Community Acquired Pneumonia (CAP)
Definition
Pneumonitis - non infective, just inflammation
Pneumonia - infective
Epidemiology
Mortality 20% (if admitted to ICU: 40-50%)
Common Aetiology
Clinical Features
Symptoms
NOTE: Typical bact can cause atypical sx, vice versa
Signs
Investigations
NOTE: S. pneumonia/ H. influzena (smokers) may be cultured but may not be the cause
Management
Complications
Source
Dr Gregory Haug 2014
Pneumonitis - non infective, just inflammation
Pneumonia - infective
Epidemiology
Mortality 20% (if admitted to ICU: 40-50%)
Common Aetiology
- Bacteria (Strep pneumonia, GN - common in nursing homes)
- Atypical bacteria (Legionella pneumoniae, mycoplasma pneumonia, chlamydia pneumonia, norcadia, TB)
- Viral (Influenza A*, swine flu (H1N1) - fat youngsters no herd immunity since epidemic, adenovirus, RSV, H. Zoster-pregnant females immunocompromised)
- Fungal (cryptococcus)
Clinical Features
Symptoms
- Fever/ rigors/ headache
- Productive cough/ rusty sputum
- Chest pain
- If atypical, abdo pain, paucity of resp sx
NOTE: Typical bact can cause atypical sx, vice versa
Signs
- RR** (most important indicator of severity)
- Febrile (>39/ <36)/ tachypnoeic/ tachycardic, hypotensive
- Confusion (elderly)
- Consolidation (dull percussion/ diminished expansion, tactile fremitus/ vocal resonant/ bronchial breath sounds)
- Pleural rub
Investigations
- Bedside: Sputum (routine/ lavage culture), nasopharyngeal swab (virus), Legionella urinary antigen (only 1 serotype, useful in epidemics)
- Bloods: Blood culture (30% pneumoncoccal --> S. pneumonia bacteremia), atypical serology (ab to atypicals), UEC (electrolyte imbalance), ABG (resp function)
- Imaging: CXR (consolidation)
NOTE: S. pneumonia/ H. influzena (smokers) may be cultured but may not be the cause
Management
- Severity: CURB-65 C: confusion U: uraemia R: RR>30 B: SBP<90, 65: age. 1 point for each. 0-1, d/c, 2 - admit, 3-5 - consider ICU
- Empirical abx
- Mild: Macrolide/ doxycycline
- Moderate: B lactam/ macrolide
- Severe: IV B lactam/ macrolide
Complications
- Ventilatory failure
- Death
- Pleural effusion (sx: ++dyspnoea, 2nd spike in fever, pleuritic pain. Rx: Tap immediately)
Source
Dr Gregory Haug 2014