PIRO Score for Community-Acquired Pneumonia

PIRO Score Calculator

Age > 70 years

COPD

Immunocompromised

Multilobar CXR infiltrates

Bacteremia

Systolic BP < 90 mmHg

Severe sepsis

ARDS

Acute Kidney Injury

Other organ failure

PIRO Score: 0

Low Risk

PIRO Score: 0. Low mortality risk from community-acquired pneumonia.

Predicts ICU mortality in patients with community-acquired pneumonia.

Why Use

Consists of easily accessible variables known to impact CAP mortality. Unlike similar tools, PIRO is specifically tailored for severe CAP cases requiring ICU admission. Predicts 28-day mortality and ICU resource utilization. Identifies high-risk patients who may need closer monitoring and more aggressive management. Facilitates risk stratification for clinical research on novel or targeted therapies. Outperformed APACHE II and the 2007 ATS/IDSA CAP severity/management criteria in predicting mortality in the derivation study.

When to Use

Use within 24 hours of a community-acquired pneumonia (CAP) diagnosis in adults (≥18 years) to assess disease severity and predict mortality.

Formula

Addition of the selected points: Variable Points Predisposition Comorbitities (COPD or immunocompromised) Yes 1 No 0 Age >70 years Yes 1 No 0 Insult Bacteremia Yes 1 No 0 Multilobar opacities in chest radiograph Yes 1 No 0 Response Shock Yes 1 No 0 Severe hypoxemia Yes 1 No 0 Organ dysfunction Acute renal failure Yes 1 No 0 Acute respiratory distress syndrome Yes 1 No 0

Pearls / Pitfalls

Developed using data from 529 patients with severe CAP admitted to ICUs across 33 hospitals in Spain. Variability in ICU admission criteria for CAP may lead to differences in mortality rates between institutions. Although designed for ICU patients, the score has been validated in general ward and emergency department settings; however, its predictive accuracy remains strongest for critically-ill patients. Does not incorporate biomarker data (e.g., procalcitonin), which may also aid in risk assessment.

Advice

No specific management guidelines are linked to PIRO score results. Higher scores correlate with increased mortality, prolonged ICU stay, and extended mechanical ventilation. Results may inform prognosis discussions and guide decisions on treatment setting (e.g., ICU, stepdown, medical ward), aggressive interventions, and adjunctive therapies (e.g., corticosteroids).

More Information

Interpretation: PIRO Score for CAP Risk Level 28-day Mortality 0-2 Low 3.6% 3 Mild 13.0% 4 High 43.0% 5-8 Very high 76.3%