Pneumonia: 5 Day Treatment Regimen
To evaluate the safety and efficacy of the higher dose and shorter course of levofloxacin, 528 outpatient and hospitalized adults with clinically and radiologically determined mild to severe community-acquired pneumonia were evaluated in a double-blind, randomized, prospective, multicenter study comparing levofloxacin 750 mg, IV or orally, every day for five days or levofloxacin 500 mg IV or orally, every day for 10 days.
The diagnostic criteria for Community-Acquired Pneumonia (CAP) are not explicitly stated in the provided drug label. However, the treatment options for CAP include:
- Levofloxacin 500 mg once daily orally or intravenously for 7 to 14 days
- Levofloxacin 750 mg once daily orally or intravenously for 5 days The clinical success rates for these treatment options are:
- 95% for levofloxacin 500 mg at 5 to 7 days posttherapy
- 93% for levofloxacin 500 mg in a non-comparative trial
- 90.9% for levofloxacin 750 mg for 5 days
- 91.1% for levofloxacin 500 mg for 10 days 2
From the Research
Diagnostic Criteria for Community-Acquired Pneumonia (CAP)
- Diagnosis is suggested by a history of cough, dyspnea, pleuritic pain, or acute functional or cognitive decline, with abnormal vital signs (e.g., fever, tachycardia) and lung examination findings 3
- Diagnosis should be confirmed by chest radiography or ultrasonography 3
- Validated prediction scores for pneumonia severity can guide the decision between outpatient and inpatient therapy 3
- Using procalcitonin as a biomarker for severe infection may further assist with risk stratification 3
Treatment Options for CAP
- Most outpatients with community-acquired pneumonia do not require microbiologic testing of sputum or blood and can be treated empirically with a macrolide, doxycycline, or a respiratory fluoroquinolone 3
- Patients requiring hospitalization should be treated with a fluoroquinolone or a combination of beta-lactam plus macrolide antibiotics 3, 4
- Patients with severe infection requiring admission to the intensive care unit require dual antibiotic therapy including a third-generation cephalosporin plus a macrolide alone or in combination with a fluoroquinolone 3
- Treatment options for patients with risk factors for Pseudomonas species include administration of an antipseudomonal antibiotic and an aminoglycoside, plus azithromycin or a fluoroquinolone 3
- Patients with risk factors for methicillin-resistant Staphylococcus aureus should be given vancomycin or linezolid, or ceftaroline in resistant cases 3
- Administration of corticosteroids within 36 hours of hospital admission for patients with severe community-acquired pneumonia decreases the risk of adult respiratory distress syndrome and length of treatment 3
Prevention of CAP
- The 23-valent pneumococcal polysaccharide and 13-valent pneumococcal conjugate vaccinations are both recommended for adults 65 years and older to decrease the risk of invasive pneumococcal disease, including pneumonia 3