Mirizzi syndrome is a rare cause of obstructive jaundice. First described by Mirizzi in 1948, this syndrome refers to stone impaction in the neck of the gallbladder or the cystic duct, with subsequent inflammation and extrinsic compression of the main bile duct leading to obstructive jaundice and cholangitis (type I Mirizzi syndrome) In more advanced cases, cholecystocholedochal fistulas can be seen (type II Mirizzi syndrome) and there can also be cholecystoduodenal, cholecystocolonic, and cholecystogastric fistulas[i],[ii],[iii],[iv][v]. Mirizzi syndrome is often not recognized preoperatively, which can lead to significant morbidity and biliary injury, particularly with laparoscopic surgery[vi].

This rare gallstone disease complication is seen 0,1% to 0,7% of the patients with gallstones. Mirizzi syndrome is also associated with a higher risk of gallbladder cancer (more than 25% in this group of patients)[vii], and sometimes it is difficult to exclude concomitant neoplasic disease of the gallbladder.

The most common clinical presentation includes jaundice, fever, and right upper quadrant pain[viii], in association with elevated alkaline phosphatase and bilirrubin serum level in more than 90 percent of patients.

As in every obstructive jaundice diagnostic approach, the ultrasonography (US) is in the Mirizzi syndrome frequently a first-line diagnostic examination, as it is the procedure of choice for the initial evaluation of cholestasis and for helping differentiate extrahepatic from intrahepatic causes of jaundice.

• The US in the Mirizzi syndrome can show (1) dilatation of the biliary system above the level of the gallbladder neck, (2) a stone impacted in the gallbladder neck and (3) narrowing of the CHD at the level of impaction and an abrupt change to a normal width of the common duct below the level of the stone[ix],[x].
• The magnetic resonance cholangiopancreatography (MRCP) is the following diagnostic study and can show (1) an impacted stone in the gallbladder neck (2) compression of the common hepatic duct (3) dilatation of the biliary system above the level of impaction and (4) a contracted gallbladder with wall-thickening[xi]. Additional sequences should be used to exclude the presence of malignancy.
• Computed tomography (CT) scanning does not significantly add to sonographic findings with respect to the stone and biliary obstruction.
• Finally, the endoscopic retrograde cholangiopancreatography (ERCP) is probably the criterion standard. Typical findings are (1) dilatation of the biliary system (2) visible calculus in the expected position of the cystic duct (3) smooth, lateral, and extrinsically compressed common hepatic duct and (4) gallbladder exclusion[xii]. ERCP also can be used to temporarily relieve stenosis by means of stent placement.
• Percutaneous transhepatic cholangiography (PTC) may also be used for diagnosis, if ERCP fails[xiii].

Surgery is the mainstay of therapy of Mirizzi syndrome. If the diagnosis of Mirizzi syndrome is made preoperatively, an operative strategy that minimizes the risk of injury to the biliary tract can be carried out.

The surgical approach depends on the variant of the Mirizzi syndrome, and it includes cholecystectomy plus common bile duct exploration with T-tube placement, fistula suture with absorbable material or choledochoplasty with the remnant gallbladder, and bilioenteric anastomosis when the entire wall of the common bile duct has been destroyed[xiv]. The operative mortality and postoperative morbidity increase according to the severity of the lesion.

There is still controversy about the use of laparoscopic surgery for Mirizzi syndrome because of the anatomical distortion, so it has been suggested to perform a laparoscopic dissection trial and convert to an open procedure if local conditions are not clear[xv].

Endoscopic management can also be attempted to decompress the bile duct or gallbladder, but usually as a temporizing measure before surgery or as a definitive treatment for unsuitable surgical candidates[xvi].