Respiratory Emergency Medicine General Medicine Strong — validated in >50,000 patients

Pneumonia Severity Index (PSI/PORT)

Predicts 30-day mortality in community-acquired pneumonia. Simplified from the full Fine/PORT score.

Score interpretation

Class I–II (Low Risk) -99–50

PSI Class I–II (age ≤50 + no comorbidities, or score ≤70): 30-day mortality 0.1–0.7%. Note: Class I is assigned clinically (age ≤50, no comorbidities).

→ Outpatient treatment appropriate for most patients.

Class III (Low-Moderate Risk) 51–90

PSI Class III (score 51–90): 30-day mortality ~2.8%. Low-moderate risk.

→ Brief inpatient observation or outpatient treatment. Clinical judgement required.

Class IV (Moderate Risk) 91–130

PSI Class IV (score 91–130): 30-day mortality ~8.2%. Moderate risk.

→ Inpatient treatment recommended.

Class V (High Risk) ≥ 131

PSI Class V (score > 130): 30-day mortality ~29.2%. High risk.

→ Inpatient treatment. Consider ICU if sepsis criteria met or deteriorating.

Interpretation bands for the PSI/PORT. Apply clinical judgement and local guidance.

References

Fine MJ et al. A prediction rule to identify low-risk patients with community-acquired pneumonia. N Engl J Med. 1997.

Curated clinical cross-links plus same-class fallbacks.

Calculators

Drugs

Pathways

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.

Score interpretation

References

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