Table 1.

Diagnostic criteria and severity classification of acute cholecystitis of TG18/TG13. Modified from Yokoe et al. [19].

DIAGNOSIS Suspicion: one criterion A + one criterion B Definitive diagnosis: one criterion A + one criterion B + one criterion C	A. Local inflammation A-1 Murphy’s sign A-2 Pain/mass/tenderness in upper right quadrant	B. Systemic inflammation B-1 Fever B-2 Elevated CPR B-3 Elevated leukocyte count	C. Image C-1 Characteristic findings of acute cholecystitis
SEVERITY	SEVERE (grade III)	MODERATE (grade II)	MILD (grade I)
	It is associated with dysfunction in one of the following organs/systems 1. Cardiovascular: hypotension requiring dopamine > 5 µg/kg/min, or any dose of norepinephrine 2. Neurological: decrease in the level of consciousness 3. Respiratory: PaO2/FiO2 ratio <300 4. Renal: oliguria, creatinine > 2.0 mg/dL 5. Liver: PT-INR > 1.5 6. Haematological: platelet count < 100,000 mm3	It is associated with one of the following: 1. Leukocytosis (>18,000/mm3) 2. Palpable mass with tenderness in upper right quadrant 3. Duration of symptoms > 72 h 4. Marked local inflammation (gangrenous cholecystitis, pericholecystic abscess, liver abscess, biliary peritonitis, emphysematous cholecystitis)	Does not meet criteria for severe or moderate cholecystitis. It can be defined as acute cholecystitis in a healthy patient without organic dysfunction and with mild inflammatory changes in the gallbladder