R — Renal (Blood Urea Nitrogen / Urea Level)

BUN ≤ 14 mg/dL OR urea ≤ 5 mmol/L (normal)+0BUN > 14 mg/dL OR urea > 5 mmol/L (elevated)+1

A — Age

< 50 years+050–70 years+1> 70 years+2

P — Purulence of Pleural Fluid

Non-purulent (turbid, clear, or bloody but not frank pus)+0Purulent (frank pus aspirated from the pleural space)+1

I — Infection Source

Community-acquired pneumonia (onset in community setting)+0Hospital-acquired (empyema onset > 48h after admission, post-surgical, or post-procedural)+1

D — Dietary (Serum Albumin Level)

Serum albumin ≥ 27 g/L (≥ 2.7 g/dL) — adequate nutrition+0Serum albumin < 27 g/L (< 2.7 g/dL) — hypoalbuminemia+1

RAPID Score for Pleural Infection

RAPID Score for Pleural Infection