Acute calculous cholecystitis (ACC) is the most common complication of gallstone disease, and laparoscopic cholecystectomy is the gold standard treatment. Several prospective studies have demonstrated that same-admission, early LC (ELC), for ACC is safe when compared with delayed LC (DLC). However, there is still controversy on the indication of ELC in high risk patients with important comorbidities, in cases of severe inflammation of the gallbladder and in patients with ACC and suspicious of a choledocholithiasis. The advantages of ELC in high risk patients with severe comorbidities have been recently questioned, with Tokyo Guidelines 2018 (TG18) proposing an initial conservative management of this cases, assessing the benefit of ELC according to specified criteria. However, the recent CHOCOLATE trial, demonstrated the advantages of ELC over an initial conservative management. Performing an ELC for ACC can be a straightforward procedure for an on-call general surgeon or a very challenging procedure even for experienced hepatopancreaticobiliary (HPB) laparoscopic surgeon, depending on disease features, surgeons experience, centres volumes and resources available. Deciding whether the ELC should be performed by the on-call team or by HPB surgical team, or whether the operation should be delayed are still matter of debate in daily practice.

Several preoperative scores assessing the risk of difficult cholecystectomy have been proposed, but they were mainly focused on elective procedures and on risk of conversion to open cholecystectomy or other intraoperative complications. They did not asses the risk of post-operative complications in a subgroup of patients, for whom, indication to ELC by the on-call general surgeon is still questionable according to the more recent guidelines.

Inclusion Criteria:

• Patients aged 18 years or older diagnosed with Acute calculous cholecystitis.
• Consecutive patients undergoing early laparoscopic cholecystectomy between January 2013 and December 2018 during admission for the acute episode.
• Minimum 30-day post-operative follow-up.
• ASA ≤ 3.

Exclusion Criteria:

• Presence of another concomitant pathology of the bile duct (choledocholithiasis, cholangitis, pancreatitis, biliary peritonitis).
• Aetiology other than cholelithiasis (amythiasis, malignancy).
• Patients with severe sepsis, immunosuppression and pregnancy.
• Additional abdominal surgical procedure.
• ASA 4.

CLP surgery patients between January 2013 and December 2018. The diagnosis of acute cholecystitis will be established according to the Tokio Guidelines:

• Local signs (pain in right hypochondrium / Murphy's sign).
• Systemic (fever / elevated C-reactive protein / leukocytosis)
• Ultrasound findings (gallbladder distension, wall thickening, pericolectic fluid or radiological Murphy's sign, associated with gallstones). In all patients, treatment with antibiotics will be carried out according to each hospital's protocols in terms of type and duration.