Synopsis
Diagnose pneumonia clinically and radiographically where appropriate, use CRB65/CURB65 plus judgement to select care, and give severity-matched antibiotics, oxygen and adjunctive treatment with explicit review points.
- CAP is an acute lower respiratory infection acquired outside hospital with compatible clinical features and, in hospital, usually new radiographic shadowing not explained by another cause.
- Assess ABCDE, SpO2, sepsis physiology, ability to take oral medicines, frailty/comorbidity and social support before scoring severity.
- CRB65 in the community and CURB65 in hospital support risk assessment: Confusion, urea above 7 mmol/L, respiratory rate at least 30/min, low BP, age 65 or over; each scores 1.
- Scores supplement judgement. Profound hypoxaemia, shock, multilobar disease, immunosuppression or rapid deterioration can indicate high severity despite a low number.
- Low-severity adult CAP: amoxicillin 500 mg orally three times daily for 5 days; doxycycline 200 mg day 1 then 100 mg daily or clarithromycin 500 mg twice daily are alternatives when appropriate.
- Moderate severity: amoxicillin 500 mg TDS for 5 days, adding clarithromycin 500 mg BD if atypical pathogens are suspected; doxycycline or clarithromycin alone can be alternatives in penicillin allergy.
- High severity: co-amoxiclav 500/125 mg orally TDS or 1.2 g IV TDS plus clarithromycin 500 mg BD (oral/IV as appropriate), review route and total duration at 5 days.