- Age ≥ 18- The diagnoses acute calculous cholecystitis defined according to the Tokyo Guidelines:A. Local signs of inflammation: (1) Murphy's sign, (2) Right upper quadrant mass/pain/tendernessB. Systemic signs of inflammation: (1) Fever, (2) elevated CRP, (3) elevated WBC countC. Imaging findings: imaging findings characteristic of acute cholecystitisDefinite diagnosis:(1) One item in A and one item in B are positive(2) C confirms the diagnosis when acute cholecystitis is suspected clinically- APACHE-II score ≥ 7 AND ≤ 14- Written informed consent. This evidence concerns the gene CRP and Cholecystitis, Acute.