| Grade | Criteria | Management |
|---|---|---|
| Grade I (Mild) | Meets local/systemic signs; no Grade II or III criteria | Early LC; can be elective same admission |
| Grade II (Moderate) | Local/systemic signs + ≥1: WBC >18, RUQ mass, >72h, severe local imaging | Early LC preferred within 72h; cholecystostomy if not safe |
| Grade III (Severe) | Any organ dysfunction | Emergency drainage, ICU, reassess for LC after stabilisation |
TG18 updated from TG13; the grade determines the urgency and type of intervention for acute cholecystitis.