Mirizzi syndrome

Excerpt

An 80-year-old gentleman presented to the emergency room for worsening jaundice. He had a history of cholelithiasis and end-stage COPD. Laboratory evaluation was notable for a total bilirubin 18.5 mg/dL (range 0.2–1.3 mg/dL), direct bilirubin 16.7 mg/dL (normal < 0.3), indirect bilirubin 1.8 mg/dL, AST 69 U/L (normal 17–59), ALT 51 U/L (normal < 50), alkaline phosphatase 294 U/L (normal < 127) and gamma glutamyl transferase 637 U/L (range 15–73). A contrast-enhanced computed tomography (CT) of the abdomen showed markedly dilated biliary ducts and a large calcified stone in the distended gallbladder (Fig. 1A). Further evaluation with magnetic resonance cholangiopancreatography (MRCP) revealed the large gallstone distending the gallbladder neck and causing extensive mass effect upon the common hepatic and bile duct. There was marked dilatation of the intrahepatic bile ducts upstream from this obstruction, extending down to the common hepatic duct bifurcation in the porta hepatis (Fig. 1B). A diagnosis of Mirizzi syndrome was made. MRCP provides greater diagnostic accuracy for Mirizzi syndrome compared to CT due to its ability to demonstrate biliary calculi as small as 2 mm, external compression or dilatation of the common hepatic duct, strictures and delineate anatomy of the biliary ducts [1, 2] providing a road map for planning endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic cholangiography. Mirizzi syndrome occurs secondary to multiple impacted gallstones or a single large impacted gallstone in Hartman's pouch of the gallbladder or in the cystic duct causing external compression of the common hepatic duct [3]. In some instances, Mirizzi syndrome accrues from acute or chronic inflammation secondary to gallstone(s) in the cystic duct and Hartmann’s pouch or infundibulum of the gallbladder. Chronic inflammation of the gallbladder can predispose it to form adhesions to the surrounding structures, most commonly the hepatic duct. This process leads to progressive narrowing of the hepatic duct, not only due to the inflammatory stricture but also from the extrinsic compression of the gallstone [3, 4]. Eventually the mucosal lining may erode leading to the formation a fistula. Obstructive jaundice is the most common feature (50–100%) along with right upper quadrant (50–100%) or epigastric pain, dark urine (62.5%), fever and chills. It is important to bear in mind that these symptoms are not unique to Mirrizi syndrome and can be the presenting complaint of pancreatitis, acute cholecystitis and choledocholithiasis [4]. Surgery is the treatment of choice; however, an ERCP is often recommended prior to define the anatomy of the biliary tree, assess for the presence of fistula and even relieve biliary obstruction via stent placement which can potentially improve surgical outcome [4]. An ERCP was performed which again showed compression of the bile duct by the gallstone (Fig. 1C) and a stent was placed in the biliary duct. The procedure is generally palliative and a bridge to surgery. Unfortunately, he had a significant decline in his respiratory status over the next few days and he opted to pursue hospice care.

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