CURB-65 pneumonia severity calculator
Score community-acquired pneumonia and decide home, ward or ICU.
What CURB-65 is for
CURB-65 estimates the 30-day risk of death in community-acquired pneumonia and helps decide where to treat the patient: at home, on the ward or in HDU/ICU. NICE and the British Thoracic Society use it alongside clinical judgement.
The criteria (one point each)
- Confusion: new disorientation in person, place or time.
- Urea above 7 mmol/L. Most Pakistani labs report urea in mg/dL: 7 mmol/L is about 42 mg/dL. If your lab reports BUN instead, the cut-off is about 20 mg/dL.
- Respiratory rate 30 or more per minute.
- Blood pressure: systolic below 90 mmHg or diastolic 60 mmHg or less.
- Age 65 or over.
Interpreting the score
- 0–1: low risk. Consider home treatment with oral antibiotics if oxygen saturation is normal and there is someone at home.
- 2: intermediate risk. Consider admission or short-stay observation.
- 3–5: high risk. Admit, treat as severe pneumonia and discuss HDU/ICU, especially at 4 or 5.
Worked example
A 70-year-old man, alert, respiratory rate 32, BP 110/70, urea 50 mg/dL. Points for age, urea and respiratory rate: CURB-65 = 3, so admit as severe pneumonia, send blood cultures and start IV antibiotics as per your local guideline.
Limitations and pitfalls
- It does not include oxygen saturation. A young patient with SpO₂ of 88% can score 0 and still need admission and oxygen.
- It was not designed for hospital-acquired pneumonia, aspiration, immunosuppression or tuberculosis.
- Look for alternatives that mimic pneumonia in Pakistan: tuberculosis, pulmonary oedema, and fever with chest signs from dengue or typhoid.
- Score at presentation and reassess if the patient deteriorates; NEWS2 is better for tracking.
See community-acquired pneumonia, cough and chest infection in OPD, low oxygen saturations, sepsis and the drug pages for amoxicillin, co-amoxiclav and clarithromycin.
Frequently asked questions
What is the CRB-65 score?
CURB-65 without urea, scored 0–4, used in clinics and general practice where blood tests are not available. A score of 0 is low risk; 1 or more suggests hospital assessment.
What urea value counts in CURB-65 in mg/dL?
Urea above 7 mmol/L, which is about 42 mg/dL of urea. If your lab reports blood urea nitrogen (BUN), use about 20 mg/dL.
Can a patient with CURB-65 of 0 need admission?
Yes. Low oxygen saturation, inability to take oral medicines, frailty, pregnancy, poor social support or a sick-looking patient all justify admission whatever the score.
Is CURB-65 used for hospital-acquired pneumonia?
No. It was developed for community-acquired pneumonia and should not be used to judge severity in hospital-acquired or aspiration pneumonia.
A calculator supports, but does not replace, clinical judgement. Check results before acting on them.