Community-Acquired Pneumonia Diagnosis and Treatment

Diagnostic Criteria

The presence of a consolidation area at the left base with suspicion of a second lingular focus constitutes clear radiographic evidence of pneumonia, even in a patient initially presenting with cold symptoms, according to the American College of Chest Physicians 1, 2
The presence of cough with dyspnea or pleuritic pain is a symptom to be evaluated for pneumonia diagnosis, as recommended by the American College of Chest Physicians 1, 3
Fever ≥38°C, chills, and sweats are clinical signs to be assessed for pneumonia, as suggested by the American College of Chest Physicians 1, 4
Tachypnea (respiratory rate >24/min) is a sign that accompanies pneumonia, according to the American College of Chest Physicians 1, 5
The absence of nasal discharge (absence of rhinorrhea) significantly increases the probability of pneumonia, as noted by the American College of Chest Physicians 1, 6

A C-reactive protein (CRP) level >30 mg/L in the presence of suggestive symptoms and signs strongly increases the probability of pneumonia, as recommended by the American College of Chest Physicians 1, 6
A CRP level <10 mg/L or between 10-50 mg/L in the absence of dyspnea and daily fever makes pneumonia less likely, according to the American College of Chest Physicians 6, 5
Measuring CRP strengthens both the diagnosis and exclusion of pneumonia, as suggested by the American College of Chest Physicians 1, 3

Empiric antibiotic treatment according to local and national guidelines is recommended for outpatients with radiographic evidence of pneumonia, as recommended by the American College of Chest Physicians 1, 3
If antiviral treatment is indicated, initiating it within 48 hours of symptom onset can decrease antibiotic use and hospitalization, as noted by the American College of Chest Physicians 1, 7