Overview
Definition
An acute infection of the pulmonary parenchyma acquired outside of the hospital setting.
Epidemiology
One of the most common infectious causes of death. Higher risk in elderly and immunocompromised.
Etiology & Risk Factors
- Streptococcus pneumoniae (most common typical)
- Mycoplasma pneumoniae (atypical)
- Haemophilus influenzae
- Respiratory viruses (Influenza, RSV, SARS-CoV-2)
Clinical Symptoms
- Productive cough
- Fever/Chills
- Pleuritic chest pain
- Dyspnea
- Fatigue
Clinical Approach
Diagnosis
- Chest X-ray (demonstrating an infiltrate/consolidation)
- Sputum gram stain and culture
- Urine antigen tests (Legionella, S. pneumo)
Management
- Outpatient: Amoxicillin OR Doxycycline OR Macrolide
- Inpatient (Non-severe): Ceftriaxone + Azithromycin OR Respiratory Fluoroquinolone
- Inpatient (Severe): Ceftriaxone + Azithromycin + consider MRSA/Pseudomonas coverage
Complications
- Parapneumonic effusion / Empyema
- Sepsis
- ARDS
- Lung abscess