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CURB-65 Calculator — CAP Severity Score

Severity assessment for adult community-acquired pneumonia with 30-day mortality bands and recommended disposition. Calculations run locally in your browser.

C — Confusion

New-onset disorientation to person, place or time, OR Abbreviated Mental Test (AMT) ≤ 8.

U — Urea

Criterion met if urea > 7 mmol/L (or BUN > 19 mg/dL).

Enter a value to auto-set this criterion.

R — Respiratory rate

Criterion met if respiratory rate ≥ 30 breaths/min.

breaths/min

Enter a value to auto-set this criterion.

B — Blood pressure

Criterion met if SBP < 90 mmHg OR DBP ≤ 60 mmHg.

/ mmHg

Enter SBP and DBP to auto-set this criterion.

65 — Age

Criterion met if age ≥ 65 years.

years

Enter age to auto-set this criterion.

CURB-65 Score

Disclaimer: This calculator is for clinical decision support only and is not a substitute for clinical judgment. Always integrate with the patient's full clinical picture, comorbidities, social context, and local guidelines (e.g., ICMR, IDSA/ATS, BTS). CURB-65 supports — but does not replace — bedside assessment, oxygenation status (SpO₂/ABG), and a structured ICU-admission decision (e.g., IDSA/ATS minor + major criteria).

References

  1. Lim WS, van der Eerden MM, Laing R, et al. Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study. Thorax 2003;58(5):377–382.
  2. Lim WS, Baudouin SV, George RC, et al. British Thoracic Society guidelines for the management of community acquired pneumonia in adults: update 2009. Thorax 2009;64(Suppl III):iii1–iii55.
  3. Metlay JP, Waterer GW, Long AC, et al. Diagnosis and Treatment of Adults with Community-acquired Pneumonia. An Official Clinical Practice Guideline of the American Thoracic Society and Infectious Diseases Society of America. Am J Respir Crit Care Med 2019;200(7):e45–e67.

Mortality estimates are from the original Lim 2003 derivation cohort. Disposition suggestions follow BTS 2009 and IDSA/ATS 2019; defer to your hospital CAP pathway where it differs.

Document CAP severity scores directly in your patient chart with the Dr. Notes app — works offline, keeps records secure.

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